PT99833A - A process for the preparation of anti-inflammatory compounds containing a substituted CHROMAN group - Google Patents

Description

Leukotriene D4 and C4 (LTD4 / LTC4) and leukotriene B4 (LTB4) are products of the metabolic pathway of arachidonic acid. LTD4 and LTC4 are associated with smooth muscle contraction and contracting guinea-pig ileum, human and guinea-pig bronchi and the human pulmonary artery and vein - LTB4 is associated with neutrophil stimulation and is characterized by chemotaxis, aggregation and degranulation. It is thought that LTB4 is an important mediator of inflammation. Elevated levels of LTB4 are detected in rheumatoid arthritis, gout, psoriasis, and inflammatory bowel disease. Thus LTB4 antagonists are useful in the therapy of such diseases.

Gastroenteroloav. 1985: 88-580-7 discusses the role played by arachidonic acid metabolites in inflammatory bowel disease.

British Medical Bulletin. (1983), vol. 39, No. 3, pp. 249-254, generally discusses the pharmacology and pathophysiology of leukotriene B4.

Biochemical and Biophysical Research Communications. Vol. 138, No. 2 (1986), pp. 540-546 discusses the pharmacology of an LTB4 specific antagonist having a structure different from that of the compounds of this invention.

The Journal of Medicinal Chemistry. 1977, Vol. 20. (3): discloses a compound similar to that of the comopostos of Formula I. The prior art generally describes the above compounds as LTD4 antagonists for use as anti-allergic compounds or as SRS-A antagonists, the substance - 4 - ϊ f

. Fig. and slowly reacts with anaphylaxis. In a marked contrast, compounds of Formula I are selective LTB2 antagonists useful in the treatment of inflammatory diseases.

U.S. Pat. 4,281,008, 3,822,148 and 4,006,245 generically present formulas which encompass compounds similar to those of Formula I but do not exemplify or otherwise permit the preparation and use of such compounds, nor does it indicate selective antagonistic activity against LTB4 of present invention. U.S. Patent No. 4,889,871 generically discloses formulas which encompass the compound 1 described in Scheme 1 referred to herein and which is used as an intermediate in the preparation of the compounds of this invention. The compounds are presented as useful anti-inflammatory agents.

Summary of the Invention

This invention encompasses compounds of the following formula and the stereoisomers and pharmaceutically acceptable salts thereof.

in which R represents lower alkyl of 1 to 6 carbon atoms, 3 lower alkenyl of 2 to 6 carbon atoms, or - (CH 2) n -; . wherein R represents cycloalkyl of 3 to 5 carbon atoms and e is 1, 2 or 3; 0

II is -CONH2 or -CNH2SO2 R2 wherein R2 is lower alkyl, phenyl, unsubstituted or substituted with lower alkyl; or twm *. ....

and n is an integer from 2 to 5;

These compounds are selective leukotriene antagonists (LTB2) with little or no leukotriene antagonism (LTD4) and are useful anti-inflammatory agents for the treatment of inflammatory bowel disease, rheumatoid arthritis, gout, asthma and psoriasis.

Detailed Description of the Invention

This invention encompasses the compounds of Formula I as previously described.

Preferred embodiments of the present invention are compounds of Formula Ia, and stereoisomers and pharmaceutically acceptable salts thereof,

wherein R 1 is propyl, 2-propenyl or cyclopropylmethyl, and R 1 is

It is implicit in this requirement that the tetrazole moiety consists of the tautomeric structures

There is)

(B) being used herein to represent the tetrazole compound.

Pharmaceutically acceptable salts such as ammonium, sodium, potassium, alkaline earth metal, tetraalkylammonium, etc. are encompassed by the invention. Scheme 1 shows a specific presentation of the method for preparing compounds of the invention. SCHEME 1

δ

ι i-9-

The present invention is further illustrated by the following examples which are not intended to be limiting.

