SK117698A3 - Process for scavenging thiols - Google Patents

Abstract

Thiols are trapped, and converted to disulfide compounds, by a process of reacting them with compounds containing a 1,2,4-thiadiazole ring structure carrying a substituent at position 3 of the thiadiazole ring, and being unsubstituted at position N-2. The process is useful pharmacologically, in inhibiting certain thiol-containing enzymes such as H+/K+-ATPase (the proton pump), and industrially, in selective removal of thiol compounds from gas or liquid mixtures.

Description

A process for converting a thiol group to a disulfide group in thiol-containing compounds

Area, techniques

The present invention relates to chemical methods for the uptake of thiols and the selective conversion of thiol compounds to disulfide compounds. Furthermore, it also relates to the use of some thiadiazole compounds, some of which are novel, as thiol scavenging agents ** in a selective reaction with thiols, thus converting them to disulfides.

³ · *.

BACKGROUND OF THE INVENTION

Thiol compounds exist in many chemical and biological systems, and in many cases are undesirable or harmful compounds that require selective removal or chemical transfer from the system. The thiol group SH (otherwise known as the mercaptan group or the hydrogen sulfide group) often causes the compounds containing it to smell unpleasant. Minerals such as mineral fuel deposits (for example, diesel, natural gas and coal) are often contaminated with stinking thiol compounds. Gas eluates from crude oil extraction and refining, coal gasification and natural gas mining are often contaminated with thiols. Thiols need to be removed from them to comply with environmental standards.

The manufacture of certain pharmaceutical products, such as cimetidine, ranitidine, and nizatidine, involves the use of sulfur-containing reagents which provide methyl mercaptan as by-products. The usual way of handling these products is ashing, which leads to the production of sulfuric acid, which is a component of acid rain. An improved method for trapping thiols is also needed in this context.

Thiol scavengers can be used in diagnostic procedures to capture organic mercaptans. They can also be used as diagnostic reagents, for example in the detection of mercaptan groups of proteins.

Particularly important in the context of the present invention is the uptake of biochemical thiol compounds such as enzymes. Many enzymes contain active thiol groups derived from their cysteine residues. Thus, selective inhibition of the activity of these enzymes, reversible or irreversible, by a reaction that modifies their thiol groups in biological systems may therefore form the basis of therapeutic treatment. Examples of these enzymes are cathepsin B, papain, H * / K * -ATPase, interleukin / 3-1 converting enzyme, and protein disulfide isomerase (HIV).

Cathepsin Ba L is associated with many diseases, including progressive cartilage and bone degradation associated with arthritis. Inhibitors of these cathepsins cause a reduction in inflammation and joint destruction in animal models of arthritis. Calcium-related proteases I and II are related to Alzheimer's disease.

Interleukin converting enzyme [M. Mullican et al. »Bioorganic and Medicinal Chem. Lett. 1994, 2359.) is a key target for drug discovery due to its key role in the release of the inflammatory protein interleukin-1 beta. Excessive levels of interleukin-1 beta are involved in a variety of diseases, including rheumatoid arthritis, psoriasis, inflammatory bowel diseases, and insulin-dependent diabetes. Similarly, in a thiol protease, the mechanism of action involves cysteine residues at the active site.

Suggested reversible inhibitors of these enzymes include peptide aldehydes, nitriles and ketocarbonyl compounds. Suggested irreversible inhibitors include peptide halomethyl ketones, diazomethyl ketones, acyloxymethyl ketones, ketomethylsulfonium salts, epoxides, and vinyl sulfones. All of these compounds are known as thiol protease inhibitors. It was not found that any of these structural types had use as a drug candidate.

The enzyme gastric H ^s * / K * -ATPase, also known as a proton pump, is associated with the development of peptic ulcers in mammals. This enzyme also contains active thiol groups derived from their cysteine residues. Inhibition of this enzyme is one of the primary grounds for treating peptic ulcer in humans. Thiol scavengers can be used to inhibit the enzyme H * / K * -ATPase. An example of such a compound is omeprazole.

SUMMARY OF THE INVENTION

The present invention relates to a novel process for the uptake of thiol compounds, characterized in that it is reacted with certain thiadiazoles. Some thiadiazoles used in the present invention are novel chemical compounds. Others are known compounds or have not been previously proposed for this use. These compounds used in the present invention are characterized by the structure of the 1,2,4-thiadiazole ring substituted at the 3-position but unsubstituted at the N-2 position.

One group of compounds for use in the process of the invention are the 1,2,4-thiadiazolo [4,5-a] benzimidazoles of the following Formula I

or a pharmaceutically acceptable salt thereof, wherein R ¹ , R ² , R ³ and R ⁴ independently represent a hydrogen atom, a lower alkyl group, a halogen atom, a nitro group, a hydroxyl group, a lower alkoxy group, a lower alkylamino group, a di (lower alkyl) amino group or a group of the formula NR'R '', OC (O) R ', OC (O) OR', OC (O) NR'R '', NR '(COR'), NHC (O) NR'R ', NHC (O) OR 'or CONR'R ¹¹ , wherein R' and R '' are independently selected from hydrogen, lower alkyl, aryl or lower arylalkyl, or R 'and R''inNR'R ¹¹ form a 5- or 6-membered heterocyclic ring of formula (CH ₂ ) _n wherein n is 4 or 5, and Y is selected from:

(1) groups of the formula wherein R ^-7 is hydrogen, hydroxyl, lower alkyl, lower cycloalkyl, lower alkoxy, lower alkenyl, lower alkynyl, aryl, lower arylalkyl, heterocyclic, heterocyclooxy , heterocyclo- (lower) alkylene, NR'R '', wherein R 'and R''are independently selected from hydrogen, lower alkyl, aryl and lower arylalkyl, or R' and R '' together with the atom nitrogen consists of a 5- or 6-membered heterocyclic ring N (CH) in which n is 4 or 5, and a group ANR'R '' and AOR 'in which A represents an amino acid group or a peptide of 2 to 3 amino acid groups and R' and R ' (2) a heterocyclic group, a lower alkylene-heterocyclic group, a (lower alkyl) - (lower alkylene) heterocyclic amino group, a lower alkylene-amino-heterocyclic group or aminoheterocyclic group, the heterocyclic ring is attached to any heteroatom or carbon atom resulting in the formation of a stable structure, and the heterocyclic ring is optionally substituted with 1 to 3 substituents selected from lower alkyl, hydroxyl, nitro, amino lower alkyl amino, di (lower alkyl) amino, lower alkoxy, and lower alkyl substituted by 1 to 3 substituents selected from hydroxyl, lower alkylcarbamoyl, phenyl, halogenphenyl, heterocyclic and lower alkoxycarbonyl, lower alkoxy , a carboxy group of a lower acyl group, a lower alkylsulfonyl group, an amide group, an allyl group, a benzyl group, a phenyl group optionally substituted with an amino group, a halogen atom, a hydroxyl group, a lower group an alkoxy group, a lower alkyl group, a lower alkylamino group or a di (lower alkyl) amino group, and a heterocyclic group optionally substituted with 1 to 3 substituents independently selected from nitro, hydroxyl, lower alkoxy, lower alkyl, amino, halogen, lower alkylamino, and di (lower alkyl) amino, provided that heterocyclic group Y is not 1-imidazolyl or substituted 1-imidazolyl, (3) NR'R '' or -CH ₂ -NR'R '' wherein R 'and R''are as defined above, (4) ANR'R' ¹ and AOR 'groups, wherein A is an amino acid group or a peptide of 2 to 3 amino acid groups, and R' and R '' have the aforementioned (5) a lower 2- (alkoxycarbonyl) alkyl group, (6) a halogen atom, (7) groups of the formula R®-CHOH- in which R® is hydrogen, lower alkyl, aryl a lower arylalkyl group, a lower cycloalkyl group, a lower alkenyl group, a lower alkynyl group or a heterocyclic group, a heterocyclic ring is attached at any heteroatom or carbon atom which results in the formation of a stable structure, (8) R ⁹ -C groups (= NOR ^xo ) - in which R ¹⁰ represents a hydrogen atom, a lower alkyl group or a lower arylalkyl group and R ® represents a lower alkyl group, an aryl group, a lower arylalkyl group, a lower cycloalkyl group, a lower alkenyl group, a lower alkynyl group or a heterocyclic group a heterocyclic ring is attached at any carbon atom which results in the formation of a stable structure, (9) lower alkoxy of lower arylalkoxy, lower cycloalkoxy, lower heterocycloalkoxy or heterocyclooxy, (10) lower alkylsulfonyl, arylsulfonyl, arylsulfinyl, lower arylalkylsulfonyl, lower arylalkylsulfinyl, heterocyclo-sulfonyl, heterocyclo-sulfinyl, optionally substituted with 1 to 2 substituents selected from lower alkyl, hydroxy, halogen, nitro, nitro, nitro, nitro, nitro, nitro, nitro, NR'R ' ¹ , OC (O) R', OC (O) OR ', OC (O) NR'R'',NR' (COR '), NHC (O) NR'R''and NHC (O) OR '' where R 'and R''are as defined above, (11) groups of the formula -C (= NOH) C00R ³ · ¹ in which R ^xx represents a lower alkyl group, and (12) a hydrogen atom , substituted lower alkyl, aryl, lower arylalkyl, and lower cycloalkyl, each optionally substituted with 1 to 2 substituents selected from halogen, nitro, amino, hydroxyl, lower alkoxy, lower alkylamino lower dialkylamino groups, NR'R '', OC (O) R ', OC (O) OR', OCIONR'R '', NR '(COR'), NHCIJNR'R '' and NHC (O) OR ', wherein R' and R '' are as defined above.

A second group of compounds for use in the method of the present invention are bicyclic compounds, particularly imidazo [1,2-d] -1,2,4-thiadiazole of the following general formula II

(II), wherein R ⁵ and R ⁶ may have the same meaning as R ¹ , R ² , R ³ and R ⁴ in the above general formula II and Y is as defined above.

A third group of compounds for use in the present invention are thiadiazoles substituted at the 3-position and unsubstituted at the N-2 position of Formula III

wherein Y is as defined above and T is (a) a lower alkyl group, a lower alkylaryl group, a secondary or tertiary amino group, an amino acid group or a heterocyclic group selected from azole, pyridine, piperidine, piperazine and morpholine groups, (b) - M [-AMA-] L, where M is a chemical moiety attached to a thiadiazole nucleus and selected from the group

II

- C

H

I -N-a

II

L is an N-terminal peptide protecting group or terminal group

II

- OR ', NR'R'', - C - R' where R 'and R''are as defined above, and -ΆΜΑ- represents an amino acid or peptide group - [NH-CHA ¹ -CO] -, wherein A ¹ is any of the known amino acid í-substituents and n is a number from 1 to 3, or (c) an -NHPh group or a diphenylguanidine group of the formula

NH

II

- N - C - Ph

II

Ph in which Ph represents a phenyl group optionally substituted by a hydroxyl group, a lower alkoxy group or an amino group.

The novel monocyclic compounds for use in the present invention are thiadiazoles substituted at the 3-position and unsubstituted at the N-2 position of Formula IIa.

(IHa) wherein Y 'is lower alkyl, lower alkoxy, amino, carboxyl, lower alkoxycarbonyl or 1-piperazinyl optionally substituted at the 4-position with lower alkyl, lower alkyl with substituents selected from alkylcarbamoyl, substituted with 1 or 2 hydroxyl, lower phenyl, halophenyl, heterocyclic, carboxy and lower alkoxycarbonyl, benzyl, phenyl optionally substituted with amino, halogen, hydroxyl, lower alkoxy, lower alkyl, lower alkyl (lower alkyl) (lower alkyl) lower alkyl) amino, heterocyclic group optionally substituted with 1 to 3 substituents selected from nitro, amino, halogen, hydroxyl, lower alkoxy, lower alkyl, lower alkyl a amino group or a di (lower alkyl) amino group, a 1,1-diphenylmethyl group wherein both phenyl rings are optionally substituted with a halogen atom, an amino group, a hydroxyl group, or a lower alkoxy group, a 2-pyridyl group wherein the pyridyl ring is optionally substituted 1 to 3 substituents selected from nitro, amino, halogen, hydroxyl, lower alkoxy, lower alkyl, lower alkylamino or di (lower alkyl) amino, or -CH ₂ -CO-NH- (lower) alkyl and Q is (a) a group -T [-AMA-] L, wherein T is a chemical group

strap attached to a thiadiazole core and selected from the group consisting of 0 H OH II 1 n 1 - c - N - and - C - N - ·

L represents the N-terminal peptide protecting group or the ο terminal group

II

- OR ', NR'R''and - C - R' wherein R 'and R''are as defined above, and -AMA- represents an amino acid or peptide group - [NH-CHA ^X -CO] -, wherein A ¹ is any of the known amino acid α-substituents and n is an integer from 1 to 3, provided that when Q is NHPh then Y 'is not alkoxy, dialkylamino, hydroxyalkylamino and di (hydroxyalkyl) amino, and when Y' is a piperazinyl group substituted at the 4-position, then Q is not -T- [AMA] -L.

Another aspect of the present invention is the use of the compounds of the above formula as thiol-scavenging agents in the reaction of thiol compounds with these agents to form disulfide compounds. The reaction of the thiol compounds takes place in solution, e.g. in an aqueous medium, such as body fluids, at such temperatures and such other appropriate conditions as to maintain liquid solutions or suspensions of the reactants.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is an illustration of the chemical interaction between the thiol compounds and the 1,2,4-thiadiazolide compounds substituted at the 3-position of the present invention.

Figure 2 is an illustration of a synthetic route for preparing the most preferred compound for use in the method of the present invention.

Figure 3 is a graphical presentation of the results of Example 41 below.

Description of preferred embodiments

Preferred compounds used in the pharmaceutical methods of the present invention, i. j. upon inhibition of the proton pump enzyme by reaction of its mercaptan group, they exhibit a specification for the mercaptan functional group, as shown by the fact that the imidazo [1,2-d] -1,2,4-thiadiazole nucleus of these compounds exhibits limited or no reactivity against other nucleophiles present in vivo, such as amines and hydroxide or iodide ion. In chemical model systems, in particular, the heterocyclic ring of 1,2,4-thiadiazolo [4,5-a] benzimidazole is non-reactive towards these nucleophiles.

I particularly prefer compounds of formula I and II for use in the methods of the invention are those wherein R ^{and R6} are H, and Y is ^R CO wherein R ⁷ is lower alkyl, aryl, hydrogen or 2 -pyridyl optionally substituted with 1 to 3 substituents selected from methyl and methoxy.

A particularly interesting and preferred group of compounds of the present invention are those having amino acid or peptide side chains. These compounds may be mono-, di- or tricyclic compounds of the invention. The amino acid or peptide side chains may be attached to the bicyclic or tricyclic nucleus at position 3 of the thiadiazole ring (group Y). For monocyclic compounds, such side chains may be attached at the 3 or 5 position.

The use of amino acid or peptide groups as side chains in the monocyclic compounds used in the present invention, especially when attached to the nucleus at position 5, allows selection of the appropriate group having binding affinity for the enzyme which is inhibited by the compound. In addition, the binding affinity can be adjusted by appropriately selecting this side group so that the compound binds to the enzyme at a site on the protein chain of the enzyme adjacent to the thiol group of the enzyme being attacked by the compound. As shown below and illustrated in Figure 1 of the accompanying drawings, it is a grouping of -S-N = C- compounds of the invention, activated by an appropriately selected group Y, which is a tool for attacking a thiol compound to form a disulfide. The presence of an appropriately selected enzyme binding or recognizing group as a side chain on the compound at a position distant from the -S-N = C- group makes it possible to locate the compound and bind to the selected enzyme to increase the chemical attack of the thiol group of the enzyme. Thus, compounds of this nature of the invention are highly selective at their attack of a specific enzyme of choice and are much less reactive to other thiols they may encounter due to the presence of a recognizing side group.

A specific example of this sub-group comprises the amino acid group of the leucylisoamyl amide of formula

[-CO-leucyl-NH-isoamyl].

This group is the recognition sequence for cathepsin B and papain when positioned next to the -SH group. A compound such as 3-methoxy-5-amino-1,2,4-thiadiazole, bearing this side group bound by its 5-amino group, is therefore a good inhibitor of cathepsin L, cathepsin B and papain.

The peptide recognition sequences of cathepsin B and L may be defined as follows (see alignment in U.S. Pat

1,2,4-thiadiazole according to the present invention):

position 5

in which Y is as defined above,

A I ^x group 1 -NH-CH-CO- in everyone means the event is an amino acid, so that _Α χ eye -group known amino acids, PG means

N-protecting group selected from heterocyclocarbonyl, benzoyl, carbobenzyloxy and tert-butoxy, B ₂ is hydrogen, lower alkyl optionally substituted by amino, guanidine or N, N-di (lower alkyl) guanidine and n is a number 1 or 2.

The same group can be used in the bi- and tricyclic compounds of the present invention. A preferred -NH-CHA 4 -CO group is a leucyl group. A preferred B ₂ group is a hydrogen atom, an isoamyl group or a 4-guanidino group. A preferred PG group is carbobenzyloxy. A preferred group (CO-CHA-NH) is the dipeptide phenylalanyl-alanyl group.

For inhibiting interleukin γ3-1 converting enzyme, the recognition side chain as the compounds of the present invention is preferably a tripeptide, e.g. side chain of formula

wherein - (CO-CHA _x -NH) - is a -valinyl-alaninyl-aspartyl- group and PG is a carbobenzyloxy group, preferably attached at a position distant from the -SN = C- moiety, e.g. at position 5 of the monocyclic thiadiazole of the invention.

Other particularly preferred compounds of Formula III of the present invention include those wherein T is an amino acid group or a peptide group, e.g. compounds of formula

CH ₃

- CHS-N of the general formula

CH ₂ i

CH

^From _{CH3 CH3} especially when Y = _OCH3, of formula

compounds in which W represents an amino acid group or a peptide group of the formula AOR 'or ANR'R' ', e.g.

compounds of formula

OCH

and formula

All compounds used in the process of the present invention are characterized in that they comprise a 1,2,4-thiadiazole ring structure substituted at the 3-position and unsubstituted at the N-2 position, capable of chemically reacting with thiols to cleave the S-N bond at the 1,2-position. Assuming these properties are maintained, the range of groups and substituents at the 4 and 5 positions of the thiadiazole nucleus can be very broad without seriously affecting this substantial chemical reactivity of the compounds.

As used here:

The term lower group, as used, for example, in a lower alkyl group, means a group having 1 to 8 carbon atoms.

The term aryl, alone or in combination, means a phenyl or naphthyl group which optionally bears one or more substituents selected from an alkyl group, an alkoxy group, a halogen atom, a hydroxyl group, an amino group and the like such as phenyl, p-tolyl, 4-methoxyphenyl, 4- (tert-butoxy) phenyl, 4-fluorophenyl, 4-chlorophenyl, 4-hydroxyphenyl, 1-naphthyl, 2-naphthyl and the like.

The term arylalkoxycarbonyl, alone or in combination, means a group of the formula -C (O) -O-arylalkyl, in which the term arylalkyl has the meaning given above. An example of an arylalkoxycarbonyl group is a benzyloxycarbonyl group.

The term arylalkyl means an alkyl group in which one hydrogen atom is replaced by an aryl group such as benzyl, phenylethyl and the like.

The term cycloalkylcarbonyl means an acyl group derived from a monocyclic or branched cycloalkanecarboxylic acid, such as cyclopropanecarbonyl, cyclohexanecarbonyl, adamantanecarbonyl and the like, or from a monocyclic cycloalkanecarboxylic acid with an optionally substituted benzene group such as an optionally substituted benzene ring, e.g. 3,4-tetrahydro-2-naphthoyl and 2-acetamido-1,2,3,4-tetrahydro-2-naphthoyl.

The term arylalkanoyl means an acyl group derived from an aryl-substituted alkanecarboxylic acid such as phenylacetyl, 3-phenylpropionyl, hydroxycinamoyl, 4-phenylbutyryl, (2-naphthyl) acetyl, 4-chlorohydroamoyl, 4-aminohydro, 4-aminohydro 4-methoxyhydrocinamoyl and the like.

The term aroyl means an acyl group derived from an aromatic carboxylic acid. Examples of such groups include an aromatic carboxylic acid, optionally substituted benzoic or naphthoic acid such as benzoyl, 4-chlorobenzoyl, 4-carboxybenzoyl, 4 - [(benzoyloxy) carbonyl] benzoyl, 1-naphthoyl, 2-naphthoylic 6-carboxy-naphthoyl, 6 - ((benzyloxy) carbonyl] -2-naphthoyl, 3-benzyloxy-2-naphthoyl, 3-hydroxy-2-naphthoyl, 3 - [(benzyloxy) formamide] - 2-naphthoyl and the like.

The term heterocyclic group, as used herein, except where otherwise indicated, means a stable 5- to 7-membered mono- or bi-cyclic or stable 7- to 10-membered bicyclic heterocyclic ring which is either saturated or not saturated and containing carbon atoms and one to three heteroatoms selected from the group consisting of nitrogen, oxygen and sulfur, wherein the nitrogen and sulfur heteroatoms may be optionally oxidized and the nitrogen atom may be optionally quaternized. The term includes any bicyclic group in which any of the above heterocyclic rings is attached to the benzene ring. The heterocyclic ring may be. attached to any heteroatom or hydrogen atom, resulting in the formation of a stable structure. Examples of such heterocyclic elements, commonly known as the heterocyclic group, include piperidinyl, piperazinyl, 2-oxopiperazinyl, 2-oxopiperidinyl, 2-oxopyrolidinyl, 2-oxoazepinyl, pyrrole, 4-piperidonyl, pyrrolidinyl, pyrazolyl, pyrazolidinyl, imidazolazolinyl, imidazolazolinyl, imidazolazolinyl, imidazolazolinyl, imidazolazolinyl, imidazolazolinyl , pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, oxazolidinyl, isoxazolyl, isoxazolidinyl, morpholinyl, thiazolyl, thiazolidinyl, isothiazolyl, tetrahydrothiyl, isothiazolidinyl, indolyl, quinolinyl, benzoquinolinyl, benzoquinoline, benzoquinolyl, benzoquinoline, benzoquinoline, benzoquinoline , benzothienyl, tetrahydroquinolinyl (e.g., 1,2,3,4-tetrahydro-2-quinolinyl, etc.), 1,2,3,4-tetrahydroisoquinolinyl (e.g., 1,2,3,4-tetrahydro-1-oxo) -isoquinolyl group, etc.), quinoxalinyl ?, -carbolinyl, 2-benzofurancarbonyl, thiamorpholinyl, thiamorpholinyl sulfoxide, thiamorpholinyl sulfone, oxadiazolyl and the like. The heterocyclic ring may be substituted at one or more carbon atoms or heteroatom, resulting in the formation of a stable structure.

Amino acid groups mean any naturally include, asparagine, glutamic, lysine, but glutamine free, aspartic, glycine, methionine, ornithine, hair dryers, alanine, cysteine, cystine, histidine, isoleucine, lane, proline, serine, occurring / N, β- and γ-aminocarboxylic acids including their D and L optical isomers and their racemic mixtures and N- (lower alkyl) - and N-phenyl- (lower alkyl) derivatives of these amino acids. The amino acid group is bonded to an amino acid nitrogen atom. Naturally occurring amino acids that can be incorporated into the present invention are arginine, leucine, threonine, thyroxine, tryptophan, tyrosine, valine, -alanine and gamma-aminobutyric acid. Preferred amino acid structures include proline, leucine, phenylalanine, isoleucine, alanine, gamma-aminobutyric acid, valine, glycine and phenylglycine.

All N-amino acids, except glycine, contain at least one asymmetric carbon atom. As a result, they are optically active and exist either in D or L form as a racemic mixture. Thus, some of the compounds of the present invention can be produced in optically active form or as racemic mixtures of the compounds claimed herein.

The term A, wherein A is an amino acid group or a peptide group of 2 to 3 amino acids, refers to an amino- * acid or peptide diradical beginning with the HN group on the left side of A and terminated with the -C (O) group on the right side.

* For example, the amino acid glycine is abbreviated HAOH, where A is HN-CH ₂ -C (O).

The term aryloxyalkanoyl means an acyl group of the general formula aryl-O-alkanoyl.

The term heterocyclooxycarbonyl means an acyl group derived from a heterocyclo-O-CO-group in which the heterocyclic group is as defined above.

The term heterocycloalkanoyl means an acyl group derived from a heterocyclo- (substituted alkane) carboxylic acid in which the heterocyclic group is as defined above.

The term heterocycloalkoxycarbonyl means an acyl group derived from (heterocyclic-substituted alkyl) -O-COOH, wherein the heterocyclic group is as defined above.

The term aminoalkanoyl means an acyl group derived from an amino-substituted alkanecarboxylic acid in which the amino group may be:

primary, secondary or tertiary containing substituents selected from the group consisting of amino, hydrogen, alkyl, aryl, arylalkyl, cycloalkyl, cycloalkylalkyl and the like.

Pharmaceutically acceptable non-toxic salts means the pharmaceutically acceptable salts of the compounds of the invention that retain the biological activity of the parent compounds and are not biologically or otherwise undesirable (e.g., those salts are stable). The compounds of the present invention can form salts of the following two types:

1) salts of inorganic and organic bases of compounds of formula I having a carboxylic acid functional group,

2) acid addition salts that can be formed on the amine function of many of the compounds of the invention.

Pharmaceutically acceptable salts derived from inorganic bases include sodium, potassium, lithium, ammonium, calcium, magnesium, ferrous, zinc, copper, manganese, aluminum, ferric, manganese, and the like. Particularly preferred are the ammonium, potassium, sodium, calcium and magnesium salts. Pharmaceutically acceptable, non-toxic salts derived from organic bases include salts of primary, secondary, and tertiary amines, substituted amines including naturally occurring substituted amines, cyclic amines, and basic ion exchange resins. Examples of such salts are isopropylamine, trimethylamine, diethylamine, triethylamine, tripropylamine, ethanolamine, 2-dimethylaminoethanol, trometamine, dicyclohexamine, lysine, arginine, histidine, caffeine, procaine, hydrabramine, choline, methyl, glucosamine, ethylenediamine, ethylenediamine. piperazine, piperidine, N-ethylpiperidine, polyamine resins and the like. Particularly preferred organic non-toxic bases are isopropylamine, diethylamine, ethanolamine, piperidine, tromethamine, dicyclohexylamine, choline and caffeine.