Example 1

Referring to Scheme 1, 2.1 grams of compound 1 were dissolved in 50 ml of toluene and 15 ml of (COCl) 2 were added. The mixture was stirred at room temperature for 4 hours. The reaction was then quenched in vacuo to give a crude oil and 150 mL of CH 2 Cl 2 was added. The solution was then cooled to room temperature and NH 3 gas was bubbled through the solution for one hour. The reaction mixture was then poured into 150 ml of water, the layers were separated and the aqueous layer was extracted three times with CH 2 Cl 2. The mixture was then filtered and dried to give 1.45 grams of compound 2. 10

Example 2

CN

2 1.35 (2.79 mmol) grams of compound 2 were dissolved in 15 ml of CH 2 Cl 2 and 2.50 grams (9.77 mmol) of Burgess reagent 1 was added. The mixture was stirred at room temperature overnight and purified from the solvent to give 1.30 grams of compound 3.

Elements

Carbon

Hydrogen

Nitrogen

Calculated 72.23 7.58 3.01

Found: 72.23 7.62 3.03 1

Burgess, Reagent CH3C> 2CNS02NEt3 methyl (carboxysulfamoyl) triethylammonium hydroxide inner salt. J. Org. Chem. 38, 26 (1973)

958.2 mg of compound 2 and 203.4 mg of (CH3) 3 Si N3 were placed in the 40 ml reaction flask which was sealed and heated to 150 ° C overnight. Heating was maintained for an additional 44 hours over a total heating time of 64 hours. The reaction mixture was then passed through a silica column with a 5/95/1 mixture of CH3 OH / CH2 Cl2 / acetic acid. 100 mg of the product, compound 4, were obtained.

Elements

Carbon

Hydrogen

Nitrogen

Calculated 66.12 12.13 11.02

Found: 66.23 7.15 10.95 12

Example 4 Synthesis of Sulfonamides

A mixture of 2.9 g (6 mMol) of compound 1, 0.96 g of benzenesulfonamide, 0.96 g (7.8 mMol) of 4- (dimethylamino) pyridine, 1.08 g (6 mMol) of 1- [3- (dimethylamino) propyl] -3-ethylcarbodiimide hydrochloride, 5 g of 4A molecular sieves and 60 ml of dry dichloromethane was stirred at room temperature for 4 days. The reaction mixture was filtered and the filtrate was washed with 1 N HCl, water and brine. Evaporation of the dried solvent (Na2 SO4> 4) in vacuo provided crude product which was purified by silica gel chromatography (hexane / ethyl acetate / acetic acid, 65/34/1 as eluent) to provide 3.1 g of product .

Microanalysis: Theoretical C, 65.47, H, 6.62, N, 2.25 Found: C, 65.18; H, 6.67; N, 2.25;

Example 5 - ο; ι.

Ο Compound A (2.1 g) was dissolved in dry toluene and oxalyl chloride (1.2 equivalents) was added with stirring under argon. 1 drop of DMF was added and the reaction mixture was stirred at room temperature for 1 hour. The solvent was removed in vacuo and the residue was dissolved dry and ammonia gas was slowly bubbled through the solution over. . . 3 20 minutes. Water (100 cm @ 3) was added and the organic layer was separated, dried over magnesium sulfate and the volatiles were removed in vacuo. The resulting residue was purified by silica gel chromatography to provide compound (B) as a white solid (1.8 g).

Analysis: Calculated for C 28 H 35 N 5 • 6, 69.83, H, 7.32, N, 2.91 Found: C, 69.60. H, 7.23, N, 2.86 v '

Example 6 v '

The 3.0 g of compound B were dissolved in methylene chloride. 3-methylene (25 cm) containing Burgess reagent (4.0 g) and the mixture was stirred at room temperature overnight. At this point, the solvent was removed and the residue was purified by silica gel chromatography using ethyl acetate / hexane (2: 8) as the eluent. Compound (C) was isolated as a colorless oil (2.8 g).

Example 7 0

W

Compound (C) (2.8 g), sodium azide (1.2 g) and triethylamine chloride (1.2 g) were dissolved in 1-methyl-3-pyrrolidone (60 cm @ 3) and the solution was warmed at 150 ° C for 2 hours. The mixture was poured into 200 cm @ 3 of water, acidified.

with dilute HCl and then extracted with ethyl acetate. The organic layers were dried and evaporated in vacuo to provide a crude residue which was purified by chromatography on silica gel using ethyl acetate / hexane / acetic acid (50: 49: 1) as solvent. Compound (D) was obtained as a white solid (2.1 g).