«** ·

Pharmaceutical produce with such hydrochloric, propionic acid, sulfonic acid, sulfonic acid, acceptable addition salts with inorganic acids, hydrobromic acid, nitric acid, phosphoric acid, and acids such as glycolic acid, oxalic acid, malic acid, succinic acid maleic, tartaric, citric, cinnamic, mandelic, ethanesulfonic, salicylic and the like.

with acids such as sulfuric acid, the like, and orgaacetic acid, pyruvic acid, malonic acid, fumaric acid, benzoic acid, p-toluenesulfonic acid methanoic acid mean humans equally species, especially mammals (e.g.

The term livestock, pigs, etc.), reptiles, fish, insects and like other dogs, cats, horses, nematodes.

Some specific, most preferred of the present invention are as follows:

compounds according to

3- (1-oxoethyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole of the following chemical formula

ABOUT

3- (oxophenylmethyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole of the following chemical formula

ph

3- (2-pyridyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole of the following chemical formula

3- (4-Methyl-1-piperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole of the following chemical formula

Me

3- (4-morpholinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole of the following chemical formula

3- (1-pyrrolidinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole of the following chemical formula

3-Bromo-1,2,4-thiadiazolo [4,5-a] benzimidazole of the following chemical formula

- [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole of the following chemical formula

3-carboxy-1,2,4-thiadiazolo [4,5-a] benzimidazole of the following chemical formula

7-methoxy-3 - [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole of the following chemical formula

CH _} 0

CH,

OCH j

3- (4-Methylphenylsulfonyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole of the following chemical formula

CH ₃

3- (1-oxoethyl) imidazo [1,2-d] -1,2,4-thiadiazole of the following chemical formula

O-C

CH ₃

3- (Oxophenylmethyl) imidazo [1,2-d] -1,2,4-thiadiazole of the following chemical formula

C = 0

P h

3- (4-Acetyl-1-piperazinyl-1,2,4-thiadiazolo [4,5-a] benzimidazole of the following chemical formula

3- [4- (3-amino-2-pyridyl) piperazinyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole of the following chemical formula

3- (4- (2-pyridyl) piperazinyl-1,2,4-thiadiazolo [4,5-a] benzimidazole of the following chemical formula

3- [4- (3-amino-2-pyridyl) piperazinylmethyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole of the following chemical formula

3- [4- (2-pyridyl) piperazinylmethyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole of the following chemical formula

3 - {[4- (1- (4-chlorophenyl) -1-phenylmethylpiperazinyl] methyl} -1,2,4-thiadiazolo [4,5-a] benzimidazole of the following chemical formula

(3-Methoxy-1,2,4-thiadiazol-5-yl) carbamoyl-L-leucylisoamylamide of the following chemical formula

5- [carbobenzyloxy-L-phenylalanyl-L-alanine-amide] -3-methoxy-1,2,4

-thiadiazole of the following chemical formula

OMe

O ^P \ HO nA

PhCH ₂ . _o A ^^ N- ^ A ^ X _S '

HO CH ₃ H

The present invention provides synthetic methods for making the compounds of the invention. Some of these methods involve converting one compound of the invention to another, different compound. The choice of method depends largely on the desired group Y, i. j. at the 3-position substituent of the final compound.

The imidazo [1,2-d] -1,2,4-thiadiazole compounds and compounds of formula IV described in these processes, X and Z are R ^B or ^R, or together are a benzene ring fused to the imidazo optionally monosubstituted with R ¹ substi26 , R ^2, R ³ and R ^4th

According to a first method which is applicable to bi- or tricyclic compounds, the corresponding 3-oxo compound of formula V (below), bearing a lower alkyl or lower arylalkyl substituent at the 2-position, is reacted with YCN in an inert solvent. This method is suitable for compounds wherein Y is lower alkyl, aryl, arylalkyl, cycloalkyl, 1-haloalkyl, 1,1-dihaloalkyl, heterocyclic, lower alkylsulfonyl or arylsulfonyl. The reaction can be illustrated as follows:

(IN)

The corresponding YCN nitrile compounds in which Y is lower alkyl, aryl, arylalkyl, cycloalkyl, 1-haloalkyl, 1,1-dihaloalkyl, lower alkylsulfonyl, arylsulfonyl, or heterocyclic are, for example, commercially available. . They can also be produced by methods known in the art (see, for example, Chapter 17 of the Organic Functional Group Preparation, Volume I, by Sandler and Kara, Academic Press, 1983). Some typical examples are acetonitrile, benzonitrile, 2-cyanopyridine, cyclopentyl cyanide, dibromoacetonitrile, 6-cyanopurine and p-toluenesulfonyl cyanide. The reaction normally proceeds at elevated temperature, between 70 to 140 ° C in an inert solvent such as toluene and dimethylformamide, for 6 to 24 hours, preferably 16 hours. In some cases, the compound of formula YCN is used as the solvent. The product is isolated by conventional means.

Compounds of formulas I and II, i. j. bicyclic and tricyclic compounds wherein Y is amino, lower alkylamino, lower dialkylamino or thioalkyl may also be produced using compounds of formula YCN wherein Y is amino, lower alkylamino, lower dialkylamino or lower thioalkyl group. Examples of compounds of formula YCN in this category are cyanamide, 11-piperidinecarbonitrile and methylthiocyanate, which are commercially available. Compounds of formula YCN may also be synthesized from cyanogen bromide according to literature procedures (see page 174, Fieser and Fieser: Reagents in Organic Synthesis, John Wiley and Sons, 1967).

2-Alkyl-1,2,4-thiadiazolo [4,5-a] benzimidazol-3 (2H) -ones of formula V are prepared from alkyl isocyanate and 2-mercaptobenzimidazole according to the method of Martin et al., Tetrahedron 1983, 39, 2311 2-Alkylimidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) -ones of formula V are prepared from alkyl isocyanates and 2-mercaptoimidazole according to the procedure of Tittlebach et al., J. Prakt. Chem. 1988, 330, 338-34.

The 2-mercaptobenzimidazoles are either commercially available or can be produced by methods well known in the art or readily. available from the literature. Commercially available 2-mercaptobenzimidazoles include 5-methyl-2-mercaptobenzimidazole, 5-methoxy-2-mercaptobenzimidazole and 5-chloro-2-mercaptobenzimidazole. Suitable 2-mercaptobenzimidazoles, which are not commercially available, can be produced by known methods. Preparative methods include those described by: Billeter et al., Chem. Ber. 1887, 20,231, Org. Synth. Coli. Vol. 4.

569, Futaki et al., J. Pharm. Soc. Jap. 1954, 74, 1365, and Bucknall et al., Nature 1967, 213, 1099.

In a second similar method, applicable to the preparation of bicyclic and tricyclic compounds in which the

Y in the final compound is ^R-C = O and R ⁷ is lower alkyl, aryl, lower arylalkyl, lower cycloalkyl, lower alkoxy, amino, lower alkylamino, lower dialkylamino, heterocyclic, wherein the heterocyclic the ring is a carbon atom, and a NR'R ¹ 'group, attached to any heteroatom or results in the formation of a stable structure, or AOR', wherein A represents an amino acid group or a peptide of 2 to 3 amino acid groups and R 'and R''have as defined above, is a compound of formula

reacting with the corresponding 3-oxo compound bearing a lower alkyl or lower arylalkyl substituent at the 2-position, i. j. the compound of formula (V) used in the first process above, i.e.

(IN)

This reaction may be carried out in an inert solvent such as dichloromethane, tetrahydrofuran or dimethylformamide. The reaction proceeds at room temperature for 3 to 48 hours, usually about 6 hours. The resulting solid is then isolated by conventional means.

Most of the cyanketones, cyanester derivatives of formula VI, are commercially available. The cyanoketone derivatives used in the present invention are either commercially available or can be produced by methods known in the art. Commercially available cyanoketones include benzoyl cyanide, acetyl cyanide, and methoxycarbonyl cyanide. A list of commercially available cyanide derivatives is available (Chem. Sources, USA, 24th edition, 1983, Directories Publishing Company Inc., Ormont Beach, Fla.). Appropriate cyanoketones, cyanesters not commercially available, can be readily prepared by methods known in the art, such as those described in: Mathieu et al., Formation of C-C Bonds, Vol. I, p. 456-457, George Thieme Verlag, 1973, Stuttgart. Other suitable methods include those described by Koenig et al., Tetr. Lett. 1974, 2275, and Andoom et al., Synthesis 1983, 637. These J methods include the reaction of an acid chloride with cuprous cyanide or potassium cyanide.

l

Compounds of formula I in which Y represents a group R ' ⁷ -C = O, in which R ^v is as defined above, can also be prepared by hydrolysis of compounds of formula I in which Y represents a group R ⁱⁿ -C (Hal) ₂ wherein Hal represents a halogen atom. Such hydrolysis may be carried out in a strongly acidic medium or in aqueous silver nitrate and may be illustrated as follows:

Y

Hal — ý — Hal R7

A third process for preparing imidazole and benzimidazole products with Y groups as in the second process described above comprises, as a final step, reacting the 2-thioether-diazole compound of formula VI with m-chloroperbenzoic acid (MCPBA) in an inert solvent. This results in cyclization to form the 1,2,4-thiadiazole ring. This can be illustrated as follows:

(VII)

(VI)

The bromo-heterocycloacetonitrile derivative of formula VII can be reacted with a 2-mercaptobenzimidazole of formula VIII in principle to give a compound of formula VI. Examples of such bases are sodium hydroxide or potassium hydroxide. The reaction is carried out in a mixture of water and alcohol at room temperature for about 1 to 16 hours, preferably 8 hours. The compound of formula (VI) is isolated as a product by conventional means.

The compound of formula VI is reacted with m-chloroperbenzoic acid in an inert solvent such as dichloromethane or 1,2-dichloroethane. This yields a compound of formula (I) wherein Y is R ' ⁷ -C = O. The reaction proceeds at room temperature for about 3 to 8 hours, preferably 3 hours. The product is isolated by conventional means.

The bromo-heterocycloacetonitrile derivative of formula VII is prepared by reacting a compound of formula X with N-bromosuccinimide in an inert solvent such as carbon tetrachloride.

The fourth method uses a compound of formula IA as the starting material and derivatizes it to a compound of formula I wherein Y is -CHOH-R ⁷ (compound of formula IB) or -C = NOH-R ⁷ (compound of formula IC) or -COOH (compound of formula ID), i.e.:

Compounds of formula IB of the corresponding compounds' R ⁷ -C = O, (IC) may be prepared by reduction of formula IA in which the sodium compound is treated with sodium cyanoborohydride in alcohol.

Formula IB is isolated by conventional methods.

Compounds of formula (IC) may be prepared by reacting a compound of formula (I) wherein Y is R ' ⁷ -C = O with hydroxylamine derivatives. Examples of hydroxylamines include hydroxylamine, methoxylamine, ethoxylamine and benzyloxyamine. The conversion of ketone to oxime is well documented in the art (see, for example, Sandler and Kara: Organic Functional Group Preparations, 1989, Volume III, Chapter 11).

Compounds of formula (ID) in which R @ ⁷ is hydroxyl may be prepared by basic hydrolysis of compounds of formula (I) in which Y is R @ ⁷ -C.dbd.O and R @ ⁷ is lower alkoxy. The reaction is carried out in 1M sodium hydroxide at room temperature in a mixture of water and an organic solvent such as methanol, ethanol, 1,4-dioxane or acetonitrile. This product is isolated by conventional acid.

by methods following the method of Formula I and Formula II employing Formula V, neutralization of the base by dilution is applicable to the preparation of compounds of the invention in which the same starting point used in the first and

The fifth general halogen atom of the general formula (V) as it is and reacts with a halocyanate, i.e.:

Y represents the compound in the second (V)

* N

X-s of N 'o

This reaction is carried out in an inert solvent. The compound is isolated by conventional methods.

The sixth method uses as starting materials compounds of formula Ia and II in which Y is a halogen atom, e.g. the compounds obtainable according to the fifth method above and reacted with a secondary amine or an alcohol of formula I wherein Y is ANR'R '' or OR '. R 'and R' 'have the most meaning when the bromine atom is present.

or OR '. the process proceeds with the material means, with the primary or the formation of the compound, the group NR'R '', AOR 'mentioned above. This Y in the default

It can therefore be represented as follows:

Y

They are

Nucleophiles such as arylalkoxides, lower amines, lower dialkylamines, HANR'R '' and HAOR ', in which A lower cycloalkoxides, ammonia, heterocyclic amines, HNR'R''means an amino acid residue alkoxides, aryloxides, lower lower alkylamines, or a peptide 2 to 3 amino acid residues are reacted with compounds of formula I wherein Y is bromo in an inert solvent to form compounds of formula I wherein Y is lower alkoxy, aryloxy, lower arylalkoxy, lower cycloalkoxy, amino, lower alkylamino a lower dialkylamino group, an NR'R ' ¹ , ANR'R''orAOR' group, wherein A is an amino acid group or a peptide group of 2 to 3 amino acid groups.

The seventh method uses compounds of formula Ia and II according to the invention in which Y is COOH (obtainable according to the fourth method above) as starting materials and reacts with an amine to form a compound of formula I in which Y is CO-R ^Where R ^v is NR'R ¹ ', AOR' or ANR'R '', ie:

In this way, compounds of formula I and II wherein Y is R ' ⁷ -C = O and R ⁷ is NR'R'',AOR' or ANR'R '' can be produced by reaction of a carboxylic acid compound of the general formula of formula I wherein Y is COOH, with an amino acid amide of formula HANR'R '', amines of formula HNRR '' or amino acid esters of formula HAOR 'in the presence of a dehydrating agent such as 1- (3-dimethylaminopropyl) -3 ethylcarbodiimide (EDCI) and hydroxybenzotriazole, in an inert solvent such as tetrahydrofuran, dimethylformamide or dichloromethane.

Eighth method applicable to the preparation of compounds in which

Y represents a lower alkylsulfonyl group, arylsulfonyl group, a heterocyclo-sulfonyl group, a lower arylalkylsulfonyl group, a lower alkylsulfinyl group, an arylsulfinyl group, a heterocyclo-sulfinyl group or a lower arylalkylsulfinyl group, comprising the reaction of the corresponding compound in the thioether

wherein n is an integer of 1 agent for use according to perbenzoic acid (MCPBA), suitable oxidizing agents.

or this but

2. The preferred oxidation process is m-chlorosiston many others

One preferred method of the invention is to inhibit the enzyme, in vitro or in vivo, and specifically to inhibit the proton pump H * / K * -ATPase enzyme to treat gastric ulcers in humans. The major development in the treatment of peptic ulcers has been realized by the introduction of H * / K * -ATPase inhibitors. The H * / K * -ATPase enzyme, also known as the proton pump, is located in the gastric parietal cell membrane and is responsible for the transfer of protons from the blood to the lumen, further leading to a decrease in the pH of the stomach contents and leading to deterioration of peptic ulcers. . Efficiency. The method of the present invention in the uptake of this enzyme and thus in obtaining means for treating peptic ulcers is demonstrated in the specific examples below. However, the methods of the present invention are applicable. for a variety of other chemical systems • scavenging thiols, both biochemical (enzymatic) and industrial, as listed below for their reactivity with phenethyl mercaptan.

Since the thiadiazole compounds capture the thiol group containing compounds by forming an S-S bond, they may be modifiers of the SH cysteine group. Thus, thiol-scavenging agents can be used as affinity labels in the chemical modification of cysteine groups on the enzyme. Since these compounds can function as affinity labels on enzymes containing cysteine groups, they are useful inhibitors of many physiological enzymes such as cathepsin B, papain, interleukin-beta-1 converting enzyme and protein disulfide isomerase (HIV), as well as H * / K * -ATPase. Since enzyme pathways are involved in various physiological and disease states, the compounds of the invention have potential therapeutic use.

Thiol-scavenging agents can also react with a cysteine group on enzymes and proteins and thus alter the biochemical properties of this enzyme. Thiol-scavenging agents can be useful stabilizers and enhancers of cysteine-containing enzymes. Examples of some of these therapeutically important enzymes are PC1 convertase, furin, (see O'Rabilly S. et al., New England Journal of Medicine 1995, 23, 1386-1390). PC1 is the convertase responsible for processing proglucanone to GLP-1 peptide. GLP-1 regulators may be useful therapeutic agents for the treatment of diabetes and obesity. The compounds of the invention are thiol-scavenging agents and can be used as stabilizers and enhancers of cysteine-containing enzymes.

The reactivity of the compounds in the method of the invention can be illustrated by their reaction with phenethyl mercaptan. This reaction is generally illustrated in Figure 1 of the accompanying drawings, wherein R of the thiol reagent is a phenethyl group. In addition, based on the knowledge of the art [Im et al .: J. Biol. Chem. 1985, 260, 4591; Sturm. et al., J. Org. Chem. 1987, 52, 4573; Lorentzon et al., Biochim. Biophys. Acta 1985, 817, 25.) Phenethylmercaptan is a useful model in

H '/ K'-ATPase to investigate the reactivity of compounds with the thiol group (s) of the enzyme. Compounds of formula I have been found to react with phenethylmercaptan (RSH = PhCH ₂ CH ₂ SH, Fig. 1) in an inert solvent to give a compound of formula XI. The compound of formula XI is reacted with another mole of phenethylmercaptan to form a compound of formula XII which decomposes to give compounds of formula XIII and XIV.

A minimum of two moles of phenethyl mercaptan per mole of substrate is required to effect ring opening of 1,2,4-thiadiazolo [4,5a] benzimidazoles to give a compound of formula XII. In general, the ring opening reaction is slow with two moles of phenethyl mercaptan. The reaction rate is rapidly increased when a large excess of phenethyl mercaptan is used (e.g., twenty-five times). It was found that the compounds used in the present invention react rapidly with phenethyl mercaptan according to the procedure shown in Figure 1. The disulfide could not be isolated as it was found to react rapidly with the second mercaptan to form the phenethyl mercaptan disulfide and the illustrated intermediate. This degradation of the thiol-trapped intermediate to form a disulfide was also observed in the H * / K * -ATPase chemical model (Lindberg et al., J. Med. Chem. 1986, 29, 1329.). It should be noted that in the actual enzyme, the second step, which involves the attack of another thiol group, would not occur due to steric factors preventing access of the two enzymes, or would lead to disulfide bond formation if another nearby thiol group were present . In both cases, this would lead to inhibition of the enzyme.

According to the present invention, it has been found that a compound such as 3-methoxy-5-amino-1,2,4-thiadiazoles reacts with benzyl mercaptan in an organic solvent such as methanol to give 3-thiocarbamoylmethoxyisourea:

PhCHjSH

PhCHjSH

+ PhCH ₂ SSCH ₂ Ph

Other 1,2,4-thiadiazoles such as 3-methyl-5-dibenzylamino-1,2,4-thiadiazole, 3-methyl-5-benzylamino-1,2,4-thiadiazole and 3,5di (3-pyridyl) -1,2,4-thiadiazole, do not react with benzyl mercaptan under similar conditions. The chemical activity of monocyclic 1,2,4-thiadiazole as a thiol scavenger depends on the substituent at the 3 and 5 position of the cyclic system.

1,2,4-Thiadiazolo- [4,5-a] benzimidazole derivatives undergo similar reaction with mercaptans

Y

intermediate

Y = Ph-COMcOH + Ph-CO-COOMe

When RSH is thiophenol, the resulting Ph-S-S-Ph dimer can be isolated. This reaction is also general for various 1,2,4-bicyclic and tricyclic 1,2,4-thiadiazoles with different substituents at the 3-position of the heterocycle.

Preferred compounds used in the methods of the invention are heterocycles having a molecular weight of less than 440. The log P spectrum of these molecules, i. j. the shaking coefficient between octanol and water is between 0.5 and 4.0, which includes the range of lipophilicity of most known drugs. These are important factors in the development of therapeutic agents and reflect the fact that individual analogs may have potential use as therapeutic agents in diseases in which inhibition of thiol-group-containing enzymes is a potential solution for treating the disease.

The specificity of the compounds used in the present invention for mercaptan demonstrated by the fact that these in the functional group methods are compounds exhibiting limited or no reactivity to other nucleophiles present in vivo, such as amines, hydroxide or iodide ions. In chemical model systems, the 1,2,4-thiadiazolo [4,5-a] benzimidazole heterocyclic ring is unreactive to these nucleophiles.

One specific, preferred compound for use in the methods of the present invention is 7-methoxy-3 - [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl] -1,2,4-thiadiazolo [4,5- a] benzimidazole. This molecule carries an electroattractive group at the 3-position of the heterocyclic ring. It has limited solubility in water. Its structure was proved by X-ray analysis. ^X H and ¹³ C NMR spectroscopy, IR, mass spectrometry and elemental analysis provided further evidence of possible chemical identity of this compound. Further specific details of its preparation, characterization and properties are set forth in the specific examples below. This compound is active in suppressing gastric acid secretion in an animal model.

For the treatment of peptic ulcers, the compounds of the invention may be administered orally, topically or parenterally in dosage unit formulations containing conventional, non-toxic, pharmaceutically acceptable carriers, adjuvants and diluents. The term parenteral as used herein includes subcutaneous injection or infusion techniques. In addition to treating warm-blooded animals such as mice, rats, horses, cattle, sheep, dogs, cats, etc., these compounds are effective in treating humans.

The compositions include conventional, non-toxic solid carriers which may be used, for example, mannitol, lactose, starch, magnesium stearate, sodium saccharin, talc, cellulose, glucose, sucrose, magnesium carbonate, and the like, all of pharmaceutical purity. The active compound as above can be prepared as liquid pharmaceutically acceptable preparations, for example prepared by dissolving, the active compound and dispersing, etc. of the above optional pharmaceutical, said adjuvant can be in a carrier such as water, saline, aqueous dextrose, glycerol, ethanol and the like so as to form a solution or suspension. If desired, the pharmaceutical composition to be administered may also contain minor amounts of nontoxic excipients such as wetting or emulsifying agents and the like, for example sodium acetate, sorbitan monolaurate, triethanolamine sodium acetate, trietaloamine oleate, etc. Methods the manufacture of these dosage forms is known or will be apparent to those skilled in the art: for example, see Remington's Pharmaceutical Sciences, Mack Publishing Company,

Easton, Pa., 15th Edition, 1975. The composition of the composition to be administered will in any case contain an amount of the active compound (s) that is effective to alleviate the symptoms in the subject being treated.

Pharmaceutical compositions containing the active ingredient may exist in a form suitable for oral use, for example, as tablets, pills, lozenges, aqueous or oily suspensions, dispersible powders or granules, emulsions, hard and soft capsules, or syrups or elixirs. The formulations to be used orally may be manufactured by any method known in the art for the manufacture of pharmaceutical formulations. Such formulations comprise one or more agents selected from the group consisting of sweetening agents, flavoring agents, coloring agents and preservatives to provide pharmaceutically acceptable and palatable preparations. Tablets contain the active ingredient in admixture with non-toxic pharmaceutically acceptable excipients which are suitable for the manufacture of a tablet. Excipients may be, for example, inert diluents, such as calcium phosphate or sodium phosphate, granulating and disintegrating agents, for example corn starch or alginic acid, binding agents, for example starch, gelatin or acacia, and lubricating agents, for example magnesium stearate, stearic acid or talc . The tablets may be coated by known methods to delay disintegration and absorption in the gastrointestinal tract and thereby achieve a sustained action over a long period of time. Monostearate or glyceryl distearate may be used.

Oral formulations may also exist as hard gelatin capsules in which the active ingredients are mixed with an inert solid diluent, for example calcium phosphate or kaolin, or as soft gelatin capsules in which the active ingredient is mixed with water or an oil medium, for example peanut oil, liquid paraffin or olive oil.

Aqueous suspensions contain the active materials in admixture with excipients suitable for the manufacture of aqueous preparations. These excipients are suspending agents, for example sodium carboxymethylcellulose, methylcellulose, hydroxypropylmethylcellulose, sodium alginate, polyvinylpyrrolidone, gums, and acacia, the dispersing or wetting agents may be naturally occurring phosphate, for example lecithin, stearate polyoxylate, condensate polyoxyethylene stearate products, for example acids, condensation products of ethylene oxide with long-chain aliphatic alcohols, for example heptadecatyl-enoxycetanol, or condensation of fatty acids and hexitol anhydrides, for example monooleate products of ethylene oxide with partial esters derived from polyethylene sorbitan. Aqueous suspensions may also contain one or more preservatives, for example ethyl, propyl or p-hydroxybenzoate, and one or more coloring agents, such as sucrose or saccharin.

Oily suspensions may be prepared by suspending the active ingredient in a vegetable oil, for example arachis oil, olive oil, sesame oil or coconut oil, or in a mineral oil such as liquid paraffin. The oily suspensions * may contain a thickening agent, for example beeswax, hard paraffin or cetyl alcohol. Sweetening agents such as the aforementioned sweetening agents and flavoring agents may be added to provide a palatable oral preparation. These compositions may be protected by the addition of an antioxidant such as ascorbic acid.

Dispersible powders and water provide wetting granules suitable for the manufacture of an aqueous active ingredient in admixture with a reagent, suspending agent or multiple preservatives. Examples of dispersing or wetting and suspending agents are those already mentioned above. Other agents may be present, for example, sweetening, flavoring suspensions by addition with dispersing or more and one suitable agent as well as coloring agents.

The pharmaceutical composition of the invention may exist in the form of oil-in-water emulsions. The oily phase may be a vegetable oil, for example olive oil or oil, or a mineral oil, for example liquid or mixtures thereof.

also means peanut paraffin, or mixtures thereof. Suitable emulsifying agents may be naturally occurring phosphates, fatty acid esters and hexitol anhydrides, for example monooleate and condensation products of said partial ethylene oxide, for example polyoxyethylene monooleate. The emulsion may also contain sweetening sorbitan, sorbitan esters.

and flavoring agents.