I

Analysis for C28 H34 N4 O5 Calculated: C, 66.39; H, 6.76; N, 11.06 Found: C, 66.19; H, 6.87; N, 11.26. Example 8

Compound (E) (1.0 g) was converted to the amide compound (F) as shown in Example 5. 1.0 g of compound (F) was obtained by chromatography of the crude product on silica gel using ethyl acetate / hexane (3: 7) as eluent. 16%

Example 9

Compound F (1.0 g) was treated with Burgess reagent under conditions described in Example 6. The crude product thus obtained was purified on silica gel using hexane / ethyl acetate (2: 8) as the eluent. Compound G (870 mg) was isolated as a colorless oil.

Micro Analysis for C 29 H 35 N 5 O: Calculated: C, 72.93; H, 7.39; N, 2.93

Found: C, 72.45, H, 7.30, N 2.90

Example 10

Compound G (0.8 g) was converted to tetrazole H by treatment with sodium azide (330 mgs), 17-hydrochloride

triethylamine (0.3 g) in 1-methyl-2-pyrrolidone. (20 cm ) . The mixture was heated at 150 ° C for 2 hours and then partitioned between 2N HCl and ethyl acetate. The organic layer was removed, dried (MgSO4) and purified in vacuo to provide a crude oil. This material was purified by silica gel chromatography (ethyl acetate / hexane / acetic acid (50: 49: 1) as eluent) to afford 720 mg. of compound H.

Microanalysis for C 29 H 36 N 4 O 5 Calc'd: C, 66.90, H, 6.97 N, 10.76

Found: C, 66.54, H, 6.93, N, 10.88 The biological activity of the compounds of this invention was determined by the following test procedures.

Preparation of Human Neutrophils

Neutrophils were purified from venous blood from normal human donors using standardized

R dextran sedimentation, Ficoll x plate centrifugation > (Pharmacia) or sterile solution of Histopaque (Sigma) and hypotonic lysis of erythrocytes (Boyum, A., Isolation of Leukocytes from Human Blood: Further Observations, Scand J. Clin. 31, 1968). The purity of the isolated neutrophils was > 95%.

Neutrophil Deqranulation Assay Neutrophil degranulation was determined by measuring the release of myeloperoxidase activity to the medium of incubation. Neutrophils (3 x 10) in 1 ml of HBSS solution were preincubated with cytochalasin B (5 μg) at 37 ° C for 5 minutes, followed by preincubation with the test compounds for 7 days

minutes. Neutrophils were then incubated for 2 to 20 -8 minutes with LTB2 (5 x 10M) to induce degranulation. Following incubation, the samples were centrifuged and myelopexyxase was extracted from cell pellets by sonication in phosphate buffer containing 0.4% Triton X-100. Triton X-100 was also added to the floating elements to a concentration of 0.4%. The buoyant elements and the pill extracts were then assayed spectrophotometrically for myeloperoxidase activity by determining the rate of decomposition of Î ± -dianisidine as a hydrogen donor as described by Renlund, et al. (Renlund, D.G., MacFarlane, J.L., Christensen, R.D., Lynch, R.E., and Rothstein, G., A Ouantitative and Sensitive Method for Measurement of Methylsubsidase, Clinical Research 28: 75A, 1980). The activity of the myeloperoxidase released in the floating element was expressed as the percentage of the total average activity (most floating pill).

LTB Receptor Binding Assay.

Neutrophils (4-6X10) in 1 ml of Hank's balanced salt solution containing 10 mM HEPES buffer (HBSS), pH 7.4 and 30 μl of nordihydroguaiaretic acid were incubated with 0.6 × 10 3 Μ (H) LTB 4 in the presence or absence of test compounds. Incubation was performed at 0 ° C for 45 minutes and terminated by adding 5 ml of ice-cold HBSS followed by rapid filtration of the incubation mixture under vacuum through GF / C glass fiber filters. The filters were further washed with 10 ml of HBSS and the radioactivity was determined. Specific binding was defined as the difference between total binding and binding. , -7 does not specify that it was not displaced by 10 M of unlabeled LTB4. All data refers to specific binding. 19

Modified Bovden Chamber Ouimiotaxis

Human neutrophils were isolated from peripheral citrated blood using standard dextran sedimentation techniques, followed by centrifugation in sterile Histopaque (Sigma) or Ficoll-plate (Pharmacia) and hypotonic red blood cell lysis. A final cell suspension of 3.4 x 10 4 neutrophils / ml HEPES-buffered Hanks balanced saline (HBSS, pH 7.3) was added to the upper vessel (0.8 ml) of a modified Boyden chamber (vessel blind). The bottom vessel (0.2 ml), separated by a polycarbonate membrane (Nuleopore Corp.), contained HBSS or 3 X 10 M LTB4 in the presence or absence of the test compound. Following 90 minutes incubation at 37øC in 5% -95% air, cells from the lower vessel were lysed and the nuclei were counted on a Model S-Plus-IV Coulter Counter. Percent inhibition was calculated from cell counts corrected for occasional migration by subtracting the control HBSS mean. the compounds of this invention may be administered in various dosage forms. A preferred method of administration would be oral or in such a way as to localize the action of the inhibitor. In an inflammatory condition such as rheumatoid arthritis the compounds may be injected directly into the affected joint. The compounds may also be administered in unit dosage forms such as tablets, capsules, pills, powders or granules. They may be introduced intraperitoneally, subcutaneously, or intramuscularly using forms known in the pharmaceutical art. Topical application in the form of ointments and ointments is useful for the treatment of psoriasis. Regardless of the route of administration selected, the compounds are formulated into pharmaceutically acceptable dosage forms by standard methods known in the pharmaceutical art. 20

The results for reprehensible compounds of the invention are shown in Table 1.

The data are expressed as relative potency for compound 1 in Scheme 1, 7- [3, (4-acetyl-3-methoxy-2-propylphenoxy) propoxy] -3,4-dihydro-8-propyl-2H -1-benzopyran-2-carboxylic acid, which is shown generally in U.S. Patent No. 4,889,871.

Table 1

Values Relative Potency for LBT?

Connection to

Compound

Receiver LBT ^ Ouimiotaxis Descrranulation R Propyl

O-CNHS02 Ph 1.35 1.3 \ N-N 2-Propenyl \ 0.8 38

Cyclopropylmethyl \ N \ / W \ N 22.5 75

(1.8x10-6M) (1.5x10-SM) 1.0 (3.0x10-SM) 1.0 (3x10 " 7M)

The data are expressed as relative potency for a known LBT1 antagonist, compound 1 in Example 1, defined as 1.0. Values in parentheses refer to values Ι0ΓΛ50 for compound 1. IC50 is the effective concentration required to produce 50% inhibition.

The compounds of this invention may be administered in a series of dosage forms. A preferred method of administration will be orally or in order to localize the action of the antagonist. In an inflammatory condition such as rheumatoid arthritis, the compounds may be injected directly into the affected joint. The compounds may also be administered in unit dosage forms such as tablets, capsules, pills, powders or granules. They may be introduced intraperitoneally, subcutaneously, or intramuscularly using forms known in the pharmaceutical art. Topical application in the form of ointments or ointments is useful for the treatment of psoriasis. Regardless of the route of administration selected, the compounds are formulated into pharmaceutically acceptable dosage forms by conventional methods known in the pharmaceutical art.

In general, a unit dosage of a compound of the invention will contain from about 50 mg to about 500 mg of the active ingredient, preferably from about 70 mg to about 300 mg.

An amount of the effective but non-toxic compound is used in the treatment. The dosage regimen for LTB4 antagonism by the compounds of this invention is selected according to a number of factors including the type, age, sex, and clinical condition of the mammal, the particular disease and its severity, the route of administration, and the particular compound used. An experienced physician or veterinarian will rapidly determine and prescribe the effective amount of the compound, to prevent or disrupt the progression of the condition. Thus, the physician or veterinarian may use or use relatively low doses first, subsequently increasing the dose until a maximal response is obtained. Generally, a dose range of 1 to 25 mg / kg of body weight will be administered to patients in need of treatment of inflammatory conditions.