Syrups and elixirs may be prepared with sweetening agents, for example glycerol, propylene glycol, sorbitol or sucrose. These preparations may also contain soothing agents, preservatives, flavoring and coloring agents. The pharmaceutical preparations can be prepared by methods known in the art using the appropriate dispersing or wetting and suspending agents as mentioned above. Sterile injectable preparations may also exist as a sterile injectable solution or suspension in a nontoxic, parenterally acceptable diluent or solvent, for example, as a solution in 1,3-butanediol. Acceptable diluents and solvents that may be used include water, Ringer's solutions and isotonic sodium chloride solution. Conventionally, fixed oils are also used as a solvent or suspending medium, any mixture of fixed or diglycerides.

Fatty acids, such as oleic acid, may also be used for this purpose, including synthetic mono- or injectable preparations.

Parenteral administration is usually by injection, either subcutaneously, intramuscularly or intravenously. Injectable preparations may be made in conventional forms, either as liquid solutions or suspensions in liquid prior to administration. by injection, or as an emulsion. Suitable excipients are, for example, water, saline, dextrose, glycerol, ethanol or the like. If desired, the pharmaceutical preparations to be administered may also contain minor amounts of non-toxic excipients such as wetting or emulsifying agents, pH buffering agents and the like, such as sodium acetate, sorbitan monolaurate, triethanolamine oleate, etc. ..

The amount of active ingredient that may be combined with the carrier materials to produce a single dosage form will vary depending upon the host treated. A particular route of administration to humans may include 0.5 mg to 5 g of active agent in admixture with an appropriate and conventional amount of carrier material, which will range from about 5 to about 95% of the total formulation. Unit dosage forms will generally contain from about 1 mg to about 500 mg of the active ingredient.

However, it is to be understood that this specific dosage amount for any particular patient will depend on a variety of factors including the efficacy of the specific compound employed, age, body weight, general health, sex, diet, duration of administration, drug combination and severity of the underlying disease. therapy.

The invention is further described and illustrated by the following specific examples.

DETAILED DESCRIPTION OF THE INVENTION

Example 1

Production of bromo (2-pyridyl) acetonitrile

To a solution of (2-pyridyl) acetonitrile (12.0 g, 0.10 mol) in 150 mL of carbon tetrachloride was added 18.1 g of N-bromosuccinimide (0.10 mol) at room temperature. The mixture was refluxed for 1.5 hours. The resulting precipitate was removed by filtration and the solvent was removed under reduced pressure. The crude product is recrystallized from hexane. There was thus obtained 18.6 g (94%) of the title compound as red crystals, mp 62-64 ° C. ^X H-NMR _(DMSO-d6, d): 8.67 (d, 1H), 7.97 (t,

1H), 7.70 (d, 1H), 7.51 (td, 1H), 5.60 (s, 1H) ppm. IR (KBr): 3064, 2972, 1712, 1587, 1470, 1439, 1051 and 993 cm ^{@ -1} . Mass spectrum (m / z): 196, 198 (M < ⁺ &^gt;), 117 (M < ^{+ >)}

- Br). HRMS calcd for C ^ HH ^ Br BrNN: 195.9630, found: 195.9645.

Proceeding in a similar manner, the following compound was prepared: bromo (4-methoxy-3,5-dimethyl-2-pyridyl) acetonitrile: mp 56-57 ° ^{C; H} NMR (CDC13, d): 8.31 ( s, 1H), 5.67 (s, 1H), 3.81 (s, 3H), 2.37 (s, 3H), 2.30 (s, 3H) ppm. ¹³ C NMR spectrum (CDCl 3, δ '): 164.84, 150.19, 149.56, 128.28, 125.59, 115.49, 60.135, 27.99, 13.51, 11.05 ppm. IR (KBr): 3415, 2988, 2210, 1568, 1472, 1255, 997 and 791 cm @ ^-1 . Mass spectrum (m / z): 255, 257 (M +), 175 (M + - Br).

Example 2

Synthesis of [(2-benzimidazolyl) thio] (2-pyridyl) acetonitrile

A mixture of 2-mercaptobenzimidazole (0.30 g, 3.0 mmol), bromo (2-pyridyl) acetonitrile (0.59 g, 3.0 mmol) and potassium carbonate (0.37 g, 3.0 mmol) in 50 ml of dry N, N-dimethylformamide was heated at 60 ° C for 6 hours. The solvent was evaporated. The residue was dissolved in ethyl acetate, washed with water and then with saturated sodium chloride solution. The organic layer was dried over magnesium sulfate. Evaporation gave a solid product. This crude product was further purified by silica gel column chromatography (eluting with 100% ethyl acetate). 60 mg (10 £) of the title compound as a solid, mp 166-167 ° ^{C; H-NMR} (DMSO-d _e,): 9.3 (m, 1H), 8.65 (m (2H), 8.32 (m, 1H), 7.78 (br s, 2H) ppm. IR: 2026, 1512, 1465, 1432, 1357, 1179, and 740 cm ^{@ -1} .

In a similar manner, but substituting 2-mercaptoimidazole for 2-mercaptobenzimidazole, the following compound was prepared: [(2-imidazolyl) thio] (2-pyridyl) acetonitrile: mp 203-204 ° C (dec.). ^X H NMR (CDC13, d): 8.51 (d, 1H), 7.65 (t, 1H), 7.36 (d, 2H), 7.12 (d, 1H), 7.03 ( dd, 1H), 6.33 (br s, 2H) ppm. ¹³ C NMR (CDCl 3, d 6): 154.08, 148.23, 145.76, 136.84, 134.95, 134.43, 119.15, 118.40, 109.32, 95.15 ppm . IR (KBr): 3344, 3225, 2205, 1643, 1493, 1485, and 1427 cm @ ^-1 .

Example 3

Synthesis of [(5-methoxy-2-benzimidazolyl) thio] (4-methoxy-3,5-dimethyl-2-pyridyl) acetonitrile

To a solution of 2-mercapto-5-methoxybenzimidazole (15.1 g, 0.14 mol) dissolved in 40 mL of 8.4% sodium hydroxide was added 170 mL of methanol and bromine (4-methoxy-3,5-dimethyl-2- pyridyl) acetonitrile (21.4 g, 0.11 mol) at room temperature. The mixture was heated under reflux for 1 hour under a nitrogen atmosphere. The resulting precipitate was removed by filtration and the methanol was evaporated. The residue is extracted with chloroform. The chloroform was washed three times with water and dried over anhydrous magnesium sulfate. After evaporation of the solvent, the crude product is recrystallized from diethyl ether. This afforded 22.6 g (90%) of the title compound as yellowish crystals, mp 193-197 ° C. ^X H NMR _(CDCl3, d): 8.25 (s, 1H), 7.65 (dd, 1H), 7.30 (m, 1H), 6.90 (m, 1H), 6.30 (broad s, 2H), 3.95 (s, 3H), 3.75 (s, 3H), 2.50 (s, 3H), 2.20 (s, 3H)

3H) ppm.

Example 4

Synthesis of 3- [oxo (2-pyridyl) methyl] imidazo [1,2-d] -1,2,4-thiadiazole

To a solution of [(2-imidazolyl) thio] (2-pyridyl) acetonitrile (30 mg, 0.14 mmol) in 5 mL chloroform was added portionwise 0.12 g of 60% m-chloroperbenzoic acid (0.42 mmol). The mixture was stirred at room temperature for 10 hours. The resulting mixture was washed with water and saturated sodium bicarbonate solution. The organic phase is then treated with activated carbon and filtered off. A crude product is obtained. Chromatography on silica gel (eluting with 100% ethyl acetate) afforded 22 g (84%) of the title compound as a yellowish solid, m.p.

mp 147-148 ° C. ^X H NMR _(CDCl3, d): 8.87 (d,

1H), 8.30 (m, 2H), 7.95 (m, 1H), 7.57 (m, 1H), 7.52 (m, 1H) ppm. IR (KBr): 1700 and 1660 cm ^@ -1. Mass spectrum (m / z): 230 (M < ^{+ >} ). HRMS - to C _IQ H ₆ N ₄ OS Calcd 230.0262, found: 230.0267.

Example 5

Synthesis of 7-methoxy-3 - [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole and 6-methoxy-3 - [( 4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl] -1,2,4-thiadiazole [4,5-a] benzimidazole

To a solution of [(5-methoxy-2-benzimidazolyl) thio] (4-methoxy-3,5-dimethyl-2-pyridyl) acetonitrile (5.31 g, 15 mmol) in 400 mL of chloroform was stirred at 0 ° C for 1 h. 60% m-chloroperbenzoic acid (8.62 g, 30 mmol) dissolved in 100 mL of chloroform was added dropwise to 5 ° C. After the addition was complete, the reaction mixture was stirred at room temperature for one hour. The resulting mixture was then washed with water and dried over magnesium sulfate. The solvent was evaporated. A crude product is obtained. Silica gel chromatography (eluting with ethyl acetate / hexane 1: 1) gave 0.828 g (10%) of 7-methoxy-3 - [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl] -1,2 4-thiadiazolo [4,5-a] benzimidazole as a yellowish solid and 0.828 g (10%) of 6-methoxy-3 - [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl] -1 2,4-thiadiazolo [4,5-a] benzimidazole as a solid.

7-Methoxy-3 - [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl] -1,2,4-thiadiazole [4,5- a] benzimidazole: mp 170-171 ° C ^X H NMR spectrum (DMSO-d _e, d): 8.34 (s, 1H), 7.86 (d, 1H), 7.29 (d, 1H), 6.93 (dd, 1H), 3.84 (s, 6H), 2.42 (s, 3H), 2.31 (s, 3H) ppm. IR (KBr): 1684 and 1654 cm ^{@ -1} . Mass spectrum (m / z): 369 (M + +1).

6-Methoxy-3 - [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole: mp 196-197 ° C. ^X H-NMR _(DMSO-d6, delta): 8.34 (s, 1H), 7.67 (d, 1H), 7.34 (d, 1H), 7.10 (dd, 1 H), 3 84 (s, 3H), 3.74 (s, 3H), 2.44 (s, 3H), 2.31 (s, 3H) ppm. IR (KBr): 1684 cm ^{@ -1} . Mass spectrum (m / z): 369 (M + +1).

Example 6

Synthesis of dibromo (2-pyridyl) acetonitrile

To a solution of (2-pyridyl) acetonitrile (6.0 g, 50.8 mmol) in 120 mL of carbon tetrachloride was added N-bromosuccinimide (18.5 g, 104 mmol) at room temperature. The resulting mixture was refluxed for 22 hours. After cooling, the precipitate was filtered off. The carbon tetrachloride was evaporated. There was thus obtained 13.5 g (96%) of dibromo (2-pyridyl) acetonitrile as a dark brown solid, mp 59-61 ^° C. ¹ H NMR spectrum (CDCl 3, δ): 8.62 (d, 1H), 7.93 (d, 1H), 7.86 (dt, 1H), 7.35 (dt, 1H), ppm. ¹³ C NMR (CDCl 3, δ): 155.23, 148.94, 138.24, 125.38,

120.55, 115.81, 30.81 ppm. HRMS calculated for C C HH ^N ^Br ^:

273.8741, found: 273.8730.

Example 7

Synthesis of 2-butyl-1,2,4-thiadiazolo [4,5-a] benzimidazol-3 (2H) -one

A mixture of 2-mercaptobenzimidazole (29.30 g, 0.195 mole) and butyl isocyanate (48.3 mL, 0.33 mmol) in a 500 mL round bottom flask equipped with a condenser was heated in an oil bath at 130-140 ° C for 45 min. After cooling the reaction mixture to room temperature, the solid was filtered off, washed with hexane and dried in vacuo. 43.48 g (89%) of 1- (butylcarbamoyl) -1,3-dihydrobenzimidazole-2-thione are obtained in the form of white crystals, m.p. t. Mp 179-180 ° C.

To a solution of 1- (butylcarbamoyl) -1,3-dihydrobenzimidazole-2-thione (39.89 g, 0.16 mol) in 250 mL chloroform at 0 ° C was added 25.57 g (0.16 mol) bromine in 110 ml of chloroform. After the addition was complete, triethylamine (44.6 mL, 0.32 mol) in 80 mL of chloroform was added dropwise to the reaction mixture. The mixture was stirred for an additional 4 hours at 0 ° C. It is then stirred at room temperature for 14 hours. The resulting mixture was washed first with water and then with 10% sodium sulfate solution. The organic layer was dried over magnesium sulfate and evaporated. A crude product is obtained. Recrystallization from methanol gave 27.10 g (69%) of 2-butyl-1,2,4-thiadiazolo [4,5-a] benzimidazol-3 (2H) -one as colorless crystals, mp 153-154 ° C [literature (Martin et al., Tetrahedron 1983, 39, 2311.): 156-157 ^° C].

In a similar manner, but substituting butyl alkyl isocyanates with other alkyl isocyanates, the following compounds were prepared:

2-Ethyl-1,2,4-thiadiazolo [4,5-a] benzimidazol-3 (2H) -one, 2-isopropyl-1,2,4-thiadiazolo [4,5-a] benzimidazol-3 (2H) ) -one, 2-methyl-1,2,4-thiadiazolo [4,5-a] benzimidazol-3 (2H) -one, 2-phenyl-1,2,4-thiadiazolo [4,5-a] benzimidazole -3 (2H) -one and 2-benzyl-1,2,4-thiadiazolo [4,5-a] benzimidazol-3 (2H) -one.

Example 8

Synthesis of 3- [dibromo (2-pyridyl) methyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole

A mixture of 2-butyl-1,2,4-thiadiazolo [4,5-a] benzimidazol-3 (2H) -one (2.0 g, 8.1 mmol) and dibromo (2-pyridyl) acetonitrile (4.91) g (17.8 mmol) in 50 ml of dichloromethane is heated under reflux for 16 hours. After cooling to room temperature, the precipitate was filtered off, washed with dichloromethane and dried. Thus, 2.76 g (80%) of the title compound are obtained as a pale brown solid, mp 195 ° C (dec.). ^X H NMR (CDC1, d): 8.25 (m,

2H), 7.96 (dt, 1H), 7.76 (d, 1H), 7.32 (m, 2H), 6.95 (t, 1H),

6.92 (s, 1 H) ppm. ¹³ C NMR spectrum (CDCl ₃ , δ): 166.08,

157.95, 150.34, 148.28, 147.71, 138.31, 128.76, 124.79,

124.58, 122.94, 121.68, 119.49, 113.97 and 54.37 ppm. HRMS - to C _{x <i} H _e Br ₂ N ₄ S Calcd: 421.8836, Found: 421.8850.

Example 9

Synthesis of 3- (oxophenylmethyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole

A mixture of 2-butyl-1,2,4-thiadiazolo [4,5-a] benzimidazol-3 (2H) -one (6.0 g, 24.3 mmol) and benzoyl cyanide (6.36 g, 48.5 mmol) ) in 80 ml of dichloromethane is stirred at room temperature. The precipitate was filtered off and washed with dichloromethane. The crude product was recrystallized from acetone. To obtain 6.48 g (96%) of 3- (oxofenylmetyl) -1,2,4-thiadiazole [4,5-] benzimidazole as yellow crystals, mp 190-191 ° ^{C; H-NMR} (CDC1 _3, 8.35 (d, 3H), 7.82 (d, 1H), 7.73 (t, 1H), 7.59 (t, 2H), 7.50 (t, 1H), 7, 36 (t, 1H). ¹³ C NMR spectrum (CDCl 3 _/ δ): 180.86, 163.69, 150.82, 146.70, 134.79, 134.34, 131.22 (2C), 129.46 (2C), 128.74, 125.82, 122.27, 119.49 and 115.23 ppm. IR (KBr): 1671 cm ~ ^x. HRMS - _is the C H ₃ N ₃ OS calc : 279.0466, found: 279.0475. found C, H, _{is of} N ₃ OS calculated: 64.50% C, 3.25% H, 15.04% N found: 63.93% C, 3.10 % H, 14.53% N.

In a similar way, when the benzoyl cyanide is replaced with pyruvic acid nitrile, the following compound is produced:

- (1-oxoethyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole, mp 180-181 ° C. ^X H NMR (CDC13, d): 8.70 (d, 1H), 7.80 (d, 1H), 7.50 (t, 1H), 7.38 (t, 1H), 2.83 ( s, 3H). ^X3 C NMR spectrum (CDCl3, d '): 187.02, 164.15, 150.69, 147.78, 129.63,

125.82, 122.26, 119.27, 115.94 and 26.74 ppm. IR (KBr): 1703 cm ^"x. HRMS - _xq for C H ₇ N ₃ OS Calculated: 217.0310, Found: 217.0318. To C _io H _at N ₃ OS Calculated: 55.29% C, 3.25% H, 19.34% N Found: 55.31% C, 3.29% H, 19.46% N.

In a similar way, when the benzoyl cyanide is replaced by other cyanides, the following compounds are produced:

3- (1-oxopropyl) -1,2,4-thiadiazole [4,5-a] benzimidazole,

3- (l-oxobutyl) -1,2,4-thiadiazole [4,5-a] benzimidazole,

3- (1-oxo-2-phenylethyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole, 3- (cyclopentyloxomethyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole and 3- (l-oxo-2-phthalimidoethyl) -1,2,4-thiadiazole [4,5- a] benzimidazole.

Example 10

Synthesis of 3-methyl-1,2,4-thiadiazolo [4,5-a] benzimidazole

2-Butyl-1,2,4-1-thiazolo [4,5-a] benzimidazol-3 (2H) -one (1.00 g, 4.04 mmol) was refluxed in 100 mL of acetonitrile for 18 hours. The solvent was then evaporated. The residue was recrystallized from methanol. To obtain 0.671 g (88%) of the title compound, mp 192-193 ° ^{C; H-NMR} _(CDCl3, d): 7.81 (dm, 2H), 7.47 (td, 1H), 7.34 (td, 1H); 2.92 (s, 3H) ppm. IR (KBr): 1564, 1481, 1453,

1430, 1304, 1208, 756 and 745 cm ^-1 . Mass spectrum (m / z):

185 (M +), 148 (M + - CH _and CN).

In a similar manner, but substituting acetonitrile with other alkyl nitriles, the following compounds were prepared:

3-ethyl-1,2,4-thiadiazolo [4,5-a] benzimidazole, 3-isopropyl-1,2,4-thiadiazolo [4,5-a] benzimidazole and 3- (2-methylpropyl) -1, 2,4-thiadiazole [4,5- a] benzimidazole.

Example 11

Synthesis of 3- [4- (methoxycarbonyl) phenyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole

A mixture of 2-butyl-1,2,4-thiadiazolo [4,5-a] benzimidazol-3 (2H) -one (0.3 g, 1.2 mmol) and 4-cyanobenzoic acid methyl ester (0.41 g, 2.5 mmol) in 7 ml of dichloromethane was heated under reflux for 20 hours. The precipitate was filtered off and washed with dichloromethane. There was thus obtained 3- [4- (methoxycarbonyl) phenyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole (0.16 g, 48%) as a white solid, mp 204-206 ° C. ^X H-NMR (CDCl3, d): 8.33 (d, 2H), 7.98 (d, 2H), 7.83 (d, 1H), 7.49 (m, 2H), 7.20 ( t, 1H), 4.02 (s, 3H) ppm. ¹³ C NMR spectrum (CDCl 3,

δ): 165.96, 165.30, 151.08, 149.10, 133.16, 132.55, 130.24 (2C), 128.69 (3C), 125.34, 121.58, 119 , 96, 112.01 and 52.56 ppm. IR (KBr): 1729, 1508, 1448, 1275 and 733 cm @ ^-1 . HRMS

- for C _{i6 xi} H N ₃ O ₂ S Calculated: 309.0572, Found: 309.05719.

Example 12

Synthesis of 3- (4-methylphenylsulfonyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole

A mixture of 2-butyl-1,2,4-thiadiazolo [4,5-a] benzimidazol-3 (2H) -one (10.0 g, 40.4 mmol) and p-toluenesulfonyl cyanide (14.7 g, 81%), (0 mmol) in 120 ml of dichloromethane is stirred for 20 hours at room temperature. The precipitate was filtered off and washed with dichloromethane. There was thus obtained 12.2 g (91%) of 3- (4-methylphenylsulfonyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole as a white-

him powder , t. t. 231 až 8.53 (d, 1H), 8.04 (d, 4H), 2.53 (s, 3H) ppm. 150.38. 147.97. 147.54. 128.49, 126.14. 123.06. spectrum (KBr): 1592

234 ^{0 C; H-NMR} (CDC1 _3, d):

7.82 (d, 1H), 7.56 to 7.44 (m, (CDC1 _3, δ): 163.72, (2C), 129.97 (2C), and 21.93 ppm. IR 1151, 1081 and 735

2H), ^x3 C NMR spectrum

132.48.

119.70.

1525, 1444

130.30

114.67

1337, cm ^-1 . HRMS - to C _is H, _{I, L 3} N ₂ 0 ₂ S Calculated: 329.0293, Found: 329.0300. The C H _{1 S XX} N ₃ O ₂ S ₂ Calculated: 54.70% C, 3.37% H, 12.76% N Found: 54.29% C, 3.14% H, 14.59% N .

Example 13

Synthesis of 3- (methoxycarbonyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole

A mixture of 2-butyl-1,2,4-thiadiazolo [4,5-a] benzimidazol-3 (2H) -one (4.0 g, 16.2 mmol) and methyl cyanoformate (2.75 g, 32.4 mmol) ) in 30 ml of dichloromethane is stirred for 21 hours at room temperature. The precipitate was filtered off and washed with dichloromethane. To obtain 3.36 g (84%) of 3- (methoxycarbonyl) -1,2,4-thiadiazole [4,5-] benzimidazole as a colorless solid, mp 208-209 ^{0 C; H} NMR ( CDCl 3, δ: 8.61 (d, 1H), 7.82 (d, 1H), 7.51 (t, 1H), 7.31 (t, 1H), 4.17 (s, 3H) ppm . ^X3 C NMR spectrum (CDCl3, δ): 164.02, 156.51, 150.67, 140.89, 129.34, 125.93, 122.41, 119.48, 115.41 and 54.04 ppm . IR (KBr): 1733 cm ~ ^x. HRMS - for

C ₁₀ H 11 N ₃ O ₂ S calculated: 233.0259, found: 233.0262. To ^C io ^H 7 ^N ° 2 p ^S Calculated: 51.50% C, 3.02% H, 18.02% N Found: 51.41% C, 2.89% H, 18.16% N.

In a similar manner, but substituting methyl cyanoformate for other cyanoformates, the following compounds were prepared: 3- (ethoxycarbonyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole, 3- (butoxycarbonyl) -1,2 4-thiadiazolo [4,5-a] benzimidazole, 3- (isopropoxycarbonyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole, 3 - [(benzyloxy) carbonyl] -1,2,4- thiadiazolo [4,5-a] benzimidazole and 3 - [(cyclopentyloxy) carbonyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole.

Example 14

Synthesis of 3- (2-pyridyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole

A mixture of 2-butyl-1,2,4-thiadiazolo [4,5-a] benzimidazol-3 (2H) -one (15.0 g, 60.7 mmol) and cyanopyridine (13.3 g, 0.13 mmol) ) in 150 ml of dichloromethane is stirred for 72 hours at room temperature. The precipitate was filtered off and washed with dichloromethane. There was thus obtained 3- (2-pyridyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole (10.4 g, 68%) as a white solid, mp 173-174 ° C. ^X H-NMR (CDC1 _3, 8): 8.90 (d, 1H), 8.70 (d,

1H), 8.30 (d,

7.47 (t,

166.10.

125.85, spectrum

1H),

151.09.

125.24 (KBr):

1H), 7.99 (t

7.37 (t

1H) (1H, ppm). ¹³

150.11.

124.52.

3419 3054

7.80 (d, 1H), 7.57 (t, 1H), ³ C NMR spectrum (CDCl ₃ , d '):

148.74, 147.73, 137.38, 130.50,

121.41, 119.11 and 116.33 ppm. Company ID

1611, 1587, 1501, 1463, 1446 and 727 cm ^-1 . HRMS - to C _i3 H _{Step 4} S Calculated: 252.0470, Found: 252.0882. H, 3.20; N, 22.21. Found: C, 61.48; H, 3.30; N, 22.24.

Example 15

Synthesis of 3-amino-1,2,4-thiadiazolo [4,5-a] benzimidazole

To a cooled solution of 2-butyl-1,2,4-thiadiazolo [4,5-a] benzimidazol-3 (2H) -one (2.0 g, 8.08 mmol) in 25 mL of dichloromethane was added cyanide (0.728 g). (12.6 mmol) in one portion and the mixture is stirred at room temperature for 48 hours. The resulting precipitate was filtered, slurried with methanol and then washed with dichloromethane to give 1.01 g (66%) of 3-amino-1,2,4-thiadiazolo [4,5-a] benzimidazole as colorless crystals, mp 255-256 ° ^{C; H-NMR} (DMSO-d,): delta 8.23 (d, 1H), 7.71 (d, 1H), 7.43 (t, 1H), 7 54 (s, 2H); 7.32 (t, 1H) ppm. IR (KBr): 3302, 3151,

1661, 1577, 1487, 1473, 1251, 1207 and 810 cm ^x . HRMS - to C * _and H ₆ N ₄ S Calcd: 190.0313, Found: 190.0293. The C _and H _of N ₄ S Calculated: 50.51% C, 3.18% H, 29.45% N Found:

% C, 50.26;% H, 3.26;% N, 29.38.

Example 16

Synthesis of 3-bromo-1,2,4-thiadiazolo [4,5-a] benzimidazole

A mixture of 2-butyl-1,2,4-thiadiazolo [4,5-a] benzimidazol-3 (2H) -one (5.0 g, 20.2 mmol) and cyanogen bromide (4.28 g, 40.4 mmol) ) in 100 ml of dichloromethane was stirred at room temperature for 26 hours. The precipitate was filtered off and washed with dichloromethane. To obtain 4.18 g (81%) of 3-bromo-l, 2,4-thiadiazole [4,5-] benzimidazole as a white powder, mp 189-190 ° ^{C; H-NMR} _(CDCl3, d ': 8.23 (d, 1H), 7.82 (d, 1H), 7.52 (t, 1H), 7.42 (d, 1H) ppm. ^{X 3} C NMR spectrum (CDCl ₃ with DMSO-d ₆ in 1: 1, δ): 162.78, 149.67, 129.22, 125.53, 122.25,

119.48, 117.25, 111.27 ppm. IR (KBr): 3025, 2925.