Claims (6)

24 1. A process for the preparation of a compound of the formula and their stereoisomers and pharmaceutically acceptable salts, wherein R represents lower alkyl of 1 to 6 carbon atoms, lower alkenyl of 2 to 6 carbon atoms, or - (CH 2) m R 3 in which R 2 represents cycloalkyl of 3 to 5 carbon atoms in is 1, 2 or 3: wherein R 2 is lower alkyl, phenyl, unsubstituted or substituted by lower alkyl; R 2 is -CONH 2 or -C? NHSO 2 R 2; or N-N and n is an integer from 2 to 5; 25-25 characterized in that: a) reacting a compound of the formula: with (C0Cl) 2 and NH3; or b) reacting a compound of the formula: with benzenesulfonamide; d) reacting a compound of the formula: 1 Τ * 1 Τ * with (COCl) 2 and NH 3; or e) reacting a compound of the formula: with (COCl) 2 and NH4; or g) reacting a compound of the formula: 3 'with NaN 22. A process as claimed in Claim 1, characterized in that R 1 is lower alkyl of 1 to 6 carbon atoms or - (CH 2) m R 3 in which R 3 represents cycloalkyl of 3 to 5 carbon atoms, carbon atom in is 1, 2 or 3; R 1 is -CONH, OR 11 -C-NHSO 2 R 2, wherein R 2 is phenyl, unsubstituted or substituted by lower alkyl; or N-N / 'fc V / n and n is 3, 4 or 5. 3a. A process according to Claim 2, characterized in that R 1 is propyl, 2-propenyl or cyclopropylmethyl; II is -CONH2 or -CNH2SO2; or - R2 is phenyl; and n is 3, 4 or 5. 4a. A process according to Claim 3, characterized in that a compound wherein R is 2-propenyl; R1 is and n is 3. 53. A process according to Claim 3, characterized in that a compound wherein R is cyclopropylmethyl; Ρχ is) and n is 3. 63. A process according to Claim 3, characterized in that a compound wherein R is propyl; R 2 is N and n is 3. 7a. A process according to Claim 3, characterized in that a compound in which R is propyl; R 2 is R 1 is -C-NHSO 2 R 2 wherein R 2 is phenyl; and n is 3. 8a. A process according to Claim 3, characterized in that a compound wherein R is cyclopropylmethyl; Rx is -CONH2; and n is 3. 9a. A process according to Claim 3, characterized in that a compound wherein R is 2-propenyl; Rx is -CONH2; and n is 3. 10a. A process for the preparation of a pharmaceutical composition for treating inflammatory diseases, characterized in that a therapeutically effective amount of a compound of the formula and their stereoisomers and pharmaceutically acceptable salts, wherein R represents lower alkyl of 1 to 6 carbon atoms, lower alkenyl of 2 to 6 carbon atoms, or - (CH 2) m R 3 wherein R 3 represents cycloalkyl of 3 to 5 atoms of carbon in is 1, 2 or 3; - * k * Ο ·. . wherein R 2 is lower alkyl, phenyl, unsubstituted or substituted with lower alkyl; or and n is an integer from 2 to 5, and a pharmaceutically acceptable carrier. III. A process according to Claim 10, characterized in that R 1 is lower alkyl of 1 to 6 carbon atoms or - (CH 2) m R 3 in which R 3 represents cycloalkyl of 3 to 5 carbon atoms in is 1, 2 or 3; II is -CONH2 or -CNHSO2 R2, wherein R2 is phenyl, unsubstituted or substituted by lower alkyl; or / and n is 3, 4 or 5. 12a. A process according to Claim 11, characterized in that a composition is prepared wherein R is propyl, 2-propenyl or cyclopropylmethyl; 31 - R 2 is -CONH 2 or -CNHSO 2 R 2; or R2 is phenyl; and n is 3, 4 or 5. 13a. A process according to Claim 12, characterized in that a composition is prepared wherein R 2 is 2-propoenyl; R1 is N and n is 3. 14a. A process according to Claim 12, characterized in that a composition is prepared wherein R is cyclopropylmethyl; R-is / N / e n is 3. 32: 3¾¾ * ν. 15a. A process according to Claim 12, characterized in that a composition is prepared wherein R is propyl; and and n is 3. A process according to Claim 12, characterized in that a composition is prepared wherein R is propyl; R 1 is wherein R 2 is phenyl; and n is 3. 17. A process according to Claim 12, characterized in that a composition is prepared wherein R is cyclopropylmethyl; R 2 is -CONH 2; and n is 3. 3. A process according to claim 12 for preparing a composition wherein R 2 is 2-propenyl; Rx is -conh2; and n is 3. Lisbon, December 17, 1991 J. PEREIRA DA CRUZ - Official Agent of Industrial Property RUA VtCTOR COROON, 10 · A 3. »1200 LISBOA