1601, 1493, 1451, 1028, 757, and 701 ^x CNT. HRMS calcd for C _and H ₄ N ₃ SBr: 252.9309, found: 252.9307. For C _and H ₄ N ₃ SBr calculated: 37.81% C, 1.59% H, 16.54% N, found:

% C, 37.44;% H, 1.33;% N, 16.57.

In a similar way, but substituting cyanogen bromides with other halogens, the following compounds were produced:

3-Iodo-1,2,4-thiadiazolo [4,5-a] benzimidazole a

3-chloro-l, 2,4-thiadiazole [4,5- a] benzimidazole.

Example 17

Synthesis of 3- [oxo (2-pyridyl) methyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole

To a solution of 3- [dibromo (2-pyridyl) methyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole (2.02 g, 4.76 mmol) in 75 mL of tetrahydrofuran is added a solution of silver nitrate ( 0.890 g, 5.24 mmol) in 75 mL of water. The suspension was stirred for 2 days and then basified with aqueous sodium bicarbonate to pH 6. After addition of 1 ml of saturated aqueous sodium chloride, the mixture was filtered through celite and the celite was washed with ethyl acetate. After extraction with water, the ethyl acetate is dried and evaporated. The crude residue was purified by flash chromatography, eluting with 1: 1 chloroform: methanol. This afforded 1.05 g (78%) of the title compound as a yellow solid, mp 182-186 ^° C (dec.). ^X H-NMR (CDC1 _3, d): 8.85 (m, 1H), 8.31 (dt, 1 H), 8.19 (d, 1H), 8.01 (td, 1H), 7.83 (d, 1H), 7.63 (ddd, 1H), 7.50 (ddd, 1H), 7.35 (ddd, 1H) ppm. IR (film): 1673, 1511, 1444, 1235, 1057, 879, and 733 cm ^{@ -1} . Mass spectrum (m / z): 280 (M +), 148 (M + - (2-pyridyl) C (O) CN).

Example 18

Synthesis of 3- [bis (ethoxycarbonyl) methyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole

A mixture of 3-bromo-1,2,4-thiadiazolo [4,5-a] benzimidazole (0.2 g, 0.78 mmol), diethyl malonate (0.15 g, 0.94 mmol) and triethylamine (0.13) ml (0.94 mmol) in 8 ml tetrahydrofuran was refluxed for 36 hours under a nitrogen atmosphere. The resulting mixture was extracted with ethyl acetate, washed with water and 10% aqueous sodium sulfate. The organic layer was dried over magnesium sulfate. The crude product was purified by flash chromatography (35% ethyl acetate with 65% hexane). This afforded 0.14 g (54%) of the title compound as a yellow oil. ^T H NMR (CDC1 _3, s): 9.48 (s, 1H), 8.06 (d, 1H), 7.63 (d, 1H), 7.34 7.31 (m, 2H) 4.39 (q, 4H), 1.35 (t, 6H) ppm. IR (film): 1748 cm @ ^-1 . HRMS calcd for C ^ HH NN ^O ^S: 333.0783, found 333.0794.

Example 19

Synthesis of 3-methoxy-1,2,4-thiadiazolo [4,5-a] benzimidazole

To a cooled mixture of 3-bromo-1,2,4-thiadiazolo [4,5-a] benzimidazole (4.55 g, 17.9 mmol) in 50 mL of methanol was added sodium methoxide (0.967 g, 17.9 mmol) in one portion. ). The mixture was stirred at room temperature for 4 hours. The reaction mixture was evaporated to dryness in vacuo. The residue was taken up in ethyl acetate and washed with water. The organic layer was dried over sodium sulfate, filtered and evaporated. To obtain 3.64 g (94%) of 3-methoxy-l, 2,4-thiadiazole [4,5-] benzimidazole as colorless crystals, mp 172-175 ° ^{C; H} NMR Spectrum (CDC1 _3, cT): 7.83 (d, 1H), 7.75 (d, 1H), 7.42 (t,

1H), 7.27 (t, 1H), 4.32 (s, 3H) ppm. ¹³ C NMR spectrum (CDCl ₃ ,

δ): 163.2, 150.3, 148.1, 128.2, 124.9, 121.8, 119.2, 111.7 and 57.5 ppm. IR (KBr): 3418, 2942, 1595, 1492, 1404, 1275, 1255, 1206, 1083, and 755 cm ^{@ -1} . For C _g H ₇ N ₃ OS Calculated: 52.67% C, 3.44% H, 20.49% N Found: 52.28% C, 3.36% H,

20.45% N.

In a similar manner, but substituting sodium methoxide with other metal alkyloxides, the following compounds were prepared: 3-ethoxy-1,2,4-thiadiazolo [4,5-a] benzimidazole, 3-propoxy-1,2,4 thiadiazole [4,5-a] benzimidazole,

3-isopropoxy-1,2,4-thiadiazolo [4,5-a] benzimidazole, 3-butoxy-1,2,4-thiadiazolo [4,5-a] benzimidazole,

3-tert-butoxy-1,2,4-thiadiazolo [4,5-a] benzimidazole a

3- (cyclopentyloxy) -1,2,4-thiadiazole [4,5- a] benzimidazole.

Example 20

Synthesis of 3- (dimethylamino) -1,2,4-thiadiazolo [4,5-a] benzimidazole

To a cooled solution of 3-bromo-1,2,4-thiadiazolo [4,5-a] benzimidazole (15.44 g, 0.0603 mmol) in 100 mL of dichloromethane was added dropwise dimethylamine (40% solution in water) ( 5.44 g, 0.121 mmol). The reaction mixture is left under stirring at room temperature for 16 hours. It is then diluted with dichloromethane, washed with water, dried over sodium sulphate and evaporated in vacuo. To obtain 10.47 g (80%) of 3- (dimethylamino) -1,2,4-thiadiazole [4,5-] benzimidazole as colorless crystals, mp 102-104 ° ^{C; H-NMR} (CDC1 _{3. (} 5 '): 7.74 (t, 2H), 7.41 (t, 1H), 7.27 (t, 1H), 3.06 (s, 6H) ppm. % C, 4.62% H, N 25.69. Found: C 54.53, H 4.90, N 25.50.

In a similar manner, but substituting dimethylamine with other amines, the following compounds were prepared:

3- (ethylamino) -1,2,4-thiadiazolo [4,5-a] benzimidazole, mp 164.5-165 ^° C (dec.). ^X H-NMR (CDC1 _3, d): 7.78 (m, 2H), 7.65 (d, 1H), 7.43 (t, 1H), 7.21 (t, 1H), 3.68 (q, 2H), 1.45 (t, 3H) ppm.

3- (1-pyrrolyl) -1,2,4-thiadiazole [4,5- a] benzimidazole: mp 118-119 ^{0 C; H-NMR} (CDC1 _3, d): 7.77 (t, 2H) 7.43 (t, 1H); 7.28 (t, 1H); 3.71 (m, 4H); 2.07 (m, 4H) ppm.

3- (4-morpholinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole, m.p. t.

140-142 ^° C (dec.). ^X H-NMR (CDC1 _3, d): 7.78 (d, 1H), 7.60 (d, 1H), 7.45 (t, 1H), 7.32 (t, 1H), 3.99 (m, 4H), 3.48 (m, 4H) ppm.

3- (1-piperazinyl) -1,2,4-thiadiazole [4,5- a] benzimidazole: mp 116-118 ° ^{C; H-NMR} _(CDCl3, <r): 7.76 (d, 1 H ), 7.63 (d, 1H), 7.42 (t, 1H), 7.30 (t, 1H), 3.41 (m, 4H), 3.15 (t, 4H), 2.00 (broad s, 2H) ppm.

3- (4-methyl-1-piperazinyl) -1,2,4-thiadiazole [4,5-a] benzimidazole,

mp 158-158.5 ° C. ^X H-NMR (CDC1 _3, d): 7.77 (d, 1H), 7.64 (d, 1H), 7.42 (t, 1H), 7.32 (t, 1H), 3.49 (m, 4H), 2.70 (m, 4H), 2.43 (s, 3H) ppm.

3 - [[2- (methoxycarbonyl) methyl] amino] -1,2,4-thiadiazolo [4,5-a] benzimidazole, mp 196-197 ^° C. For CH NOS calculated: 50.37% C, 3, Found:% C, 50.13;% H, 3.96;% N, 21.26.

In a similar manner, but replacing dimethylamine with other nucleophilic amines, the following compound was prepared: 3- (methylamino) -1,2,4-thiadiazolo [4,5-a] benzimidazole.

Example 21

Synthesis of 3 - [(hydroxyimino) phenylmethyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole

To a solution of 0.5 g (1.79 mmol) of 3- (oxophenylmethyl-1,2,4-thiadiazolo [4,5-a] benzimidazole in 7 ml of ethanol is added 0.5 ml (6.46 mmol) of pyridine and 0.5 g (7.2 mmol) of hydroxylamine hydrochloride The mixture is refluxed overnight, the precipitate is filtered off and washed with methanol and dichloromethane to give a crude product which is recrystallized from methanol to give 0.47 g. (89%) of the title compound as white crystals, mp 247 ° ^{C; H-NMR} (DMSO-d _e, d): 11.89 (s, 1H), 7.81 (d, 1 H), 7 73 (dd, 1 H),

7.45 to 7.53 (m, 5H), 7.32 (t, 1H) ppm. ¹³ C NMR (CDCl ₃ , δ): 168.25, 155.24, 150.52, 147.95, 136.94, 135.67,

134.30 (2C), 133.03, 131.52 (20, 130.35, 127.26, 124.28 and 116.91 ppm. IR spectrum (KBr): 2731, 1549, 1475, 1450,

1251, 1194, 983, 753 and 736 cm ^-1 . HRMS calcd for CHN OS: 294.0575, found: 294.0583.

Example 22

Synthesis of 3- (1-hydroxyethyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole

To a suspension of 3- (1-oxoethyl-1,2,4-thiadiazolo [4,5-a] benzimidazole (729 mg, 3.36 mmol) in 200 mL of methanol was added sodium borohydride (140 mg, 3.69 mmol). The mixture is stirred for 30 minutes, 0.1 ml of water is added, the methanol is evaporated and the residue is partitioned between ethyl acetate and 0.1M hydrochloric acid, the aqueous phase is extracted with ethyl acetate, the organic phases are combined, washed twice with brine, The crude residue was purified by chromatography eluting with chloroform-methanol to give 3- (1-hydroxyethyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole, mp 174-175 ° C. ^X H

NMR _(CDCl3, d): 8.05 (d, 1H), 7.80 (d, 1H), 7.47 (td,

1H), 7.36 (td, 1H), 5.39 (q, 1H). , 2.76 (d, 1H) and 1.84 (d, 3H) ppm. IR (KBr): 3136, 1544, 1494, 1478, 1451, 1374,

1250, 1200, 1123, 1103, 1093, 752, 729 and 711 ^cm-x. Mass spectrum (m / z): 219 (M &lt; ^{+ &gt;} ), 148 (M &^lt; ⁺ &^gt; -CH _and CH (OH) CN).

Example 23

Synthesis of 3-carboxy-1,2,4-thiadiazolo [4,5-a] benzimidazole

To 6 mL of 1 N NaOH solution was added 3- (methoxycarbonyl) -1,2,4-thiadiazolo [4,5- a] benzimidazole (1.0 g, 4.3 mmol) in 6 mL dioxane. The reaction mixture was stirred at room temperature until completion of the reaction. The resulting mixture was then acidified with 3N HCl to a pH of about 2.0 and stirred at room temperature for an additional 0.5 hour. The solid was filtered off, washed with water and dried in vacuo. at 60 ^° C for 24 hours. Yield 0.74 g (78%) of the title compound as a colorless solid, mp 184-185 ° C (dec.). ^X H-NMR (DMSO-d, delta): 13.79 (br s, 1H), 8.59 (d, 1H), 7.78 (d, 1H), 7.51 (t, 1H), 7 40 (t, 1 H) ppm. IR (KBr) 3435 and 1705 cm @ ^-1 . Mass spectrum (m / z): 193 (M + - OH), 175 (M + - CO 2).

Example 24

Synthesis of 3-carboxylate-1,2,4-thiadiazolo [4,5-a] benzimidazole sodium salt

To a suspension of 3-carboxy-1,2,4-thiadiazolo [4,5-a] benzimidazole (10.00 g, 45.62 mmol) in methanol (150 mL) and water (100 mL) was added IM over 1 hour. NaOH (45.6 mL). After 4 hours the solution became clear. The methanol was removed under reduced pressure. The aqueous solution is extracted with chloroform and the aqueous phase is freeze-dried. To obtain the title compound (10.4 g, 95%) as a white solid, mp 225-227 ° ^{C; H-NMR} _(DMSO-d6, d): 7.68 (d, 1H) , 7.05 (d, (t, 1H) ppm. ¹³ C NMR spectrum)

149.68, 148.84, 129.52, 126.23, IR (KBr): 3395, 3243,

827 and 729 cm ^-1 .

Example 25

6.95 (t, 1H), 6.80 (DMSO- _d <5): 167.20, 161.76, 122.74, 118.37, 116.06 ppm. 1663, 1641, 1522, 1443,

Preparation of 3- (4-methyl-1-piperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole dihydrochloride

A clear solution of 3- (4-methyl-1-piperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole (6.07 g, 22.21 mmol) in 100 mL dichloromethane was bubbled with hydrogen chloride gas for 40 min. . The solution becomes cloudy over time. The suspension is filtered and dried under vacuum. Obtained as a fine white powder (7.60 g, 99%), mp 252 ^° C (dec.). ^X H-NMR (DMSO-D 2 O, and S): 7.85 (d, 2H), 7.60 (t, 1H), 7.51 (t, 1H), 3.86 (m, 2H); 3.56 (m, 6H) and 2.91 (s, 3H) ppm. ¹³ C NMR spectrum (DMSO-d6 and D ₂ O, δ): 164.39, 148.80, 144.27, 126.92, 126.12, 123.41, 117.08, 113.20, 51 , 59, 45.87 and 42.32 ppm. IR spectrum (KBr): 3420, 1606, 1571, 1475, 1461, 1225, 981 and 761 cm ^{@ -1} .

Example 26

Preparation of 2-butylimidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) -one

2-Mercaptoimidazole (24.39 g, 0.244 mol) and butyl isocyanate (48.6 g, 0.487 mol) were combined in a round-bottom flask and heated to 50 ° C for 30 minutes or until the reaction was complete. terminated (according to TLC). The reaction mixture is then cooled to room temperature and the solidified is triturated with 50 ml of hexane for 30 minutes. The beige material was filtered off, washed with a minimum amount of hexane and dried under reduced pressure. There was thus obtained 44.96 g (93%) of 1- (butylcarbamoyl) -1,3-dihydroimidazole-2-thione as beige crystals, mp 66-68 ^° C.

To a solution containing 1- (butylcarbamoyl) -1,3-dihydroimidazole-2-thione (4.73 g, 23.7 mmol), suspended in 15 mL of dichloromethane at 0 ^° C under nitrogen, is added bromine dropwise. (3.79 g, 23.7 mmol) dissolved in 15 mL of dichloromethane. As soon as the addition is complete, triethylamine (4.81 g, 47.5 mmol) dissolved in 15 mL of dichloromethane is added such that the temperature of the reaction mixture never exceeds 0 ^° C. The reaction mixture is maintained at 0 ° C for an additional two hours and then stirred for 16 hours at room temperature. It is diluted with 150 ml of dichloromethane and washed twice with water and once with saturated sodium chloride solution. The organic layer was then dried over magnesium sulfate and evaporated to dryness. 4.30 g (92%) of 2-butylimidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) -one are obtained in the form of an off-white powder, mp 142-143 [deg.] C. ^X 1 H NMR Spectrum (CDCl ₃ , d): 7.40 (d, 1H), 7.20 (d, 1H), 3.79 (t, 2H), 1.73 (m, 2H), 1.40 ( m, 2H) and 0.957 (t, 3H) ppm. IR (KBr) 1702 cm ^{@ -1} .

In a similar manner, but substituting butyl isocyanate with other selected isocyanates, the following compounds were prepared:

2-methylimidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) -one, 2-ethylimidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) - One, 2-propylimidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) -one, 2-isopropylimidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) ) -one, 2-pentylimidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) -one, 2-hexylimidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) -one, 2-cyclohexylimidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) -one, and

2-Benzylimidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) -one.

Example 27

Synthesis of 3- (1-oxoethyl) imidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) -one

To a cooled solution of 2-butylimidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) -one (2.49 g, 12.6 mmol) in 5 mL of dichloromethane was added dropwise pyruvic nitrile (1). (74 g, 25.2 mmol) and allowed to stir. 24 hours. The precipitate was filtered off, washed with dichloromethane and evaporated under reduced pressure. 0.662 g (31%) of 3- (1-oxoethyl) imidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) -one is obtained in the form of yellow-green crystals, mp 142-144 ^{0 C; H-NMR} (CDC1 _3, delta): 8.23 (s, 1H), 7.51 (s, 1H), 2.78 (s, 3H). IR (KBr) 3436, 3168,

3106, 1516, 1408, 1363, 1229, 1136 and 730 cm ^-1 . H, 3.01; N, 25.13. Found:

H, 2.91; N, 25.27.

In a similar manner, but substituting benzoyl cyanide for pyruvic nitrile, the following compound was prepared: 3- (1-oxophenylmethyl) imidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) -one,

mp 166-168 ° C. ¹ H NMR spectrum (CDCl ₃ , cc): 8.44 (d, 2H), 8.40 (s, 1H), 7.70 (d, 1H) and 7.58 ( t, 3H) ppm.

In a similar way, but substituting pyruvic acid nitrile with another selected cyanide or nitriles, the following compounds were produced:

3- (1-oxopropy1) imidazo [1,2-d] -1,2,4-thiadiazole-3 (2H) -one

3- (1-oxobutyl) imidazo [1,2-d] -1,2,4-thiadiazole-3 (2H) -one

3- (1-oxopentyl) imidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) -one; 3- (1-oxohexyl) imidazo [1,2-d] -1,2 , 4-thiadiazole-3 (2H) -one

3- (cyclopentyloxomethyl) imidazolyl, 2-d] -1,2,4-thiadiazol-3 (2H) -one, and

- (l-oxo-2-phthalimidoethyl) imidazo [1,2-d] -1,2,4-thiadiazole-3 (2H) -one.

Example 28

Synthesis of 3- (methoxycarbonyl) imidazo [1,2-d] -1,2,4-thiadiazole

To a cooled solution of 2-butylimidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) -one (2.95 g, 15.0 mmol) in 25 mL of dichloromethane was added dropwise methyl cyanoformate (2.54). g, 30 mmol) and the mixture was stirred at room temperature for 16 hours. The precipitate was filtered off and then washed with dichloromethane. To obtain 2.18 g (80%) of 3- (methoxycarbonyl) imidazo [1,2-d] -1,2,4-thiadiazole as colorless crystals, mp 164.5 to 165 ⁰ C ^X H NMR (CDCl ₃ , δ T): 8.13 (s, 1H), 7.51 (s, 1H), 4.11 (s, 3H) ppm. IR (KBr) 3440, 1737, 1527, 1253 and 1071 cm @ ^-3 . For

_C, H, _{N 3} O ₂ S -vypočítané: 39.34% C, 2.75% H, 22.94% N Found: 39.41% C, 2.51% H, 22.94% N.

In a similar way, but replacing methyl cyanoformate with other cyanoformates, the following compounds were produced:

3- (ethoxycarbonyl) imidazo [1,2-d] -1,2,4-thiadiazole,

3- (propoxycarbonyl) imidazo [1,2-d] -1,2,4-thiadiazole,

3- (butoxycarbonyl) imidazo [1,2-d] -1,2,4-thiadiazole,

3- (isopropoxycarbonyl) imidazo [1,2-d] -1,2,4-thiadiazole,

3 - [(pentyloxy) carbonyl)] imidazo [1,2-d] -1,2,4-thiadiazole,

3 - [(cyclopentyloxy) carbonyl)] imidazo [1,2-d] -1,2,4-thiadiazole; and

- [(benzyloxy) carbonyl)] imidazo [1,2-d] -1,2,4-thiadiazole.

here

Example 29 v

Synthesis of 3-bromoimidazo [1,2-d] -1,2,4-thiadiazole

To a cooled solution of 2-butylimidazo [1,2-d] -1,2,4-thiadiazol-3 (2H) -one (4.78 g, 0.0242 mmol) in 25 mL of dichloromethane was added cyanogen bromide (5, 13 g, 0.0482 mmol). The mixture was stirred at room temperature for 16 hours. The precipitate is filtered off, suspended in 10 ml of methanol and washed with dichloromethane. There was thus obtained 3.45 g (90%) of 3-bromoimidazo [1,2-d] -1,2,4-thiadiazole as a colorless powder, mp 220 ^° C (dec.). Mass spectrum (m / z):

205, 203 (M &lt; + &gt;).

For

C ₄ H ₂ N ₃ SBr.l / 2H ₂ O calculated: 22.55% C,

3.75% O, 15.02% S, 37.50% Br,

1.42% H, found:

19.72% N,

22.79% C,

H, 1.41; N, 19.42; S, 2.67; S, 14.61; Br, 38.20.

In a similar way, but by substituting cyanogen bromide with other halocyanates, the following compounds were produced:

3-iodoimidazo [1,2-d] -1,2,4-thiadiazole a

3-chloro-imidazo [1,2-d] -1,2,4-thiadiazole.

Example 30

Synthesis of 3-methylsulfonyl-1,2,4-thiadiazolo [4,5-a] benzimidazole

To a solution of 3-methylthio-1,2,4-thiadiazolo [4,5-a] benzimidazole (100 mg, 0.45 mmol) in 10 mL of dichloromethane was added m-chloroperbenzoic acid (287 mg, 0.95 mmol). The mixture was stirred at room temperature, converted to sulfone for 18 hours. and the residue is chromatographed with 10: 0.1 methanol.

The starting material was disulfide. Then further elution of the solvent followed by evaporation of the chloroform mixtures gave 50 mg (44%).

3-methylsulfonyl-1,2,4-thiadiazolo [4,5-a] benzimidazole in form

about.

m.p. 203-207 ° C (dec.). ^X H NMR _(CDCl3, C): 8.31 (d, 1H), 7.84 (d, 1H), 7.54 (ddd, 1H), 7.43 (td, 1H), 3.63 (s, 1 H) ppm. IR (KBr): 1530, 1487,

1444, 1324, 1315, 1193, 1147, 1141 and 735 cm ^-3 -. MS (m / z): 253 (M ^+), 174 (M ⁺ - _{CH3 SO2),} 148 (M

- CH SO CN).

2

Example 31

Synthesis of 3- [4- (2-pyridyl) piperazinyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole

To a cooled solution of 3-bromo-1,2,4-thiadiazolo [4,5-a] benzimidazole (0.30 mg, 1.17 mmol) in 10 mL of dichloromethane was added dropwise 2-pyridylpiperazine (0.54 mL, 3.51 mmol). The mixture was stirred for 16 hours. The reaction mixture was diluted with 100 mL of dichloromethane and washed with water (2 x 30 mL) and brine (1 x 25 mL). The organic layer was dried over sodium sulfate and evaporated. A yellow oil was obtained which was purified by column chromatography (elution with 40% ethyl acetate / 60% hexane). 0.27 g (68.5%) of white is obtained

solid. ^X H NMR (CDC1 _3, C): 3.58 (m, 4H, 2CH ₂ ), 3.58 (M, 4H, 2CH ₂ ), 6.75 (m, 2H, pyr-H) , 7.30 (T, 1H, ArH), 7.44 (T, 1H, ArH), 7.55 (m, 1H, pyr-H), 7.68 (D, 1H, ArH), 7.79 (D, 1H, And 8.24 (m, 1 H, pyr-H). T . t. 176 až

177,5 ^c C.

In a similar manner, but substituting 2-pyridylpiperazine for other piperazine derivatives, the following compounds were prepared:

3- [4-ethyl-piperazinyl] -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 _3, δ): 1.15 (t, 3H, CHJ, 2.55 (q , 2H,

_CH2), 2.70 (br s, 4H, ₂ CH2), 3.49 (br s, 4H, ₂ CH2), 7.25 (m, 1 H, Ar H), 7.40 (m, 1 H, Ar 7.65 (d, 1H, ArH), 7.79 (d, 1H, ArH). T. t. 153-154.5 ° C.

3- [4-propylpiperazinyl] -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 _3, d): 0.96 (t, 3H, CHJ, 1.58 (m , 2H,

CH ₂ ), 2.45 (t, 2H, CH ₂ ), 2.74 (broad s, 4H, 2CH 3, 3.49 (broad s, 4H, ₂ CH ₂ ), 7.26 (t, 1H, ArH) 7.30 (t, 1H, Ar H),

7.64 (d, 1H, ArH); 7.77 (d, 1H, ArH). T. t. 137 DEG-138 DEG C.

3- (4- (2-hydroxyethyl) piperazinyl] -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 _3, δ): 2.65 (s, 1H, OH) , 2.72 (t, 2H, _CH2), 2.84 (s, 4H, 2CHJ, 3.51 (s, 4 H, 2CHJ, 3.70 (t, 2H, _CH2), 7.31 (t 1H, ArH), 7.45 (t, 1H, ArH), 7.66 (d, 1H, ArH), 7.80 (d, 1H, ArH), mp 160-161.5 ° C .

- [4- (3-chlorophenyl) piperazinyl] -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 _3, d): 3.37 (m, 6H, 3 CH ₂₎ .

3.54 (m, 4H, _2CH), 6.88 (d, 1 H, Ar H), 7.04 (dd, 1 H, Ar H);

7.10 (broad s, 1H, ArH), 7.29 (t, 1H, ArH), 7.41 (t, 1H, ArH), 7.50 (t, 1H, ArH), 7.78 (d (1H, ArH), 7.82 (d, 1H, ArH). T. t. 218.5 to 219.5 ⁰ C.

- [4-benzylpiperazinyl] -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 _3, d): 2.76 (br s, 4H, ₂ CH2), 3.49 (broad s, 4H, 2 CH3, 3.66 (s, 2H, CH3), 7.30-7.50 (m, 8H, ArH), 7.64 (d, 1H, ArH), 7.78 ( d, 1H, ArH), mp 110-112.5 ^° C.

3- [4-cinamylpiperazinyl] -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 _3, d): 2.81 (s, 4 H, 2CHJ, 3.32 (d , 2H, _CH2), 3.51 (s, 4H, ₂ CH2), 6.27 to 6.36 (m, 1H, CH), 6.60 (d,

1H, CH), 7.23-7.46 (m, 7H, ArH), 7.65 (d, 1H, ArH), 7.79 (d, 1H, ArH). T. t. Mp 120-121.5 ° C.

3- [4- (3-amino-2-pyridyl) piperazinyl] -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 _3, d): 3.42 (m, 4H, 2CH ₂ ), 3.55 (m, 4H, ₂ CH ₂ ), 3.88 (s, 2H, NH 3, 6.92 (dd, J = 4.74 Hz, 7.69 Hz, 1H, pyr- H-4), 7.02 (dd, J = 1.57 Hz, 7.69 Hz, 1H, pyr-H-3), 7.30 (d, 1H, ArH), 7.44 (d, 1H) (ArH), 7.76 (apparent broad t, 2H, ArH), 7.86 (dd, J = 1.57 Hz, 4.78 Hz, 1H, pyr-H), mp 176-177, 5 ° C.

3- [4- (1- (4-chlorophenyl) -1-fenylmetylpiperazinyl] -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR _(CDCl3, d): 2.68 ( br s, 4H, ₂ CH2), 3.49 (br s, 4H, ₂ CH2), 4.35 (s, 1H, CH), 7.2 to 7.5 (m, 11H, Ar-H), 7, 79 (d, 1H, ArH), mp 172.5-174 ^° C.

Example 32

Synthesis of 3- [2-pyridylamino] -1,2,4-thiadiazolo [4,5-a] benzimidazole

To a cooled solution of 3-bromo-1,2,4-thiadiazolo [4,5-a] benzimidazole (0.30 mg, 1.17 mmol) in 15 mL of dichloromethane was added dropwise 2-aminopyridine (0.276 g, 93 mmol). The mixture was stirred for 48 hours. The reaction mixture was diluted with 100 mL of dichloromethane and washed with water (2 x 30 mL) and brine (1 x 25 mL). The organic layer was dried over magnesium sulfate and evaporated. Obtained as a yellow solid (0.26 g, 83%). ^X H-NMR (CDC1 _3, C): 6.59 (app s, 1H, pyr-H), 7.12 (app br d, 1H, pyr-H), 7.28 (t, 1 H, Ar-H) 7.38 (t, 1H, ArH), 7.51 (m, 2H, ArH and pyr-H), 7.70 (d, 1H, ArH), 8.28 (d, 1H, pyr-H) . T. t. 155.5-157 ° C.

In a similar manner, but substituting 2-aminopyridine with other amine derivatives, the following compounds were prepared:

3- [3-pyridylamino] -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR _(CDCl3, d): 7.41 (t, 1 H, Ar H), 7.48 ( t, 1H, ArH), 7.62 (dd, 1H, pyr-H), 7.75 (d, 1H, ArH), 8.34 (d, 1H, ArH), 8.44 (m, 2H, pyr-H), 9.02 (d, 1H, pyr-H). T. t. 175-176 ⁰ C.

3- [2-pyridylmethylamino] -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 _3, £): 2.02 (s, 1 H, NH), 4.84 ( d, 2H,

CH ₂ ), 7.22 to 7.56 (m, 4H, 2ArH and 2pyr-H), 7.75 (m, 2H, ArH and pyr-H), 7.85 (d, 1H, ArH), 8 66 (d, 1H, pyr-H). T. t. 155.5 to 157 ⁰ C.

3- [N-methyl- (2-pyridylethyl) amino] -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 _3, d): 3.11 (s, 3 H, CHJ, 3.18 (t, 2H, _CH2), 3.87 (t, 2H, CHJ, 7.04 to 7.11 (m, 2H, Pyr-H),

7.26 (m, 1H, Ar-H), 7.40 (t, 1H, Ar-H), 7.52 (m, 1H, pyr-H),

7.63 (d, 1H, ArH), 7.74 (d, 1H, ArH) and 8.41 (d, 1H pyr-H).

T. t. 105 to 107 ⁰ C.

Example 33

Synthesis of 3-bromomethyl-1,2,4-thiadiazolo [4,5-a] benzimidazole

A solution of 2-butyl-1,2,4-thiadiazolo [4,5-a] benzimidazol-3 (2H) -one (15 g, 60.5 mmol) and bromoacetonitrile (18.19 g,

151.6 mmol) in dichloromethane (150 mL) was stirred for 48 hours. A white precipitate is formed. The insoluble white material was filtered off. Thus, 12.50 g (77%) of the title compound are obtained. ^X H-NMR (CDC1 _3, d): 4.79 (s, 2H, _CH2), 7.42 (t, 1 H, Ar H), 7.51 (t, 1 H, Ar H), 7.84 (d (1H, ArH) and 7.94 (d, 1H, ArH). T. t. Mp 242-244 ° C.

Example 34

Synthesis of 3 - {[4-ethylpiperazinyl] methyl} -1,2,4-thiadiazolo [4,5-a] benzimidazole

1-Ethylpiperazine (0.732 mL, 6.03 mmol) was added to a suspension of 3-bromomethyl-1,2,4-thiadiazolo [4,5- a] benzimidazole (704 mg, 2.62 mmol) in dichloromethane (20 mL) . This mixture was allowed to stir at room temperature for 26 hours. The material was diluted with dichloromethane (150 mL) and washed with water (15 mL) and brine (15 mL). The organic layer was dried over sodium sulfate and the solvent was evaporated. A solid is obtained which is recrystallized from acetonitrile

(600 g, yield: 75.9%). ^X H-NMR (CDC1 _3, d): 1.06 (t, 3H, CH ₃ ), 2.39 (q, 2H, CH ₃ , 2.44 (M, 4H, ₂ CH2), 2.70 (M, 4H, 2CHJ, 3.90 (s, 2H, CHJ, 7.31 (T, 1H, ArH), 7.43 (T, 1H, ArH), 7.78 (d, 1H, ArH) and 7.92 (D, 1H, ArH) .T. t. 140 until

141.5 ° C.

In a similar manner, but replacing 1-ethylpiperazine piperazine derivatives, the following compounds are prepared: 3 - {[4-propylpiperazinyl] methyl} -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 ₃ , d): 0.89 (t, 3H, C H _a), 1.51 (m, 2H, _CH2), 2.30 (t, 2H, _CH2), 2.50 (br s, 4 H, 2CHJ .

2.70 (s, 4H, 2CH _z), 3.99 (s, 2H, CHJ, 7.32 (t, 1 H, Ar H);

7.45 (t, 1H, ArH), 7.80 (d, 1H, ArH) and 7.95 (d, 1H, ArH). T. t. 108 to 110 ⁰ C.

3 - {[4- (2-hydroxyethyl) piperazinyl] methyl} -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H-NMR (CDCl _a, J): 2.55 (m, 6 H .

2 CH ₂ of piperazine, CHJ, 2.70 (m, 4 H, 2CHJ, 3.61 (m, 2H, CHU,

3.99 (s, 2H, _CH2), 7.32 (t, 1 H, Ar H), 7.45 (t, 1 H, Ar H), 7.78 (d, 1 H, Ar H), 7.91 (d (1H, ArH). T. t. 165-166.5 ° C.

3 - {[4-phenylpiperazinyl] methyl} -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 _3, d): 2.80 (m, 4H, CH2 _of).

3.20 (m, 4H, 2CHJ, 4.00 (s, 2H, CHJ), 6.90 (m, 3H, ArH),

7.25 (t, 4H, ArH), 7.50 (t, 1H, ArH), 7.80 (d, 1H, ArH) and 8.00 (d, 1H, ArH). T. t. Mp 197-197.5 ° C.

3 - {[4- (4-amino) phenylpiperazinyl] methyl} -l, 2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 _3, <I '): 2.82 (m, 4H, 2CHJ, 3.00 (m, 4 H, 2CH.J, 3.31 (s, 2H, NH_J, 4.01 (s, 2H, _CH2), 6.63 (d, 2H, Ar H), 6 78 (d, 2H, ArH); 7.32 (t, 1H, ArH);

7.45 (t, 1H, ArH), 7.80 (d, 1H, ArH) and 7.98 (d, 1H, ArH). T. t. 199.5 to 200.5 ⁰ C.

3 - {[4-benzylpiperazinyl] methyl} -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 _3): 2.50 (br s, 4 H,

2CH _a ), 2.68 (broad s, 4H, 2CHJ, 3.49 (s, 2H, CHJ, 3.98 (s,

2H, _CH2), 7.30 (t, 6H, Ar H), 7.46 (t, 1 H, Ar H), 7.79 (d, 1 H,

ArH) and 7.94 (d, 1H, ArH). T. t. 120.5 to 122 ⁰ C.

3 - {[4-cinamylpiperazinyl] methyl} -1,2,4-thiadiazole [4,5-a] benz

4 · imidazole, ^X H-NMR (CDC1 _3, d): 2.71 (m, 4H, 2CH ₂₎ ), 2.55 (M, 4H, 2CH ₂ ), 3.14 (d, 2H, CH _z), 3.98 (with, 2H, CH _2), 6 , 27 (D, « 1H, CH), 6.49 (d, 1H, CH), 7.30-7.37 (M, 6H, ArH), 7 »46 (T, 1H, Ar) , 7.77 (d, 1H, ArH) and 7.93 (d, 1H, Ar) .T.t. 162 until

163 ⁰ C.

3 - {[4- (2-pyridyl) piperazinyl] methyl} -l, 2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 _3, d): 2.80 (m, 4 H , 2CH _z ),

3.60 (m, 4H, 2CHJ), 4.00 (s, 2H, CHJ, 6.60 (m, 2H, pyr-H),

7.31 (t, 1H, ArH), 7.45 (t, 2H, ArH), 7.80 (d, 1H, ArH), 7.98 (d, 1H, pyr-H) and 8.18 ( m, 1H, pyr-H). T. t. Mp 214-214.5 ° C.

3 - {[4- (3-amino-2-pyridyl) piperazinyl] methyl} -1,2,4-tiadiazolo69 [4,5-a] ^{benzimidazole;} H NMR _(CDCl3, d): 2.82 (broad s, 4H, 2CH), 3.17 (broad s, 4H, 2CH), 3.79 (s, 2H, NH),

4.07 (s, 1H, CH ₌ ), 6.84 (m, 1H, pyr-H), 6.94 (m, 1H, pyr-H), 7.30 (m, 1H, ArH), 7 50 (m, 1H, ArH), 7.79 (m, 2H, pyr-H, ArH) and 8.0 (d, 1H, ArH). T. t. 214-215.5 ° C.

3 - {[4- (4-methoxyphenyl) piperazinyl] methyl} -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR _(CDCl3, d): 2.80 (m, 4 H , _2CH), 3.10 (m, 4H, ₂ CH2), 3.80 (s, 3H, OCH, 4.10 (s, 2H, _CH2), 6.80 (m, 4H, Ar H); 7.30 (t, 1H, ArH); 7.50 (t, 1H, ArH);

7.80 (d, 1H, ArH) and 8.00 (d, 1H, ArH). T. t. 202-204.5 C.

3 - {[4- (1- (4-chlorophenyl) -1-phenylmethyl) piperazinyl] methyl} -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 _3, J): 2.44 (br s, 4H, ₂ CH2), 2.68 (br s, 4H, ₂ CH2), 3.99 (s, 2H, _CH2), 4.18 (s, 1H, CH), 7 20 to 7.40 (m, 10H, ArH), 7.50 (t, 1H, ArH), 7.79 (d, 1H, ArH) and 7.91 (d, 1H,

ArH). T. t. 82 to 84 ⁰ C.

Example 35

Synthesis of 3-dipropylaminomethyl-1,2,4-thiadiazolo [4,5-a] benzimidazole

Dipropylamine (0.64 mL, 4.67 mmol) was added to a suspension of 3-bromomethyl-1,2,4-thiadiazolo [4,5- a] benzimidazole (0.5 g, 1.87 mmol) in dichloromethane (40 mL). ml). This mixture was allowed to stir at room temperature for 26 hours. The material was diluted with dichloromethane (100 mL) and washed with water (3 x 40 mL) and 10% sodium sulfate (15 mL). The organic layer was dried over magnesium sulfate and evaporated. There was thus obtained a solid which was recrystallized from acetonitrile (370 mg, yield: 69%). ^X H-NMR (CDC1 _3, d): 0.82 (t, 6H, 2CHJ, 1.50 (m, 4 H, 2CHJ,

2.60 (m, 4H, 2CH ₂ ), 4.11 (s, 2H, CH ₃ ), 7.31 (t, 1 H, ArH), 7.44 (t, 1 H, ArH), 7.78 (d, 1H, ArH) and 8.03 (d, 1H, ArH), mp 70.5-72.5 ^° C.

ΊΟ

In a similar manner, but substituting dipropylamine for other amine derivatives, the following compounds were prepared: 3-dimethylaminomethyl-1,2,4-thiadiazolo [4,5- a] benzimidazole, 1 H NMR (CDCl ₃ , d): 2.41 (s) , 6 H, 2CHJ, 3.90 (s, 2H, _CH2), 7.32 (t, 1 H, Ar H), 7.44 (t, 1 H, Ar H), 7.76 (d, 1 H, Ar H), and 7.99 (d, 1H, ArH), mp 134-135.5 ° C.

3-diethylaminomethyl-l, 2,4-thiadiazole [4,5-a] benzimidazole,

^X H NMR (CDC1 _3, C): 1.07 (t, 6H, 2CH ₃ ), 2.73 (q, 4H, 2CH ₂ ), 4.08 (s, 2H, CH _z), 7.30 (M, 1H, ArH), 7.43 (M, 1H, ArH), 7.77 (d, 1H, ArH) and 8.04 (D, 1H, ArH). T. t. 109 until

110.5 ⁰ C.

3-dibutylaminomethyl-l, 2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 _3, d): 0.85 (m, 6H, 2CHJ, 1.26 (m, 4H, 2CH ₂ ), 1.43 (m, 4H, 2 CH 3, 2.65 (m, 4H, ₂ CH ₃ , 4.10 (s, 2H, CH ₂ )), 7.27 (t, 1H, Ar H), 7.45 ( t, 1H, ArH), 7.78 (d, 1H ArH) and 8.02 (d, 1H, ArH), mp 72-72.5 ° C.

3- (morpholinomethyl) -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 _3, C): 2.66 (m, 4 H, 2CHJ, 3.71 (m, 4 H 2CH ₂ ), 3.99 (s, 2H, CH ₃ ), 7.33 (t, 1 H, ArH), 7.45 (t, 1 H, ArH), 7.80 (d, 1 H, ArH) and 7, 91 (d, 1H, ArH), m.p.

147 ⁰ C.

3- (imidazolylmethyl) -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR _(CDCl3, d): 6.35 (s, 2H, CHJ, 7.48 (t, 1 H .

ArH), 7.54 (t, 1H, ArH), 7.72 (d, 1H, ArH), 7.84 (m, 1H, ArH, Ind-H), 8.14 (d, 1H, ArH) and 9.12 (d, 1H, ArH). T. t. 226-227 ^° C.

3- (1,2,4-triazolylmethyl) -1,2,4-thiadiazole [4,5-a] ^{benzimidazole;} H NMR (CDC1 _3, <T): 6.26 (s, 2H, CHU, 7.39 (t, 1 H,

ArH), 7.50 (t, 1H, ArH), 7.80 (d, 1H, ArH), 8.04 (d, 1H, ArH), 8.10 (s, 1H, H triazole) and 8, 83 (s, 1H, H of the triazole). T. t.

204.5 to 206 ⁰ C.

Example 36

Synthesis of 3- (2-pyrazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole

A mixture of 2-butyl-1,2,4-thiadiazolo [4,5-a] benzimidazol-3 (2H) -one (300 mg, 1.213 mmol) and pyrazinecarbonitrile (319 mg, 3.03 mmol) in 8 mL of dichloromethane was added. Stir for 36 hours at room temperature. The precipitate was filtered off and washed with dichloromethane. There was thus obtained 3- (2-pyrazinyl) -1,2,4-thiadiazolo [4,5- a] benzimidazole (0.28 g, 91%) as a white solid. ^X H NMR _(CDCl3, d): 7.32 (t, 1 H, Ar H), 7.50 (t, • 1 H, Ar H), 7.83 (d, 1 H, Ar H), 8.67 (d 1H, ArH), 8.87 (broad d, 2H, py-H), 9.59 (S, 1H, py-H). T. t. 255-256.5 ° C.

Example 37

Synthesis of 4- (2-pyridyl) piperazinylcarbonyl-1,2,4-thiadiazolo [4,5-a] benzimidazole

1,1-Carbonyldiimidazole (0.355 g, 2.19 mmol) was added to a solution of 2-carboxy-1,2,4-thiadiazolo [4,5-a] benzimidazole (0.3 g, 1.37 mmol) in dimethylformamide (10 mL). The resulting solution was stirred at 40 ° C for 2 hours. The reaction mixture gradually changed from a white suspension to a yellow solution. N- (2-pyridyl) piperazine (0.268 g, 1.64 mmol) was added to the reaction mixture.

* ·

The resulting mixture was stirred at 40 ° C for 3 hours and then cooled. _t This material was diluted with dichloromethane (100 mL), washed with 1N KC1 (40 ml) then 5% NaOH (60 mL). The organic layer was dried over magnesium sulfate and the solvent was evaporated. There was thus obtained the title compound as a solid (0.2 g, yield: 40%). ^X H NMR _(CDCl3, C): 3.69 (m, 2H, _CH2), 3.79 (m, 2H, CHJ, 4.05 (m, 4 H, 2CHJ, 6.70 (m, 2H , pyr-H), 7.30 (t, 1H, ArH), 7.40 to 7.60 (m, 2H, ArH and pyr-H),

7.80 (d, 1H, ArH), 8.00 (d, 1H, ArH) and 8.23 (m, 1H, pyr-H) ppm. T. t. Mp 222-223.5 ° C.

In a similar way, but substituting 4- (2-pyridyl) piperazine for other amine derivatives, the following compounds were prepared: 3- {4- (benzyl) piperazinylcarbonyl} -1,2,4-thiadiazolo [4,5-a] benzimidazole, ^X 1 H NMR Spectrum (CDCl ₃ , d): 2.72 (m, 4H, 2CHJ,

3.60 (s, 2H, _CH2), 3.92 (m, 4H, ₂ CH2), 7.31 (t, 7 H, Ar H);

7.46 (t, 1H, ArH), 7.80 (d, 1H, ArH) and 7.98 (d, 1H, ArH) ppm. T. t. 230.5 to 231.5 ⁰ C.

3- {4-metylpiperazinylkarbonyl} -1,2,4-thiadiazole [4,5-a] benzimidazole, ^{Χ Η} NMR (CDC1 _3, d): 2.37 (s, 3H, _CH3), 2.51 (t, 2H, _CH2), 2.60 (t, 2H, CHJ, 3.90 (t, 2H, CHJ, 3.96 (t, 2H, _CH2), 7.33 (t, 1 H, Ar H 7.73 (t, 1H, ArH), 7.80 (d, 1H, * ArH) and 7.98 (d, 1H, ArH) ppm.

Example 38

Synthesis of 3- (4-butylpiperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole

A mixture of potassium carbonate (700 mg, 5.06 mmol), butyl bromide (0.43 mL, 0.4 mmol) and 3-piperazinyl-1,2,4-thiadiazolo [4,5-a] benzimidazole (798 mg, 3 1.0 mmol) in tetrahydrofuran (15 mL) and DMSO (2 mL) was heated at reflux for 16 h. This solution was evaporated to dryness. The residue was partitioned between dichloromethane and water. The organic layer was washed five times with water, dried over sodium sulfate and evaporated. An oil is obtained. This oil was treated with acetonitrile and the insoluble solid formed was filtered off (595 mg). This solid was purified by chromatography. There was thus obtained the title compound which was recrystallized from hexane (5:95) (440 g, 41%). ^X H-NMR (CDC1 _3, (T): 0.95 (t, 3H, CHJ, 1.30 (m, 2H, CH), 1.50 (m, 2H, CH), 2.40 (t, 2H, CH), 2.7 (m, 4H, 2CHJ), 3.5 (m, 4H, 2CHJ, 7.3 (t, 1H, ArH), 7.4 (t, 1H, ArH), 7.65 (d, 1H, ArH) and 7.8 (d, 1H, ArH) ppm, mp 121-122.5 ^° C.

Example 39

Synthesis of 2-mercapto-5- (tert-butoxycarbonyl) aminobenzimidazole

A. A mixture of 2-mercapto-5-nitrobenzimidazole (10.0 g, 51.23 mmol) and iron filings (8.0 g, 143.24 mmol) in ethanol (80 mL) and water (10 mL) was boiled under reflux condenser. Concentrated HCl (1.2 mL) was then added dropwise over about 12 minutes. The resulting dark brown mixture was refluxed for an additional 1.5 hours. It is then cooled in ice. The reaction mixture was neutralized with saturated sodium bicarbonate solution to pH 7.0. The mixture was diluted with ethanol (50 mL), treated with celite (0.82 g) to a suspension and filtered through a pad of celite. The cake was washed with ethanol (3 x 100 mL). The combined filtrate was concentrated in vacuo. There was obtained 9.2 g of a pale brown solid. Crystallization from hot water gave 2-mercapto-5-aminobenzimidazole (6.74 g, 80%) as a pale brown solid. ^X H NMR (DMSO, d): 4.98 (br s, 2H);

6.40 to 6.43 (m, 2H, ArH),

ArH), 12.06 (broad s, 1H)

165.9 (CS), 144.9, 133.4,

6.81 to 6.85 (d, J = 9.0 Hz, 1H, ppm. ¹³ C NMR spectrum (DMSO, δ): 123.6, 109.8, 94.4. IR spectrum (KBr, cm) - ¹ ): 3362, 3295, 3173, 1637, 1622 and 1507.

B. A solution of 2-mercapto-5-aminobenzimidazole (22.0 g, 133.2 mmol) and di (tert-butyl) dicarbonate (30.52 g, 139.86 mmol) in anhydrous tetrahydrofuran (200 mL) was stirred for 16 min. hours at room temperature under a nitrogen atmosphere.

THF was removed by evaporation under reduced pressure. The residue was recrystallized from acetonitrile. There was thus obtained the title compound (28.7 g, 80%) as a pale yellow solid. ³ H NMR Spectrum (DMSO, d 6): 1.50 (s, 9H), 7.00 (d, J = 8.6 Hz, 1H, Ar-H), 7.11 (dd, J = 8.6) and 1.8 Hz, 1H, Ar-H), 7.53 (s, 1H, Ar-H), 9.41 (broad s, 1H), 12.41 (broad s, 2H). ¹³ C NMR spectrum (DMSO, d 6): 167.9 (CS), 152.9 (C = O), 134.9, 132.5,

127.5, 113.3, 109.3, 99.5. 79.0 (C-O) and 28.2. Company ID (KBr) 3300 3127 1724 1706 1623 and 1530. - calculated: 54.32 % c, 5.70% H, 15.84% N, 54.32% C, 5 71% H, 15.85 % N.

spectrum

Analysis found:

Example 40

Synthesis of 5 '- (tert-butoxycarbonyl) amino-2-butyl-3-oxo-2,3-dihydro-1,2,4-thiadiazolo [4,5-a] benzimidazole and 6 ^1- (tert-butoxycarbonyl) amino 2-butyl-3-oxo-2,3-dihydro-l, 2,4-thiadiazole [4,5-a] benzimidazole

A. To a suspension of 2-mercapto-5- (tert-butoxycarbonyl) aminobenzimidazole (11.46 g, 43.19 mmol) in o-xylene (50 mL), pre-heated to 100 ^° C, was added butyl isocyanate by syringe. (7.3 mL, 64.78 mmol). The mixture is then heated

1.5 hours at 145-150 ⁰ C, then cooled to room temperature and diluted with hexane (200 mL). The solid was collected by filtration and dried in vacuo. There was thus obtained 1-butylcarbonyl-2-mercapto-5- (tert-butoxycarbonyl) amino-benzimidazole (14.19 g, 95%). ^X H NMR (DMSO, d): 0.94 (t, J = 7.2 Hz, 3H), 1.20 1.60 (m, 4 H, 2CHJ, 1.51 (s, 9H);

3.37 to 3.43 (m, 2H, CH-N), 7.19 to 7.23 (dd, J = 9.0 and 1.9 Hz, 1H, Ar-H), 7.64 ( s, 1H), 7.96 (d, J = 9.0 Hz, 1H, Ar-H), 9.59 (s, 1H), 10.22 (t, J = 5.4 Hz, 1H, NHCH) ^). Analysis - Calculated: C 56.0%, H 6.6%, N 15.4%, Found: C 55.8%, H 5.7%, N 15.3%.

B. A suspension of 1-butylcarbamoyl-2-mercapto-5- (tert-butoxycarbonyl) amino-benzimidazole (12.90 g, 34.50 mmol) in chloroform (50 mL) was cooled to -5 ° C. charge of triethylamine (9.9 ml, 70.79 mmol). The resulting clear solution was stirred at 0 ° C for 45 minutes. Bromine (1.82 mL, 35.4 mmol) in chloroform (40 mL) was then added dropwise over about 1.5 hours.

After stirring an additional 15 minutes at 0 ° C, the mixture was allowed to warm to room temperature and then diluted with chloroform (1.25 L). The organic phase was washed with brine (2 x 100 mL), dried over sodium sulfate, filtered and concentrated in vacuo. The residue was slurried in methanol (100 mL) and filtered. The off-white solid was collected and dried under vacuum. Gives the title compounds as a mixture of 85:15 (by ^X H NMR).

The proton NMR spectra obtained by heating the samples helped to assign the maxima in the aromatic region corresponding to the two isomers.

Isomer 1: ^X H NMR (DMSO, C): 0.95 (t, J = 7.2 Hz, 3H), 1.36 to 1.43 (q, J = 6.8 Hz, 2H, CH N), 1.53 (s, 3H), 1.65-1.73 (m, 2H, CH 3), 3.73-3.78 (t, J = 6.8 Hz, 2H, CH 2 N), 7.38 (d, J = 8.7 Hz, 1H, Ar-H), 7.80 (d, J = 8.6 Hz, 1H, Ar-H), 7.98 (s, 1H, Ar- H), 9.53 (s, 1H).

Isomer 2: ^X H NMR (DMSO, C): 0.95 (t, J = 7.2 Hz,

3H), 1.36 to 1.43 (q, J = 7.4 Hz, 2 H, CH ₂ CH _3), 1.53 (s, 3H), 1.65 to 1.73 (m, 2H, CHJ , 3.73 to 3.78 (t, J = 6.8 Hz, 2H, _CH2 N), 7.38 (d, J = 8.7 Hz, 1H, Ar-H), 7.63 (d J = 8.6 Hz, 1H, Ar-H), 8.34 (s, 1H, Ar-H), 9.60 (s, 1H).

Example 41

Synthesis of 5'-amino- [3- (2-pyridyl)] - 1,2,4-thiadiazolo [4,5-a] benzimidazole and 6'-amino- [3- (2-pyridyl)] - 1,2 , 4-thiadiazole [4,5-] benzimidazole

A. To a suspension of the products of Part B of Example 40 (1.0 g, 2.76 mmol) in chloroform (5.0 mL) was added all 2-cyanopyridine (0.575 g, 5.52 mmol) in one portion. The resulting mixture was refluxed for 5 hours. It is then stirred for 16 hours at room temperature.

The chloroform was removed under reduced pressure. The residue was triturated with diethyl ether (10 mL) to a suspension and the suspension was filtered. An off-white solid is isolated and dried under vacuum. There was thus obtained 0.68 g (67%) of 5 ^1- (tert-butoxycarbonyl) amino- [3- (2-pyridyl)] - 1,2,4-thiadiazolo [4,5-a] benzimidazole and 6 ¹ - (tert-butoxycarbonyl) amino- [3- (2-pyridyl)] 1,2,4-thiadiazolo [4,5- a] benzimidazole in a ratio of about 1: 1.

^X H NMR _(CDCl3, C): 1.56 (s, 9 H), 6.67 (br s,

1 H, NH), 7.23-7.32 (m, 1H, py-H), 7.54-7.60 (m, 1H,

Ar-H), 7.66 to 7.69 (d, J = 8.7 Hz, 0.5H, Ar-H), 7.79 (d, J = 1.9 Hz, 0.5H, Ar- H), 7.93-7.98 (t, J = 8.0 Hz, 1H, py-H), 8.28-8.32 (m, 1H, py-H), 8.64 (d, J = 9.0 Hz, 0.5H, Ar-H), 8.86 to 8.89 (dd, J = 4.8 and 0.9 Hz, 0.5H, py-H), 8.98 ( broad d, J = 4.8 Hz, 0.5H, py-H) and 9.20 (broad s, 0.5H).

B. A suspension of the compounds obtained in Part A of Example 41 (1.0 g, 2.72 mmol) in a solution of HCl in methanol (25 mL) was stirred

4.5 hours at room temperature. An additional 25 mL of HCl in methanol was added and the volatiles were removed in vacuo. The residue is slurried with diethyl ether. Filtration gave the title compounds as a pale yellow hydrochloride salt (0.99 g, 96.6%) in an approximately 1: 1 mixture of isomers (HPLC: 20 mM ammonium acetate / acetonitrile, 80/20, C18 column). Mass spectrum (KBr): 3419, 1611, 1551 and 1527 cm ^-1

- calculated: 41.5% C, 3.2% H, 18.6% N, found: 41.0% C,

3.5% H, 18.3% N.

Example 42

Synthesis of 1,2,4-thiadiazolo [4,5-a] benzimidazol-3-yl-L-leucyl-isoamylamide

Potassium carbonate (544 mg, 3.94 mmol) was added to a solution of L-leucyl-isoamylamide (0.788 g, 3.94 mmol) and 3-bromo-1,2,4-thiadiazolo [4,5-a] benzimidazole ( 1.0 g, 3.94 mmol) in tetrahydrofuran (15 mL). The mixture was stirred at room temperature for 16 hours and then refluxed for an additional 8 hours. The solvent was evaporated to dryness. The residue was partitioned between ethyl acetate (125 mL) and water (15 mL). The organic phase is washed with brine (10 ml), dried over sodium sulphate and evaporated. A solid was obtained which was further purified by column chromatography (10% methanol with chloroform). There was thus obtained 715 mg of the title compound. ^X H-NMR (CDCl _a, d): 0.92 (d, 6H, _2CH), 0.92 1.10 (dd, 6H, 2CH _3), 1.40 to 1.52 (m, 2H ), 1.54 to 1.78 (m,

2Η), 1.80 to 2.00 (m, 2H, CH 3), 3.34 to 3.45 (m, 2H, CH 2 NH),

4.48 to 4.58 (m, 1H, -CH from Leu), 6.56 (t, J = 5.6 Hz, 1H,

NHCH3, 6.60 (d, J = 8.3 Hz, 1H, NHCH), 7.15 (t, J = 7.4 Hz,

1 H, Ar-H), 7.34 (t, 1 H, J = 8.2 Hz, Ar-H), 7.64 (d, 1 H, J =

8.2 Hz, Ar-H), 7.77 (d, 1H, J = 8.1 Hz, Ar-H). ¹³ C NMR (CDCl ₃ , d): 172.5 (CO-NH), 164.4 (CS), 150.4,

145.0, 127.8, 124.5, 121.3, 119.1, 110.2, 55.4 (CH-CO), 41.7,

38.4, 38.2, 25.8, 24.9, 23.0, 22.4 and 22.1. IR (thin film): 3241 (NH), 1660 (C = O), and 1574 cm ^{@ -1} . T. t. 105 až

H, 7.29; N, 18.75. Found: C, 61.30; H, 7.05; N, 18.43.

Example 43

Synthesis of {1,2,4-thiadiazolo [4,5-a] benzimidazol-3-yl} -carbonyl-L-leucyl-isoamylamide

1,1-Carbonyldiimidazole (1.30 g, 8.03 mmol) was added to a suspension of 3-carboxy-1,2,4-thiadiazolo [4,5-a] benzimidazole (1.10 g, 5.02 mmol) in dimethylformamide (DMF; 30 mL). The mixture was heated at 45 ° C for two hours. During this time, the mixture turned to a yellow solution. This solution was cooled to 0 ° C, leucylisoamylamide (1.21 g, 6.02 mmol) and DMF (5 mL) were added. The resulting mixture was stirred at room temperature for 16 hours. The mixture was diluted with ether (400 mL), and the ether layer was washed with 0.5 M HCl (25 mL), water (3 x 25 mL), and brine (925 mL). The ether layer was dried over sodium sulfate and the solvent was evaporated. A solid (1.77 g) was obtained, which was further purified by column chromatography. Thus 1.33 g of the desired material are obtained. ¹ H NMR Spectrum (CDCl 3, d 6): 0.90 (d, 6H, J = 6.5 Hz, 2CH 3), 1.05 (dd, 6H, 2 CH 3), 1.38-1.48 (m, 2H) 1.54-1.68 (m, 1H), 1.72-1.85 (m, 3H), 3.22-3.38 (m, 2H, CH.NH), 4.62-4. 78 (m, 1H, CHCO), 6.30 (t, 1H, NH), 7.32 (d, J = 7.3Hz, 1H, Ar-H), 7.45 (t, J = 7, 4 Hz, 1H, Ar-H), 7.75 (d, 1H, J = 8.0 Hz, Ar-H), 7.93 (d, 1H, J = 8.4 Hz, Ar-H), 8.73 (d, 1H, J = 8.3 Hz, NH) ¹³ C NMR spectrum (CDCl 3, d): 170.8 (COCH), 164.4 (CS), 155.4, 150.5, 144.1.

124.9, 125.8, 122.2, 119.1, 116.3 52.6 (CHCO), 41.4, 38.3,

38.2, 25.8, 24.9, 22.9, 22.4 and 22.1. IR (KBr): 3295 (NH), 1651 (C = O), and 1574 cm @ ^-1 . T. t. 164-167 ⁰ C.

Example 44

Synthesis of 5-amino-3-methoxy-1,2,4-thiadiazole

This material is prepared according to the method of J. Goeredeler et al., Chem. Ber. 1995, 88, 843. Cyanamide (5.77 g,

13.78 mole) was added slowly to a solution of HCl (5.77 g) in methanol (100 mL). The resulting mixture was stirred at room temperature for 3 days. The residue was evaporated under reduced pressure. There was thus obtained methylisourea hydrochloride (15.16 g). To a solution of methylisourea hydrochloride (12.63 g, 0.114 mmol) in water (75 mL) was added dropwise a solution of sodium hypochlorite (0.769M, 149 mL) at 0 ^° C over 30 min. After 1.5 h, the solution was saturated with chloride NaHCO 3 and extracted with ether (3 x 700 mL). The combined ether layer was dried over sodium sulfate. Evaporation gave N-chloromethylisourea (10.26 g, 83% yield). To a solution of N-chloroisourea (10.26 g,

94.5 mmol) in methanol (200 mL) was added KSCN (9.19 g,

94.5 mmol). After 16 hours, the insoluble residue was filtered off and washed with methanol. The combined filtrate was evaporated. This gave a solid which was purified by column chromatography (gradient elution: 5-7% methanol with chloroform). The isolated solid was recrystallized from toluene. There was thus obtained the title compound (3.14 g).

Example 45

Synthesis of 5- {3-methoxy-1,2,4-thiadiazolyl] carbamoylisoleucylisoamylamide

A solution of 5-amino-3-methoxy-1,2,4-thiadiazole (1.0 g,

7.67 mmol) in THF (20 mL) was added dropwise to a solution of triphosgene (0.837 g, 2.82 mmol) and dipropylamine (1.08 g, 8.35 mmol) at

7.62 mmol) in dichloromethane (15 mL) was removed. the material is stirred for 1 hour at room temperature with a solution of leucyl isoamylamide

After 2 hours, ° C. The resulting solution was temperature. Over 15 minutes (1/53 g, solvent under reduced pressure with ethyl acetate (500 mL), ammonium sulfate (10%, (50 mL)) was added.

This ml) and the solution were dried over Na 2 SO 4

Dilute the residue with sodium chloride solution (dd, Leu, 4.10)

6H, CH

J =

1 H, Spectrum (CS), 153.9 38.0, 25.8, 3359 (NH), 172 ^° C.

which is purified by chromatography with chloroform). To obtain (469 mg, (CDCl _a, d): 0.86 (d, 6H, J

2 CH _3), 1.34 (m, 2H), 1.53 to:

isoamyl group), 3.17 i

3H, _OCH3), 6.58 (t, 1 H, J =?

8.6 Hz, NHCH), 12.6 (broad (CDCl3, (f): 178.1)

56.6

22.4.

1680, the oil, methanol in the title ₃ , a):

(N-CO-N)

24.7, 22.8,

1701 (C = O),

Yield 17%). ^X H-NMR = 6.55 Hz,

1.73 (m, 4H, _CH2 of up to 3.33 (m,

5.4 Hz, NHCH _2), 's, 1H, NHCO).

(C-OCH ₃ ), 171.7 (CH-C = O), (CH ₃ O), 52.7 (CH-O), 41.9,

22.3 and 22.2. IR spectrum

1645 and 1554 cm ^x . T. t.

2CH _a ), 0.93

2H, _CH2 NH);

6.70 (d, ¹³ C NMR)

166.0

38.2, (KBr): 169 to

Example 46

Synthesis of 5- {benzyloxycarbonyl-L-phenylalanyl-L-alaninido} -3-methoxy-1,2,4-thiadiazole

At 0 ^° C, EDCI (300 mg, 1.62 mmol) was added to a solution of HOBt (131 mg, 0.97 mmol) and carbobenzyloxy-L-phenylalanyl-L-alanine (300 mg, 0.81 mmol) in DMF ( 2 ml). After 25 minutes, 5-amino-3-methoxy-1,2,4-thiadiazole (140 mg, 1.05 mmol) was added and the solution was stirred at room temperature for 2 days. The material was evaporated to dryness and extracted with ethyl acetate. The organic layer was dried over sodium sulfate and evaporated. An oil is obtained which is chromatographed (10% methanol with dichloromethane). 90 mg of solid material are obtained. This solid was further purified by silica gel thick layer chromatography (5% methanol with dichloromethane). There was thus obtained 30 mg of the title compound. ^X H NMR (MeOD, S): 1.42 (d, 3H, _CH3), 2.80 2.95 (dd, 1 H, _CH2 Ph), 3.08 to 3.18 (dd, 1H, CH ₂ phenyl), 3.99 (s, 3H, CH 2 O), 4.45 (dd, 1H, o-CH phenyl), 4.58 (q, 1H, -CH ala), 5.05 (s, 2H, OCH ₂ ), 7.10 to 7.40 (m, 10H, Ar-H. ¹³ C NMR spectrum (MeOD, d '): 177.3 (COCH 3, 174.4 (CO)) , 174.2 (CO), 169.5 (CS)

158.3 (CO ₂ ), 138.2, 138.1, 130.4, 129.4, 128.9, 128.8, 128.7,

127.8, 127.7, 67.7 (OCH 3), 57.6 (CHCH ₃ ), 57.1 (CH ₃ O), 39.0 (CH ₂ CH), 17.2 (CH _and CH) ).

Example 47

Synthesis of N- [3- (4-methyl-piperazinyl) - [1,2,4] thiadiazol-5-yl] -N-phenyl-benzamidine

5-Cyanimino-4,5-dihydro-3,4-diphenyl-1,2,4-diphenyl-1,2,4-thiadiazole was prepared according to the procedure of H. Sonnenschein et al., Liebigs Ann. Chem. 1992, 287-289. 1-Methylpiperazine (0.152 mL, 1.375 mmol) was added to a solution of 5-cyanimino-4,5-dihydro-3,4-diphenyl-1,2,4-thiadiazole (153 mg, 0.55 mmol) in dioxane (3 mL). The mixture was stirred at room temperature for 3 days. TLC (35% ethyl acetate with hexane) indicated the reaction was complete. The white solid formed is filtered off and then recrystallized from a 1: 9 mixture of dichloromethane and hexane. This afforded 97 mg of the title compound which was further purified by column chromatography (10% methanol with dichloromethane). ^{Χ Η} NMR (CDC1 _3, C) 2.3 (s, 3 H,

OMe), 2.4 (m, 4H, 2CHJ, 3.5 (m, 4H, 2CHJ), 7.15 to 7.25 (m,

10H, Ar-H), 8.51 (s, 1H, NH). T. t. 152.5-152.7 ° C.

Example 48

Acidic stability of 7-methoxy-3 - [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole

To monitor the stability of the title compound in an acidic medium, it is dissolved in a minimum amount of methanol. The resulting solution was added to a six molar hydrochloric acid solution. This compound was found to be very stable in acid. After 48 hours of stirring at room temperature, it was completely regenerated. In contrast, omeprazole underwent complete decomposition under the same conditions in a few minutes · 1,2,4-Thiadiazole derivatives as a direct thiol scavenger are better than omeprazole in an acidic environment because they are still acidic.

Example 49

Reaction of 3 - [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole with 3-mercaptopropionic acid

To a suspension of 250 mg of 3 - [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole in 125 ml of methanol and 38 ml of 0.1M hydrochloric acid is added 161 .mu.l of 3-mercaptopropionic acid. After complete degradation of the starting material, the mixture was neutralized to pH 6 with aqueous sodium bicarbonate and extracted with ethyl acetate. The ethyl acetate was dried over anhydrous magnesium sulfate and evaporated. The crude material is purified by chromatography. 93 mg of 2-imino-2- (2-mercapto-1-benzimidazolyl) -1- (4-methoxy-3,5-dimethyl-2-pyridyl) ethanone, 65 mg of 2-mercaptobenzimidazole and 61 mg of methyl ester 2 are obtained. - (4-methoxy-3,5-dimethyl-2-pyridyl) -2-oxoacetic acid. 2-imino-2- (2-mercapto-l-benzimidazolyl) -1- (4-methoxy-3,5-dimethyl-2-pyridyl) ethanone: ^X H NMR _(CDCl3, d): 10.55 ( broad s, 1H, NH or SH), 10.35 (broad S, 1H, NH or SH), 8.10 (d, 1H J = 7 Hz, ArH), 7.80 (s, 1H, H6 of the pyridyl group) 7.35-7.20 (m, 2H, 2 * ArH), 7.10 (d, 1H, J = 7.9 Hz, ArH), 3.75 (s, 3H, OCH3, 2.60) (s, 3H,

ArCH _a ), 2.15 (s, 3H, ArCH ₃ ) ppm. IR (KBr): 3262,

1691, 1635, 1502, 1458, 1396, 1328, 1272, 1247, 1004, and 746 cm ^-1 . Mass spectrum (electrospray, m / z): 341 (MH +), 191 (MH + - 2-mercaptobenzimidazole). 2-Mercaptobenzimidazole: this material was found to be identical to an authentic sample obtained from Aldrich Chemical Co. (by ³ Η NMR, by IR and TLC). Methyl 2- (4-methoxy-3,5-dimethyl-2-pyridyl) -2-oxoacetate: ^X H NMR (CDC1 _3, (T): 8.45 (s, 1 H, Ar H), 4.1 (s, 3H, OCHJ, 3.85 (s, 3H, OCHJ,

2.65 (s, 3 H, Ar _3), 2.4 (s, 3H, Ar ₃₎ ppm. IR (KBr): 1747, 1703, 1468, 1394, 1310, 1242, 1206, 1120, 1004, and 740 cm ^{@ -1} . Mass spectrum (m / z): 224 (M &lt; + &gt; + H), 164 (M &lt; + &gt;)

- COOMe), 136 (M * -COOMe-CO).

Example 50

Reaction of 3- (dimethylamino) -1,2,4-thiadiazolo [4,5-a] benzimidazole with phenethylmercaptan

To a solution of 23 mg of 3- (dimethylamino) -1,2,4-thiadiazolo [4,5-a] benzimidazole in 10 ml of methanol was added 360 µl of phenethyl mercaptan. After one minute the reaction is complete. The solvent was evaporated and the crude product was purified by chromatography. To give 15 mg of N ^x, N ^{x-dimethyl-2-mercapto-l-benzimidazolylamidínu: X} H NMR (DMSO-d _e, C): 7.3 to 7.0 (m, 4H, 4 x Ar H); 3.35 (br s, 2H, NH, SH), 2.88 (s, 6H, 2 x NCH ppm. IR (KBr): 3210, 1641, 1475, 1452, 1407 and 1319 cm ^"3 -.

Mass spectrum (m / z): 220 (M +), 150 (M + - Me _and NC = NH).

Example 51

Reaction of 3-bromo-1,2,4-thiadiazolo [4,5-a] benzimidazole with phenethylmercaptan

To a suspension of 500 mg of 3-bromo-1,2,4-thiadiazolo [4,5-a] benzimidazole in 50 ml of methanol was added 790 µl of phenethyl mercaptan. The solid dissolved immediately. After completion of the reaction, the solvent was evaporated and the residue was purified by chromatography. 296 mg of 2-mercapto-1-benzimidazolecarbonitrile are obtained. ^X H-NMR (DMSO-d _6, they): 12.85 (br s, 1 H, SH), 7.5 to 7.2 (m, 4 H, 4 x Ar-H) ppm. IR (KBr): 2259, 1509, 1459, 1303, 1189 and 752 cm @ ^-1 . Mass spectrum (m / z): 175 (M);

150 (* - CN).

Example 52

Reaction of 3-methoxy-1,2,4-thiadiazolo [4,5-a] benzimidazole with phenethylmercaptan

To a solution of 23 mg of 3-methoxy-1,2,4-thiadiazolo [4,5-a] benzimidazole in 10 ml of methanol was added 376 µl of phenethyl mercaptan. After one minute the reaction is complete. Methyl 2-mercapto-1-benzimidazolecarboximidate was identified as the main product of this reaction. ^X H-NMR (DMSO-d _e, C); 13.45 (wide s,

1H, SH or OH), 9.8 (s, 1H, NH or SH), 7.7 (d, 1H, J = 8Hz, ArH), 7.35-7.2 (m, 3H, 3x) ArH) 3.95 (s, 3H, OCH3 ppm. IR spectrum (KBr): 3437, 3095, 1679, 1450, 1440, 1376, 1193, and 735 cm ^-1 . Mass spectrum (m / z): 207 (M +). ), 150 (M @ + - MeOC = NH).

Example 53

Reaction of 3- (oxophenylmethyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole with phenethylmercaptan

To a suspension of 26 mg of 3- (oxophenylmethyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole in 10 ml of methanol was added 31 .mu.l of phenethyl mercaptan. Comparing 2-mercaptobenzimidazole to an authentic sample obtained from Aldrich Chemical Co. the substrate was found to undergo complete conversion to 2-mercaptobenzimidazole.

Example 54

Reaction of 3- [hydroxy (4-methoxy-3,5-dimethyl-2-pyridyl) methyl)] - 1,2,4-thiadiazolo [4,5-a] benzimidazole with phenethyl mercaptan

To a suspension of 25 mg of 3- [hydroxy (4-methoxy-3,5-dimethyl-2-pyridyl) methyl)] - 1,2,4-thiadiazolo [4,5-a] benzimidazole in 10 ml of methanol was added 250 µl of methanol. cl phenethylmercaptan. Comparison with an authentic sample of 2-mercaptobenzimidazole obtained from Aldrich Chemical Co. the substrate was found to undergo complete conversion to 2-mercaptobenzimidazole.

Example 55

Reaction of 3 - [(4-methylphenyl) sulfonyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole with phenethylmercaptan

To a suspension of 31 mg of 3 - [(4-methylphenyl) sulfonyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole in 10 mL of methanol was added 313 µl of phenethyl mercaptan. Comparison with an authentic sample of 2-mercaptobenzimidazole obtained from Aldrich Chemical Co. the substrate was found to undergo complete conversion to 2-mercaptobenzimidazole.

Example 56

Reaction of 5-amino-3-methoxy-1,2,4-thiadiazole with phenethyl mercaptan

To a solution of 250 mg of 5-amino-3-methoxy-1,2,4-thiadiazole in 10 ml of methanol was added 1.3 ml of phenethyl mercaptan. After completion of the reaction, the solvent was evaporated. The crude material is purified by chromatography. 236 mg of 3-carbamoylisourea are obtained. The structure of this compound was confirmed by X-ray analysis. ^X H-NMR (CDC1 _3, CT): 10 (br s, 1, NH), 6.55 (br d, 2H, NH?), 5.55 (br s, 1H, NH), 3.75 ( s, 3H, OCH ₃ ) ppm (in solution, this compound may exist in the tautomeric form of 1-thiocarbamoyl isourea, thus giving 1 NH ₂ and 2 NH in the NMR spectrum). IR (KBr): 3240, 3282, 3266, 3169, 1626, 1601, 1519, 1465, 1411, 1380, and 1098 cm @ ^-1 . MS (m / z): 133 (M +), 117 (M + - _NH2).

100 (M @ + - SH).

Example 57

Reaction of 3 - [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl)] - 1,2,485

-thiadiazolo [4,5-a] benzimidazole with phenethylmercaptan

Phenethylmercaptan (120 / <0.90 mmol) is added to a suspension of 3 - [(4-4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl]] - 1,2,4-thiadiazolo [4, 5-a] benzimidazole (300 mg, 0.887 mmol) in methanol (150 mL) and 0.1 M hydrochloric acid (38 mL). After stirring the mixture for 51 hours at room temperature, the mixture was neutralized with aqueous sodium bicarbonate to pH 6 and extracted with ethyl ether. The ether layer was dried over sodium sulfate and evaporated. The crude material was purified by chromatography (gradient elution: 10% ethyl acetate with hexane to 30% ethyl acetate with hexane). 110 mg of diphenethyldisulphide (92% yield from phenethylmercaptan), 63 mg of 2-oxo-2- (4-methoxy-3,5-dimethyl-2-pyridyl) acetic acid methyl ester (yield 37.6% of the title product) are obtained. of said 1,2,4-thiadiazolo [4,5-a] benzimidazole), 44 mg of 3 - [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl)] - 1,2,4-thiadiazolo [ 4,5-a] benzimidazole (14.6% recovered starting material) and 2-mercaptobenzimidazole (46 mg, 40% yield in the title 1,2,4-thiadiazole [4,5-a] benzimidazole).

Methyl 2-oxo-2- (4-methoxy-3,5-dimethyl-2-pyridyl) acetate: ^X H NMR _(CDCl3, C): 8.45 (s, 1 H, Ar H), 4.1 (s, 3H, _OCH3), 3.85 (s, 3H, OCH, 2.65 (s, 3 H, ArCHj, 2.4 (s, 3H, Ar ₃₎ ppm. IR (KBr): 1747, 1703, 1468, 1394, 1310, 1242, 1206, 1120, 1004, 740 cm ^*. MS (m / z): 224 (m + + HO), 164 (m - COOMe), 136 (m - COOMe - WHAT) .

2-Mercaptobenzimidazole: this material was found to be identical to an authentic sample obtained from Aldrich Chemical Co. ^(X of NMR, IR and TLC).

Difenetyldisulfid: ^X H NMR (CDC1 _3, d): 3.03 (m, 8H,

2CH ₂ CH ₂ ), 7.27 (m, 6H, ArH), 7.30 (m, 4H, ArH) ppm. ^{X 3} C NMR spectrum (CDC1 _3, d): 35.79, 40.27, 126.46, 128.57 128.67 and 140.08.

Example 58

Reaction of 3- (4-methyl-piperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole with thiophenol

A solution of 3- (4-methylpiperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole dihydrochloride (1.444 g, 4.31 mmol) and thiophenol (1.43 mL, 12.94 mmol) in methanol ( 400 mL) and 1N HCl (120 mL) were stirred at room temperature for 3.5 days. The material was evaporated. A solid residue was obtained which was partitioned between ether (3 x 100 mL) and water (20 mL). The ether layer was dried over sodium sulfate and the solvent was evaporated. 753 mg of diphenylsulfide are obtained (yield 53.3%). The aqueous layer was neutralized by dropwise addition of 2N NaOH at 0 ° C and then extracted with dichloromethane (3 x 100 mL). The dichloromethane layer was dried over sodium sulfate and evaporated. There was thus obtained 1- [1-imino- (5-methyl-piperazin-1-yl) -methyl-1H-benzimidazole-2-thiol as a solid (1.13 g, yield 95.1%). ^X H-NMR (DMSO-d _e, d): 2.19 (s, 3H, N-Me), 2.33 (br s, 4H, CH ₂ CH ₂ CH ₂ -), 3.24 (br s, 4 H , 2 CH ₂ CH ₂ -), 7.14 to 7.23 (m, 4H, Ar H. ^{X 3} C NMR spectrum (DMSO-d _p, d)): 44.81, 45.11, 53.59, 109, 52, 110.42, 123.09,

123.89, 131.47, 131.57, 149.34 (C = NH), 166.89 (CSH).

Example 59

Reaction of 3-benzoyl-1,2,4-thiadiazolo [4,5-a] benzimidazole with thiophenol

A solution of thiophenol (1.08 mL, 10.47 mmol), 3-benzoyl-1,2,4-thiadiazolo [4,5-a] benzimidazole (975 mg, 3.49 mmol) in methanol (400 mL) and 1N HCl solution (120 mL) was stirred at room temperature for 16 h. The solution was evaporated under reduced pressure to remove methanol. The aqueous mixture was neutralized to pH 7.0 with solid sodium bicarbonate and extracted with dichloromethane. The organic layer was dried over sodium sulfate. Evaporation gave a solid. This material was purified by column chromatography. The following compounds are thus obtained:

Diphenyldisulfide: (700 mg solid, = 0.69, 10% ethyl acetate with hexane), which by NMR was identical to diphenylsulfide from Aldrich Chemical. ^X H-NMR (CDCl ^ CT): 7.3 to 7.35 (m, 2H, Ar H), 7.35 7.45 (m, 4H, Ar H), 7.63 7.68 (m, 4H, ArH) ppm. ¹³ C NMR (CDCl ₃ , cf): 127.326, 127.703, 129.241 and 137.219.

2-Mercaptobenzimidazole (180 mg, 34.3% yield, R _x = 0.46, 20% ethyl acetate with hexane) which was identical (according to NMR spectrum) to 2-mercaptobenzimidazole from Aldrich Chemical.

Benzoyl formate methyl ester (120 mg, 21% yield, R _x = 0.57, 20% ethyl acetate with hexane), which was identical to Aldrich Chemical's methyl benzoyl formate by NMR spectrum. ³ C NMR spectrum (CDCl ₃ , cf): 52.67, 128.86, 130.03, 132.44, 134.89, 164.01 (C = O), 185.98 (C = O). IR: 1740 with 1687 cm @ ^-1 .

Example 60

Reaction of the 1,2,4-thiadiazolo [4,5-a] benzimidazole derivative with 2-mercaptoethanol. Determination of t ₂ values

The calculated amount of 1,2,4-thiadiazolo [4,5-a] benzimidazole derivative (final solution concentration 5.10 ^-3 M) and phenol (118 mg, final solution concentration 5.10 ^{-3 and} M) are dissolved in methanol (250 ml) in volumetric bank. Transfer 100 ml of this solution to a clean graduated flask and stir the resulting solution at room temperature. 100 µl of 2-mercaptoethanol was added over 60 seconds with the syringe tip inserted into the solution (final solution concentration 1, 15 ^{x 10 2} M). The progress of the reaction was monitored by HPLC (Hewlett Packard Model 1100) with a PE express 3.3 cm C18 column and a UV detector set at 254 nm. The column is eluted with 70% 50 mM ammonium acetate and 30% acetonitrile mobile phase.

The percent completion of the reaction was calculated as follows:

At time 0, 100% of the starting material remained unreacted.

At time t the percentage of unreacted starting material = [h / h at time t] / [h / h at time 0].

vzor.y vnic. 'samples ott CFL

100%. The percentage of unreacted starting material was plotted against the time scale. The value of t _{x Z 2} is the time point corresponding to 50% of the unreacted starting material.

Reaction of tricyclic 1,2,4-thiadiazoles with mercaptoethanol at pH 7.0

Y

group Y ^Tx _{/ 2} at pH = 7.0 MeO 0.31 h Me N 2 1.5 h morpholino 2.4 h 4-methylpiperazinyl 6,7 h phenyl 45 h methyl 59 h 2-pyridyl 134 h acetyl 110 h morpholinomethyl 98 h dimethylaminoethyl 64 h

Example 61

Effect of compounds of formula I on gastric acid secretion in rats

Fixed, adult (140-240 g) male Sprague-Dawley rats were kept 24 hours without food but with water. Thereafter, a total volume of 1-1.5 ml of a compound of formula I (300 mol / kg) was administered orally with sodium gastric sodium on various days. After two hours, the rats were anesthetized with a combination of pentobarbital and thiopental, the abdomen was opened, the pylorus was ligated, and tracheal, gastric and peripheral venous cannulas were inserted. The stomachs were washed with 10 ml of 0.9% sodium chloride solution every 10 minutes for 30 minutes. Liquids washed out of the stomach were collected in reservoirs to determine basic acid secretion. The acid content was determined for each gastric eluted sample by back titration with 0.02 M NaOH to pH 7.0. Then, 5 ml of 8% peptone meal (pH 5.5) was mixed into the stomach, mixed and harvested after 10 minutes for 2 hours. For each gastric washed sample containing the peptone meal, the acid content was determined by back titration with 0.02 M NaOH to pH 5.5.

For the control diluent (n = 6), the acid content stimulated with 8% peptone was recorded as 160 mmol / 30 minutes after 1 hour, whereas in rats dosed with 7-methoxy-3 - [(4-methoxy-3, 5-dimethyl-2-pyridyl) oxomethyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole, an acid level of 20 (mmol) was observed for 30 minutes after 1 hour. 7-Methoxy-3 - [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl)] - 1,2,4-thiadiazolo [4,5-a] benzimidazole proved significant (p <0.05) inhibition of food-stimulated acid secretion at 300 mole / kg.

Example 62

Effect of compounds of formula I on gastric acid secretion in rats (dose-dependent studies)

Fixed, adult (140-240 g) male Sprague-Dawley rats were kept 24 hours without food but with water. They were then orally administered with sodium gastric sodium to a total volume of 1-1.5 ml of four different doses (0.3, 3, 30 and 300 µmoles / kg) of each compound on different days. After two hours, the rats were anesthetized with a combination of pentobarbital and thiopental, the abdomen was opened, the pylorus was ligated, and tracheal, gastric and peripheral venous cannulas were inserted. The stomachs were washed with 10 ml of 0.9% sodium chloride solution every 10 minutes for 30 minutes. Liquids washed out of the stomach were collected in reservoirs. The acid content was determined for each gastric eluted sample by back titration with 0.02 M NaOH to pH 7.0. Then 5 ml of 8% peptone meal (pH 5.5) was mixed into the stomach, mixed and withdrawn every 10 minutes for 2 hours. The acid content was determined for each gastric eluted sample containing the peptone meal by back titration with 0.02 M NaOH to pH 7.0. After measuring the basal acid content for at least 30 minutes, the acid content was measured over a two hour intravenous infusion of histamine (5 mg / kg).

Figure 3 shows the stomach acid content (mmol / min) after dilution and 4 drops of 7-methoxy-3 - [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl]] - 1,2,4 -thiadiazolo [4,5-a] benzimidazole (0.3, 3, 30 and 300 mmol / kg) in anesthetized rats.

7-Methoxy-3 - [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl)] - 1,2,4-thiadiazolo [4,5-a] benzimidazole in doses of 3, 30 and 300 µmoles / kg showed significant (p <0.05) inhibition of histamine-stimulated acid secretion.

Example 63

In vitro inhibition of gastric acid secretion by 3- (4-methyl-1-piperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole dihydrochloride

Acid secretion was measured indirectly by accumulation of weakly basic ^x4 C-aminopyrine in isolated gastric glands of mice. This test is performed in polypropylene Eppendorf tubes containing 0.5 ml of resuspended mouse glands. The tubes further contain test drug, acid secretagogues (e.g., histamine, dibutyryl-cyclic AMP (cAMP), carbachol) and ¹⁴ C-aminopyrine. The tubes were incubated for 60 minutes at 37 ^° C and rotated continuously. The reaction was stopped by centrifuging the gland suspension for 5 minutes at 1500 x g. The supernatant was pipetted off. A pellet containing intact stomach glands remained. Wash the pellet vigorously overnight in 1 ml

Protosole (Amersham). After acid neutralization by addition of scintillation fluid, the radioactivity is counted by a beta counter.

pellet directly corresponds

Every test point

Amount of radioactivity Amount of acid that was performed three times.

acetic acid (Beckman) captured in was secreted.

In each experiment, an energetically independent consumption was evaluated

0.1 mM dinitrophenol and basal acid secretion in the absence of acid secretion stimulating agent. These values were then subtracted from the corresponding results to calculate basal (basal) acid secretion or acid secretion stimulated by acid secretagogues.

Mouse glands correspond to a variety of conventional secretagogues and post-receptor mediators, but not gastrin. Maximum stimulation of acid secretion is achieved with 1 mM cAMP, 0.1 mM histamine, 0.1 mM IBMX, 10 µM carbachol, 10 µM forskolin, 10 µM calcium ionophore A23187, and 1 µM tapsigarin. Each experiment was repeated several times and all results are expressed as% of maximum stimulation. For the purpose of comparing the relative activity of the compounds, each experiment contains positive controls using omeprazole for post-receptor / cAMP mediated responses and ranitidine, which inhibits histamine-induced acid secretion.

3- (4-Methyl-1-piperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole dihydrochloride completely inhibits cAMP and histamine-stimulated acid secretion at 100 µM. Using the above method, the ED value _of this compound was found to be 50 ^ 4 M.

Example 64

Inhibition of cathepsin B, cathepsin L and papain by 1,2,4-thiadiazoles and 1,2,4-thiadiazolo [4,5-a] benzimidazole derivatives; enzyme analyzes and kinetic measurements

The conditions for the above experiments can be found in the following references: Menard R. et al., Biochemistry 1990, 29, 6706-6713, Fox et al., Biochemistry 1992, 31, 12571-12576, and Cannoa E. et al., Biochemistry. 1996, 35, 8149-8157. A typical experiment consisted of a selected inhibitor concentration such that maximal inhibition was achieved in less than two hours, complete curve fitting (ie fluorescence versus time) and data analysis. The analysis gave two parameters:% inhibition once the steady state was reached and a rate constant that represents the rate at which this steady state was reached. The enzyme activity typically decreases with time until the maximum level of inhibition (i.e., steady state) is reached, where the enzyme activity remains constant. Since significant activity values could still be detected in the stable state (i.e. inhibition is not complete), the data were adjusted according to equation (1), which is normally used for slow-binding reversible inhibitors:

(ν _χ - in _o ). [1 - e ^_R obst ^c ] [P] = in _o .t + ------------------------- ------ (1) k

θ% inhibition = (1 - ν _{± /} νθ) 100 (2)

In this reaction, [P] means the concentration of the product (obtained from the detected fluorescence), means the first-order rate constant to achieve a stable state, v _o means the initial rate that corresponds to the rate in the absence of inhibitor, and means the rate of inhibited white state. % inhibition was obtained where the rate measured in the absence as in. Example

Below:

j simple k

he

EI k

of f

For this mechanism, the value would correspond to k = k. [inh] + otos on enzyme in the equation (2), the inhibitor was used mechanism of this process is determined experimentally to

of e

The k value varies with the inhibitor concentration. The value of k at> s off is often much smaller than k ^ linh] if / _ofas [ _inh ] can be used as an approximate k _on . This procedure is used in this study. The results are shown below:

[4-methylpiperazinyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole: cathepsin L: 98% inhibition at 200 µM [inhibitor]; k _{ot> e} / [inh] =

M ^x s ^-1 , cathepsin B: 68% inhibition at 200 [inhibitor]; k / [inh] =

M ^-1 = ^-1 , papain: 99% inhibition at 200 µM [inhibitor]; to _obQ / [inh]

M '^'s' ¹ .

1,2,4-thiadiazolo [4,5-a] benzimidazol-3-yl-carboxylic acid sodium salt:

cathepsin L: 98% inhibition at 50 µM [inhibitor]; k _otos / [inh] =

184 M ^-1 s ^-1 , cathepsin B: 85% inhibition at 200 µM [inhibitor]; k ^^ / tinh] =

M p ^{-1 _1,} papain: 99.6% inhibition at 200 / t M [inhibitor]; to _turn / [inh] =

131 M ^-1 s ^-1 .

3- [2-pyridylcarbonyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole: cathepsin L: 99% inhibition at 200 µM [inhibitor]; [inh] =

^Mxx with ^x , cathepsin B: 58% inhibition at 200 µM [inhibitor]; k _{ofc> and} / [inh] =

M ^-x p ^"x, papain: 79% inhibition at 1 / .mu.M [inhibitor]; k _ojoa / [inh] =

2479 M ~ ^x s ^_x .

3- [N-morpholinomethyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole: cathepsin L: 80% inhibition at 200 / · [inhibitor]; k ^^ / [inh] =

M ~ p ^{x _x,} cathepsin B: 60% inhibition at 200 [inhibitor]; k / [inh] = f 0190

M ^-x p ^_x, papain: 92% inhibition at 200 / OM [inhibitor]; k ^^ / [inh] =

M ~ ^x with ^_x .

1,2,4-thiadiazolo [4,5-a] benzimidazol-3-yl-L-proline methyl ester: cathepsin L: 99% inhibition at 10 &lt; M [inhibitor]; k / [inh] = 1050 M ^-x s- ^x , cathepsin B: 88% inhibition at 10 µM [inhibitor]; k / [inh] =

626 ^_X F ~ S ^X, papain: 97% inhibition at 200 / t M [inhibitor]; to _Qtoe / [inh]

356 M ^_x s ^_x .

3- [2- (N-morpholino) ethoxy] -1,2,4-thiadiazolo [4,5-a] benzimidazole: cathepsin L: 99% inhibition at 25 µM [inhibitor]; _{? Qfa?} / [inh] = 356 M ^-X with ^-X , cathepsin B: 91% inhibition at SO 4 M [inhibitor]; k _{Qt> and} / [inh] =

107 M ^x s ^x , papain: 99.6% inhibition at 0.66 µM [inhibitor]; k _{rev> a} / [inh] = 5560 M ^_x s ^_x .

{1,2,4-thiadiazole [4,5-a] benzimidazole-3-yl} carbonyl-L-leucylizoamylamid:

cathepsin L: 93% inhibition at 5 µM [inhibitor]; k _otoa / [inh] =

307 M ' ^x s' ^x , papain: 95% inhibition at 5 µA [inhibitor]; k _otoa [inh]

500 M ^-X with ^-X .

- {3-Methoxy-1,2,4-thiadiazolyl} carbamoyl-isoleucyl-isoamylamide:

cathepsin L: 99% inhibition at 3482 M ^-x with ^_x , 5 / ~ M [Inhibitor]; k / [inh] ÖBB cathepsin B: 56% inhibition of 1062 M ^x s- ^x , at 5 [Inhibitor]; k / [inh] both papain: 97 % inhibition at 1 / cM [Inhibitor]; k / [inh] both

3896 M ' ^x s' ^x .

Example 65

Determination of crystal structure of 5- (3-methoxy-1,2,4-thiadiazolyl} carbamoyl-isoleucyl-isoamylamide (T11AA) enzyme inhibitor complex with papain and actinidine: TllAA / papain complex and TllAA / actinidine complex

Purified papain was obtained commercially. Purified actinidine was obtained by aqueous extraction of homogenized kiwi fruit followed by ammonium sulfate fractionation and DEAE ion exchange chromatography. The actinidine / THAA and papain / TIIAA reactions were carried out according to the same procedure. Mercaptoproteins were isolated by mercaptoethanol-activated mercury agarose affinity chromatography. Proteins were eluted as mercury-bound derivatives. Mercury bound proteins (at 0.1% (w / v)) were incubated with an eight-fold molar excess of T11AA and EDTA at pH 7.5. Papain / TIIAA was redissolved to a concentration of 2.5% (w / v) in 67% methanol: ethanol (2: 1), 76mM NaCl and 1mM A100-73.

The papain / TIIAA crystals were grown by gaseous diffusion between droplets (droplet on the support). A portion of papain / TIIAA was incubated over a container containing 67% (2: 1) methanol / ethanol and 0.1M ethanolamine buffer, pH 9.3, at 23 ° C. Large individual crystals grew within 4-6 weeks.

Actinidine / T11AA was again dissolved at 0.5% (w / v) concentration in 20 mM MES buffer, pH 6.0, and 0.5 mM T11AA. Actinidine / TIIAA crystals were grown by the gaseous diffusion method between droplets (hanging nucleation technique). Above the reservoir at 4 ° C, a mixture of (1: 1) actinidine / TIIAA and a reservoir solution containing 20 mM MES buffer, pH 6.0 and 1.4 M ammonium sulfate was incubated. Over 7 to 10 days, large individual crystals grew.

These crystals were wax-attached to glass capillaries containing mother liquor. Data was obtained from a Siemens Multi-wire Detector mounted on a Rigaku RU200 X-ray Generator. Three rows of data were obtained for one papain / THAA crystal and two rows of data were obtained for two actinidine / T11AA crystals. XDS was used to reduce data. The relevant data series were jointly plotted. Protein crystals had the following single cell dimensions:

For papain / THAA: a = 4.29 nm, b = 4.99 nm, c = 9.57 nm, λ = 90.

For actinidine / TIIAA: a = 0.39 nm, b = 7.79 nm, c = 8.14 nm, δ = 90.

Both crystals belonged to the spatial group Ρ2 _χ 2 _ι 2 _ι . The data obtained for papain / T11AA was complete to address 0.22 nm (60% completeness, for 0.2 nm) with a total Rsym = 8.8%. Actinidine data was complete to address 0.27 nm with a total Rsym = 10%. XPLOR was used for structural simplification. 65 water molecules were modeled into the papain / T11AA structure. For papain / T11AA R = 18.4% and R = 20.4%. For * cryst free actinidine / T11AA R = 20.5% and R = 24.4%.

The electronic density maps for the papain / TllAA and actinidine / TllAA complexes exhibited continuous electron density based on their respective catalytic cysteine groups (Cys25). This demonstrates that T11AA reacts covalently with papain and actinidine to form protein / inhibitor complexes. T11AA was fully modeled at the papain active site, while the partial model of T11AA was fully modeled at the papain active site, obtaining a partial model of T11AA at the actinidine active site.

Kinetic data showed complete inhibition of enzymatic activity in the actinidine / THAA formulation and re-dissolution of actinidine / THAA crystals.

Example 66

Gastric ATPase enzyme inhibition assay

The enzyme used was hog H * / K * ATPase (Sachs et al., J. Biol. Chem. 1976, 251, 7690-7698). The modified procedure described by Yoda A. and Hokin L. E., Biochem. Res. Commun. 1970, 800-884. Potassium-stimulated ATP hydrolysis using gastric bladder hog, a composition enriched in H * / K * ATPase, is measured.

The difference between the activity in the presence of Mg '' and the presence of Mg ** and K * was taken as the enzyme activity. Nigericin, the K * ionophore, is also present in the (+) K * incubation mixture to provide K * access to the internal bladders. Hydrolysis activity is measured by quantitative analysis of the phosphomolybdenum complex. This complex exhibits a maximum optical density at 320 nm. The optical density of many drugs used to inhibit H * / K * ATPase interferes with this wavelength. Thus, a modification of this assay was used in which the phosphomolybdenum complex was reduced by Fiske and Subbarow reducing agent (1-amino-2-naphthol-4-sulfonic acid plus sodium sulfite). This shifts the optical density from 3 to 20 nm for the oxidized phosphomolybdenum complex to 600 to 700 nm. This modification has the additional advantage of providing means for automatic testing when multiple samples are tested. In this modification, the optical density of the test mixtures was read at 700 nm.

Baseline Mg ** values are measured in 2 ml MgCl ₂ , 2 mM Na ₂ ATP and 40 mM Pipes-tris, pH 6-10. 20 mM KCl and 10 µg / ml nigericin are added to determine the extent of K * stimulation. Test compounds or diluent are then added. Enzyme (10 µl / ml) is then added to initiate the reaction. The final volume was 200 µl. A protocol of these tests is given below.

volume per well reagent® Mg * alone K * plus nigericin 100 mM Pipes-Tris, pH 6.1 80/11 80 / U1 20mM MgCl 2 20 / H 20 / <1 200mM KC1 (-) 20/1 nigericin (200 / l / ml) 10 / ul 10 μΐ water, diluent or solution 20 μ.1 (-) containing the test substance 20mM ATP ¹³ 20 yU.1 20 μΐ Enzyme ^c 20/41 20 μΐ

® To reduce the number of additions, salt and water solutions can be combined as a single add. A further reduction in the number of additions can be achieved by using an enzyme to which nigericin is added (final concentration after addition of the enzyme 10 µm / ml).

ATP must be prepared in ice-cold distilled water immediately after addition.

^c Enzyme must be melted and diluted in buffer immediately before addition.

Blank tests (water controls) and phosphate standards (200 µl) were used for the tests: 0.005, 0.01, 0.25,

0.050, 0.075, 0.1 ... 0.5 mM standards. The order of addition of the reagents is generally as described above. However, it may be advantageous to add either enzyme prior to ATP if it is important to allow time for preincubation with the test compounds. The addition times of the last reagent are determined to achieve a uniform assay time.

The reaction is allowed to proceed for 30 minutes to 1 hour. The reaction is stopped by adding 50 µl of a solution prepared by adding 4 volumes of 2.5 M sulfuric acid and one volume of 1.25% (w / v) Fiske and Subbarow reagents. The color is allowed to develop for 10 minutes at room temperature. The optical density at 700 nm is determined. If a white precipitate is formed, a clear supernatant (after mixing and settling) can be used to determine the enzyme activity.

- [4-methylpiperazinyl] -1,2,4-thiadiazolo [4,5-a] benzimidazole: EC = 2.10 ' ⁶ M.

S o

3- [piperazinyl] -1,2,4-thiadiazole [4,5- a] benzimidazole:

EC = 1.10 ~ ⁶ M.

S o

3- [N-morpholinomethyl] -1,2,4-thiadiazole [4,5- a] benzimidazole:

EC = 2.10 ~ ⁱⁿ M.

S o

3- [2- (N-morpholino) ethylamino] -1,2,4-thiadiazolo [4,5- a] benzimidazole:

EC = 2.10 - ⁷ M.

S o

100

W ’/ W

Claims (3)

PATENT CLAIMS 1/3 (XI) RSH + R-S-S-R Fig. 1 /> / / 77 / - Fig. 2 Thus, the heterocyclic ring is a substituent independently of the group, nitro, amino, the di-alkylamino substituted group of the 1-3 group, the amino dialkyl group, the lower aminoheterocyclic cyclic group, the amino amino group or the oxy- (lower alkylene) group. a heterocyclic group, the heterocyclic ring is attached to any heteroatom or atom to form a stable optionally substituted with selected from lower hydroxyl, alkoxy, halogen, alkylamino, and heterocyclic with optionally substituents independently selected from lower alkyl nitro, hydroxy, alkoxy, group, atom halogen, alkylamino, amino, lower alkyl substituted with 1 to 3 substituents independently selected from hydroxyl, lower alkylcarbamoyl, cycloalkyl, phenyl, halophenyl a heterocyclic group, a heterocyclic group, a carboxy group and a lower alkoxycarbonyl lower acyl group, a lower alkoxycarbonyl lower alkylsulfonyl group, an amide group, a benzyl group, a phenyl group substituted by an amino group, a halogen atom, a hydroxyl group, a lower alkyl group, a lower alkyl group, or a di (lower alkyl) amino group, a group, an allyl group optionally (3) NR'R ' ¹ , wherein R' and R '' are as defined above, (4) ANR'R '' and AOR 'groups, wherein A is an amino acid group or a peptide of 2 to 3 amino acid groups, and R 'and R''are as defined above, (5) a lower 2- (alkoxycarbonyl) alkyl group, (6) a halogen atom, (7) groups of the general formula R ^and -CHOH-, in which R® is hydrogen, lower alkyl, aryl, lower arylalkyl, lower cycloalkyl, lower alkenyl, lower alkynyl or heterocyclic, the heterocyclic ring is attached at any heteroatom or carbon atom to form a stable structure, (8) groups of general R® of formula -C (= NOR ^{* o)} -, wherein R ¹⁰ is H, lower alkyl or lower arylalkyl, and ^R9 is lower alkyl, aryl, lower arylalkyl, lower even with a cycloalkyl group, a lower alkenyl group, a lower alkynyl group or a heterocyclic group, the heterocyclic ring is attached at any carbon atom to form a stable structure, (9) a lower alkoxy group optionally substituted by a di (lower alkyl) amino group, a morpholine group or 4-alkylpiperazinyl, aryloxy, lower arylalkoxy, lower cycloalkoxy, lower heterocycloalkoxy or heterocycloxy, (10) lower alkylsulfonyl, lower alkylsulfinyl, arylsulfonyl, arylsulfonyl, arylsulfonyl, arylsulfonyl, arylsulfonyl, 103 lower arylalkylsulfinyl, heterocyclo-sulfonyl, heterocyclo-sulfinyl, heterocyclotio, lower alkylthio, arylthio, lower arylalkylthio, optionally substituted with 1 to 2 substituents selected from lower alkyl, hydroxy, halogen, nitro, nitro, nitro, nitro, nitro, nitro, nitro, of formula NR'R '', OC (O) R ', OC (O) OR', OC (O) NR'R '', NR '(COR'), NHC (0) NR'R '', NHC ( O) R ', where R' and R '' are as defined above, (11) groups of the formula -C (= NOH) COOR ¹¹ , wherein R ¹¹ is lower alkyl, and (12) hydrogen, lower alkyl aryl, lower arylalkyl, lower cycloalkyl, each optionally substituted with 1 to 2 substituents selected from halogen, nitro, amino, hydroxyl, lower alkoxy, lower alkylamino, lower dialkylamines a lower alkylcarbamoyl group, NR'R '', OC (O) R ', OC (O) OR', OC (O) NR'R · ', NR' (COR '), NHC (O) NR 'R'', NHC (O) OR', in which R 'and R''are as defined above. (1) groups of the general formula - C = o IR ⁷ in which R ⁷ represents a hydrogen atom, a hydroxyl group, a lower alkyl group, a lower cycloalkyl group, a lower alkoxy group, a lower alkenyl group, a lower alkynyl group, an aryl group, a lower arylalkyl group, a heterocyclic group, a heterocyclooxy group, a heterocyclo- ) -alkylene, NR'R '', where R 'and R'' 101 are as defined above, and the group ANR'R '', AOR 'wherein A is an amino acid group or a peptide of 2 to 3 amino acid groups, and R 'and R' 'are as defined above, wherein the heterocyclic group is optionally substituted with a lower alkoxy group, a lower alkyl group, an amino group, a di (lower alkyl) amino group or mono (lower) (2) a heterocyclic group, a lower alkylene-heterocyclicalkylene-amino-heterocyclic group, an amino- (lower alkylene) -hetero (lower alkyl) - (lower alkylene) heterocyclyl group, in the structure, A process for reacting a compound containing a thiol group, characterized in that its thiol group is converted to a disulfide group by reacting a compound containing a thiol group with a 1,2,4-thiadiazole compound containing a structural moiety. or a pharmaceutically acceptable salt thereof, wherein R ¹ , R ² , R ³ and R ^{1 are} independently hydrogen, lower alkyl, halogen, nitro, hydroxyl, lower alkoxy or NR'R ¹ ' , OC (O) R ', OC (O) OR', OC (O) NR 'R'',NR' (COR '), NHC (O) NR' R '', NH (CO) OR ', where R 'and R''are independently selected from hydrogen, lower alkyl, aryl or arylalkyl, or NR'R''is a 5- or 6-membered ring containing a (CH ₂ ) _n group wherein n is 4 or 5, and Y is selected from: - (2-hydroxyethyl) -1-piperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 36. The method of claim 29, wherein the thiadiazole compound is a compound wherein G is an optionally substituted phenyl group. 37. The process of claim 36 wherein the thiadiazole compound is 3- (4-phenylpiperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 38. The process of claim 36 wherein the thiadiazole compound is 3- (4- (4-methoxyphenyl) piperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 39. The process of claim 36 wherein the thiadiazole compound is 3- (4- (3-chlorophenyl) piperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 40. process according to claim 29 c i sa t ý m that sa v like him thiadiazole compound uses compound, v which G stands for benzyl group. 41st process according to claim 40, s n a č u j ú c i sa t ý m that sa v like him thiadiazole compound uses 3- (4-Benzylpiperazinyl) -1,2,4-thiadiazolo [4,5- a] benzimidazole. 42. The method of claim 29, wherein the thiadiazole compound is a compound wherein G is cinamyl. 43. The method of claim 42, wherein the thiadiazole compound is 3- (4-cinamylpiperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 110 44. The process of claim 29 wherein the thiadiazole compound is a compound wherein G is a 2-pyridyl group. 45. The process of claim 44, wherein the thiadiazole compound is 3- (4- (2-pyridyl) piperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 46. The method of claim 29, wherein the thiadiazole compound is a compound wherein G is a 3-amino-2-pyridyl group. 47. The method of claim 46, wherein the thiadiazole compound is 3- (4- (3-amino-2-pyridyl) piperazinyl) -1,2,4-thiadiazolo [4,5- a] benzimidazole. 48. Method by claim 29, p c i sa because of sa v like him thiadiazole compound uses compound, v which G stands for A 2-pyrimidyl group. 49. Method by claim 48, p c i sa by using 3- (4- (2-pyrimidyl) piperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole as the thiadiazole compound. 50. The method of claim 29, wherein the thiadiazole compound is a compound wherein G is 1- (4-chlorophenyl) -1-phenylmethyl. 51. The method of claim 50, wherein the thiadiazole compound is 3- (4- (1- (4-chlorophenyl) -1-methylphenyl) piperazinyl) -1,2,4-thiadiazolo [4, 5-a] benzimidazole. 52. The method according to claim 29, wherein: The method of claim 1, wherein 3- (4-acetyl-1-piperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole is used as the thiadiazole compound. 53. The method of claim 1, wherein the thiadiazole compound used of the formula wherein R ^1, R ^2, R ³ and R ⁴ are independently lower alkyl, hydrogen, amino, lower alkylamino, di (lower alkyl) amine, hydroxyl, lower alkoxy, halogen or piperazinyl and G represents an alkyl group (having 1 to 6 carbon atoms) optionally substituted with up to three substituents selected from hydroxyl, lower alkylcarbamoyl, phenyl, halogenphenyl, heterocyclic carboxy, lower alkoxycarbonyl, allyl, benzyl, phenyl optionally substituted with amino, halogen, hydroxyl, lower alkoxy, lower alkyl, lower alkylamino or di (lower alkyl) amino and heterocyclic groups nu 3 substituents selected from the group consisting of lower alkoxy, amino, halogen, optionally substituted 1 to nitro, hydroxyl lower alkyl, lower alkylamino and di (lower alkyl) amino. 54. The process of claim 53 wherein the thiadiazole compound is a compound wherein G is an optionally substituted lower alkyl group. 112 55. The process of claim 54 wherein the thiadiazole compound is 3 - ((4-ethylpiperazinyl) methyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 56. The process of claim 54, wherein 3 - ((4-propyl-1-piperazinyl) methyl) -1,2,4-thiadiazolo [4,5-a] is used as the thiadiazole compound. benzimidazole. 57. The process of claim 54 wherein the thiadiazole compound is 3 - ((4-butylpiperazinyl) methyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 58. The process of claim 54 wherein the thiadiazole compound is 3 - ((4- (2-hydroxyethyl) piperazinyl) methyl) -1,2,4-thiadiazolo [4,5-a] ] benzimidazole. 59. The method of claim 53, wherein the thiadiazole compound is a compound wherein G is an optionally substituted phenyl group. 60. The method of claim 59, wherein 3 - ((4-phenylpiperazinyl) methyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole is used as the thiadiazole compound. 61. The method of claim 59, wherein the thiadiazole compound is 3 - ((4- (4-methoxyphenyl) piperazinyl) methyl) -1,2,4-thiadiazolo [4,5-a]. ] benzimidazole. 62. The process of claim 59, wherein the thiadiazole compound is 3 - ((4- (4-amino) -phenylpiperazinyl) methyl) -1,2,4-thiadiazolo [4,5-a]. benzimidazole. 113 63. The method of claim 53, wherein the thiadiazole compound is a compound wherein G is benzyl. 64. The process of claim 63 wherein the thiadiazole compound is 3 - ((4-benzylpiperazinyl) methyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 65. The method of claim 53 wherein the thiadiazole compound is a compound wherein G is cinamyl. 66. The process of claim 65 wherein the thiadiazole compound is 3 - ((4-cinamylpiperazinyl) methyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 67. The process of claim 53 wherein the thiadiazole compound is a compound wherein G is a 2-pyridyl group. 68. The process of claim 67, wherein the thiadiazole compound is 3 - ((4- (2-pyridyl) piperazinyl) methyl) -1,2,4-thiadiazolo [4,5-a]. ] benzimidazole. 69. The method of claim 53 wherein the thiadiazole compound is a compound wherein G is a 3-amino-2-pyridyl group. 70. The method of claim 69, wherein the thiadiazole compound is 3 - ((4- (3-amino-2-pyridyl) piperazinyl) methyl) -1,2,4-thiadiazolo [4, 5-a] benzimidazole. 71. The method of claim 53, wherein the thiadiazole compound is used 114 is a compound wherein G is 2-pyrimidyl. 72. The process of claim 71 wherein the thiadiazole compound is 3 - ((4- (2-pyrimidyl) piperazinyl) methyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. . 73. The method of claim 53 wherein the thiadiazole compound is a compound wherein G is (1- (4-chlorophenyl) -1-phenylmethyl). 74. The process of claim 73 wherein the thiadiazole compound is 3 - ((4- (1- (4-chlorophenyl) -1-phenylmethyl) piperazinyl) methyl) -1,2,4. -thiadiazolo [4,5-a] benzimidazole. 75. The process of claim 3 wherein the thiadiazole compounds are those wherein Y is a halogen atom. 76. The process of claim 75 wherein the thiadiazole compounds are those wherein Y is bromo. 77. The process of claim 76 wherein 3-bromo-1,2,4-thiadiazolo [4,5-a] benzimidazole is used as the thiadiazole compound. 78. The process of claim 3 wherein the thiadiazole compound is a compound wherein Y is a halomethyl group. 79. The method of claim 78 wherein the thiadiazole compound is 3-bromomethyl-1,2,4-thiadiazolo [4,5-a] benzimidazole. 115 80. The process of claim 3 wherein the thiadiazole compound is 3- (4-methylphenylsulfonyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 81. The method of claim 1, wherein the thiadiazole compound used of the formula wherein R ^x, R ^2, R ³ and R ⁴ are independently lower alkyl, hydrogen, amino, lower alkylamino, di (lower alkyl) amino, hydroxyl, lower alkoxy, R and R groups, the alkyl amino group R 'and R''optionally selected and prole selected from the group, phenyl, and di (lower alkyl) amino. the atom is independently selected from lower, phenyl substituted by hydroxyl lower alkylamino, carboxy lower halogen or piperazinyl alkyl and lower, 'and R' 'benzyl, or lower alkoxycarbonyl or together with the N-group to which they are attached form substituted, saturated heterocyclic group of morpholinyl, piperidinyl, pyrrolidinyl and the optional substituents therein are lower alkyl, carboxy, amine lower alkoxycarbonyl 82. The process of claim 1, wherein the compound is as a compound in which as the R ' group. 81 wherein the thiadiazole compound used as R ¹ is a lower alkyl 83. The method of claim 82, wherein 116 by using it as a thiadiazole compound 3-dimethylaminomethyl-l, 2,4-thiadiazole [4,5- a] benzimidazole. 84. The process of claim 82 wherein the thiadiazole compound is 3-diethylaminomethyl-1,2,4-thiadiazolo [4,5-a] benzimidazole. 85. The process of claim 82 wherein the thiadiazole compound is 3-dipropylaminomethyl-1,2,4-thiadiazolo [4,5-a] benzimidazole. 86. The process of claim 82 wherein the thiadiazole compound is 3-dibutylaminomethyl-1,2,4-thiadiazolo [4,5-a] benzimidazole. 87. The method of claim 81, wherein the thiadiazole compound is a compound wherein R ' and R ' with the nitrogen atom to which they are attached form a morpholine ring structure. 88. The process of claim 87 wherein the thiadiazole compound is 3-morpholinomethyl-1,2,4-thiadiazolo [4,5-a] benzimidazole. 89. The method of claim 1, wherein the thiadiazole compound is a compound wherein Y is a phenyl group optionally substituted with 1 to 3 substituents selected from lower alkyl, hydroxyl, nitro, amino, lower alkylamino. , di (lower alkyl) amino and lower alkoxy. 90. The method of claim 89, wherein the thiadiazole compound is 3-phenyl-1,2,4-thiadiazolo [4,5-a] benzimidazole. The method of claim 89, characterized by 117 by using it as a thiadiazole compound 3- (2-nitrophenyl) -1,2,4-thiadiazole [4,5- a] benzimidazole. 92. The method of claim 89, wherein the thiadiazole compound is used 6-amino-3-phenyl-1,2,4-thiadiazolo [4,5-a] benzimidazole. 93. The method of claim 89, wherein the thiadiazole compound is used therein 7-amino-3-phenyl-1,2,4-thiadiazolo [4,5-a] benzimidazole. 94. The process of claim 1, wherein the thiadiazole compound is a compound wherein Y is a 2-pyridyl group optionally substituted with 1 to 3 substituents selected from lower alkyl, hydroxyl, nitro, amino, lower. alkylamino, di (lower alkyl) amino and lower alkoxy. 95. The process of claim 94 wherein the thiadiazole compound is 3- (2-pyridyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 96. The method of claim 1, wherein the thiadiazole compound is a compound wherein Y is a 2-pyrazinyl group optionally substituted with 1 to 3 substituents selected from lower alkyl, hydroxyl, nitro, amino, lower. alkylamino, di (lower alkyl) amino and lower alkoxy. 97. The process of claim 96 wherein the thiadiazole compound is 3- (2-pyrazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 98. The process of claim 1 wherein the thiadiazole compound is a compound wherein: 118 Y represents an optionally substituted aminopyridyl group. 99. The process of claim 98, wherein the thiadiazole compound is 3- [2-pyridylamino] -1,2,4-thiadiazolo [4,5-a] benzimidazole. 100. The process of claim 98 wherein the thiadiazole compound is 3- [3-pyridylamino] -1,2,4-thiadiazolo [4,5-a] benzimidazole. 101. The process of claim 1 wherein the thiadiazole compound is a compound wherein Y is an optionally substituted lower alkyleneaminopyridyl group. 102. The process of claim 101 wherein the thiadiazole compound is 3- [2-pyridylmethylamino] -1,2,4-thiadiazolo [4,5-a] benzimidazole. 103. The process of claim 101, wherein 3- [N-methyl- (2-pyridylethyl) amino] -1,2,4-thiadiazolo [4,5-a] is used as the thiadiazole compound. benzimidazole. 104. The method of claim 1 wherein the thiadiazole compound is a compound wherein Y is imidazolylmethyl. 105. The process of claim 104 wherein the thiadiazole compound is 3- (imidazolylmethyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 106. The process of claim 1 wherein the thiadiazole compound is a compound wherein Y is 1,2,4-triazolylmethyl. 107. The method of claim 106, wherein 119 by using it as a thiadiazole compound 3- (1,2,4-triazolylmethyl) -1,2,4-thiadiazole [4,5- a] benzimidazole. 108. The process of claim 3 wherein the thiadiazole compound is 3- (4-methylphenylsulfonyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 109. The process of claim 1 wherein the thiadiazole compound is a compound wherein Y is a group of the formula - C = o I R ⁷ wherein R ⁷ is -ANR'R '·, wherein A is an amino acid group. 110. The process of claim 109 wherein A in the compound used is a leucine group. 111. The process of claim 110 wherein R ' in the compound used is lower alkyl and R ' is hydrogen. 112. The method of claim 111, wherein a compound of formula (I) is used 113. A process for reacting a compound containing a thiol group, wherein the thiol group is converted to a disulfide group by reacting the compound containing a thiol group with a thiadiazole. 120 of formula III (III), and pharmaceutically acceptable salts thereof, wherein R ⁵ and R ^e are independently selected from lower alkyl, halogen, hydroxyl, lower alkoxy NR'R '*, OC (O) R ' NR '(COR'), NHC (O) NR'R '', NH (O) OR ', wherein R' and the above meaning in claim 1 or NR'R '' five- or wherein n in claim 1 . hydrogen, nitro, or groups OC (O) OR ', OC (O) NR'R'',R''have is from the group N (CH ₂ ) _n , Y has a six membered ring consisting of the number 4 or 5, and the meaning given therein 114. A method in that the compounds in which claim 113, Black, Russian thiadiazole compound such as R ^a and R ⁶ represents C D UA using hydrogen. s and you 115. A method according to characterized in that it is the compound in which Claim 114, important as a thiadiazole compound Y is D uj are using the most, and R ⁷ represents an aryl or a lower group. A lower alkoxy group according to claim 114, wherein the thiadiazole 3-acetylimidazo [1,2-d] -1,2,4-thiadiazole is present. 116. The method wherein Compound (c) is used 117. The method of claim 114, wherein: 121 by treating it as the thiadiazole 3-benzoylimidazo [1,2-d] -1,2,4-thiadiazole. 118. 3,5-Disubstituted 1,2,4-thiadiazole of formula In ⁿ wherein Q is (a) a group -T [-AMA-] L, wherein the intervening group attached to and selected from the group of the compound of the compound uses a thiadiazole nucleus in general chemically means O II C L is a protecting group a peptide group on N-terminal or terminal wherein R ¹ and R ¹¹ are as defined below amino acid - [NH-CHA ¹ -CO], wherein A ^{x is} acidic or is n'-substituent and for the Y group peptide means any known n is an integer from a -AMA (b) or an amino group -NHPh or diphenylguanidine of the general formula I in which Ph represents a phenyl group optionally substituted 122 a hydroxyl group, a lower alkoxy group or an amino group, Y * represents lower alkyl, lower alkoxy, amino, carboxyl, lower alkoxycarbonyl or 1-piperazinyl optionally substituted at the 4-position with lower alkyl, lower alkyl substituted with 1 or 2 substituents selected from hydroxyl, lower alkylcarbamoyl, phenyl, halogenphenyl, heterocyclic, carboxy and lower alkoxycarbonyl, benzyl, phenyl optionally substituted by amino, halogen, hydroxyl, lower alkoxy, lower alkyl, lower alkylamino or di (lower alkyl) heterocyclic group optionally substituted with 1 to 3 substituents selected from nitro, amino, halogen, hydroxyl, lower alkoxy, lower alkyl, lower alkylamino or a di (lower alkyl) amino group, a 1,1-diphenylmethyl group in which both phenyl rings are optionally substituted with a halogen atom, an amino group, a hydroxyl group, or a lower alkoxy group, a 2-pyridyl group wherein the pyridyl ring is optionally substituted with 1 to 3 substituents selected from nitro, amino, halogen, hydroxyl, lower alkoxy, lower alkyl, lower alkylamino or * di (lower alkyl) amino, or -CH 2 -CO-NH- (lower) alkyl with the proviso that when Q is -NHPh then Y ^{1 is} not alkoxy, dialkylamino, hydroxyalkylamino and di (hydroxyalkyl) amino and if Y 'is piperazinyl substituted in the 4-position, then Q is not -T- [AMA ] -L. 119. The compound of claim 118 wherein Q is an amino acid group of formula 123 — NH - CO - NH - CH - CO - NH - B ₂ COOB ₂ 'Λ —CO — NH — CH — CO — NI or in which PG is an N-terminal protecting group selected from heterocyclocarbonyl, benzoyl, carbobenzyloxy and tert-butoxy, Α _χ is lower alkyl means a lower alkyl group optionally substituted by an amino group, a guanidine group or an N, N-di (lower alkyl) guanidine group and n is 1 or 2. 120. The compound of claim 119, wherein Y ' is selected from lower alkyl, lower alkoxy, amino, carboxyl, and lower alkoxycarbonyl. 121. Compounds according to claim 118 wherein Y is 1-piperazinyl optionally substituted in the 4-position by lower alkyl, lower alkyl substituted by 1 or 2 substituents selected from hydroxyl, lower alkylcarbamoyl, phenyl, halophenyl, heterocyclic , carboxy and lower alkoxycarbonyl, benzyl, phenyl optionally substituted with amino, halogen, hydroxyl, lower alkoxy, lower alkyl, lower alkylamino or di (lower alkyl) amino, 124 a heterocyclic group optionally substituted with 1 to 3 substituents selected from nitro, amino, halogen, hydroxyl, lower alkoxy, lower alkyl, lower alkylamino or di (lower alkyl) amino, 1,1-diphenylmethyl, wherein: both phenyl rings are optionally substituted with a halogen atom, an amino group, a hydroxyl group or a lower alkoxy group, a 2-pyridyl group wherein the pyridyl ring is optionally substituted with 1 to 3 substituents selected from nitro, amino, halogen, hydroxyl, lower alkoxy, lower alkyl, lower alkylamino or di (lower alkyl) amino, or -CH 2 -CO-NH- (lower) alkyl, and Q represents NHPh or diphenylguanidine of formula NH II - N - C - Ph II NH in which Ph represents a phenyl group optionally substituted by a hydroxyl group, a lower alkoxy group or an amino group. 122. The compound of claim 118 which is 123. The compound of claim 118 which is 125 124. The compound of claim 118 which is Process according to claim 1, characterized in that those thiadiazole compounds are used in which each of R ¹ , R ² , R ³ and R ⁴ is both a hydrogen atom or an alkoxy group. The process according to claim 2, characterized in that those thiadiazole compounds are used in which each of R ¹ , R ³ and R ⁴ represents a hydrogen atom and R ² represents either a hydrogen atom or a methoxy group. Process according to claim 3, characterized in that those thiadiazole compounds are used in which Y represents a group of the general formula 104 - C = Ο I R ⁷ as defined in claim 2, wherein R ⁷ is lower alkyl, lower arylalkyl, optionally substituted phenyl or naphthyl, optionally substituted heterocyclic, hydroxyl or lower alkoxy. A process according to claim 4, characterized in that a thiadiazole compound is used in which R ⁷ represents an optionally substituted heterocyclic group. The process according to claim 5, characterized in that those thiadiazole compounds are used in which R ⁷ represents a 2-pyridyl group either unsubstituted or substituted by 1 to 3 substituents selected from methyl and methoxy. The process according to claim 6, characterized in that those thiadiazole compounds are used in which R ⁷ represents a 3,5-dimethyl-4-methoxy-2-pyridyl group. The process according to claim 7, wherein the thiadiazole compound is 7-methoxy-3 - [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl] -1,2,4-thiadiazolo- [4,5-a] benzimidazole. The process according to claim 7, wherein the thiadiazole compound is 3 - [(4-methoxy-3,5-dimethyl-2-pyridyl) oxomethyl] -1,2,4-thiadiazolo [4,5- a] benzimidazole. Process according to claim 4, characterized in that those thiadiazole compounds are used in which R ⁷ is optionally substituted piperazine. 105 Process according to claim 1, characterized in that thiadiazole compounds of the general formula in which R ¹ , R ² , R ³ and R ^{4 are} independently lower alkyl, hydrogen, amino, lower alkylamino, di (lower) are used. alkyl) amine, hydroxyl, lower alkoxy or piperazinyl and G represents an alkyl group (having 1 to 6 carbon atoms) optionally substituted with up to three substituents selected from hydroxyl, lower alkylcarbamoyl, phenylhalophenyl, heterocyclic, carboxycarbonyl and lower alkoxy groups. The process according to claim 11, characterized in that a thiadiazole compound is used in which G represents a 4-methylpiperazinyl group. Process according to claim 11, characterized in that 3- (4-methylpiperazinylcarbonyl) -1,2,4-thiadiazolo (4,5-a) benzimidazole is used as the thiadiazole compound. Compounds according to claim 11, characterized in that a thiadiazole compound is used in which R 1 represents a group G which is a 4- (2-pyridyl) piperazinyl group. The process according to claim 14, characterized in that 3- (4- (2-pyridyl) piperazinylcarbonyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole is used as the thiadiazole compound. 106 Process according to claim 4, characterized in that those thiadiazole compounds are used in which R ^v represents an optionally substituted phenyl or naphthyl group. Process according to Claim 16, characterized in that thiadiazole compounds are used in which R ⁷ represents a phenyl group. Process according to claim 17, characterized in that 3- (oxophenylmethyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole is used as the thiadiazole compound. 19. The process of claim 11 wherein the thiadiazole compound is 3- (4- (benzyl) piperazinylcarbonyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. Process according to claim 4, characterized in that those thiadiazole compounds are used in which R ⁷ represents a hydroxyl group. 21. The process of claim 20 wherein the thiadiazole compound is 3-carboxy-1,2,4-thiadiazolo [4,5-a] benzimidazole. A process according to claim 3, characterized in that those thiadiazole compounds are used in which Y represents an optionally substituted heterocyclic group attached directly to the thiadiazole ring. A method according to claim 22, characterized in that those thiadiazole compounds are used in which the heterocyclic moiety of group Y is selected from pyridyl, piperazinyl, morpholinyl, pyrrolidinyl and pyrazinyl groups. 107 24. The process of claim 23 wherein the thiadiazole compound is 3- (2-pyridyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 25. The method of claim 23 wherein the thiadiazole compound is 3- (4-morpholinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 26. The method of claim 23 wherein the thiadiazole compound is 3- (1-pyrrolidinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 27. The method of claim 23 wherein the thiadiazole compound is 3- (2-pyrazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. The method of claim 2, wherein the compound containing the thiol group is an enzyme. The method of claim 1, wherein thiadiazole compounds of the formula wherein R ¹ , R ² , R ³ and R ^{4 are} independently lower alkyl, hydrogen, amino, lower alkylamino, di (lower) are used. alkyl) amino, hydroxyl, lower alkoxy, halogen or piperazinyl and G represents an alkyl group (1 to 6 carbon atoms) optionally substituted with up to three substituents selected 108 of a hydroxyl group, a lower alkylcarbamoyl group, a phenyl group, a halophenyl group, a heterocyclic group, a carboxy group and a lower alkoxycarbonyl group, an allyl group, an acetyl group, a benzyl group, a phenyl group optionally substituted with amino, halogen, lower alkoxy, alkyl, lower alkylamino or di (lower alkyl) amino, and heterocyclic optionally substituted with 1 to 3 substituents selected from nitro, hydroxyl, lower alkoxy, lower alkyl, amino, halogen, lower alkylamino, and di (lower) alkyl) amino group. 30. The process of claim 29 wherein the thiadiazole compound is a compound wherein G is an optionally substituted lower alkyl group. The process of claim 30, wherein the thiadiazole compound is 3- (4-methyl-1-piperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 32. The process of claim 30 wherein the thiadiazole compound is 3- (4-ethyl-1-piperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. The method of claim 30, wherein the thiadiazole compound is 3- (4-propyl-1-piperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 34. The process of claim 30 wherein the thiadiazole compound is 3- (4-butyl-1-piperazinyl) -1,2,4-thiadiazolo [4,5-a] benzimidazole. 35. The method of claim 29, wherein 3- (4109) is used as the thiadiazole compound. 3/3 · F, S basal histamine (5 mg / kg / h, i.v. amount of acid (mmol / 10 minutes) period of 10 minutes