DE4117802A1 - New 2-amino-pyridin-3-carbo:nitrile derivs. - used for treatment of human cytomegalovirus - Google Patents

Abstract

2-Amino-3-cyano-pyridine derivs. of formula (I) are new: In (I) R1 = H, 1-4C alkyl, mono- or polycycloalkyl, cycloalkenyl, phenylalkyl, alkoxyphenylalkyl, aryl, halophenyl, alkylphenyl, trifluoromethylphenyl, cycloalkyl-phenyl, a heterocyclic residue (contg. O or S as ring atom) or phenyl substd. by a heterocyclic substit. (contg. N and opt. O); R2 = H, 1-4C alkyl, phenylalkyl or aryl; R3 = H, 1-4C alkyl or aryl; or R1+R2 or R2+R3 = (CH2)n (opt. substd. by 1-4C alkyl, phenyl or a ketal gp) or a benzofused alkylene bridge of formula (i): n = 3,4,5,6,10 or 13; m = 1,2 or 3. USE - (I) are selective inhibitors of human cytomegalovirus.

Description

The invention relates to 2-aminopyridine-3-carbonitrile as selective inhibitors of human cytomegalovirus (HCMV), simple processes for their preparation and their use as active ingredients for drugs used to treat HCMV Infections can be used.

From the prior art there is a variety of under differently substituted 2-aminopyridine-3-carbonitriles knows, of which some representatives pharmacological, in particular their cancerostatic / R. Balicki, P. Nantka-Namirski: Pol. J. Chem. 56, 1125 (1982) / and positive inotropic / E. Klauschenz, V. Hagen, A. Hagen, S. Heer: Pharmazie 45, 628 (1990) /, and bactericidal, fungicidal and insecticidal / E. Poetsch: DE-OS 18 11 973, Chem. Abstr. 73: 55978 (1970); J.E.D. Barton, P.F.H. Freeman: DE-OS 20 29 079, Chem. Abstr. 74, 99891 d (1971); P.F.H. Freeman: US 36 74 877, Chem. Abstr, 77, 88314 d (1972); N. Latif, N. Mishriky, N. D. Girgis: Indian J. Chem. 20B, 147 (1981); N. Latif, F. M. Asaad, N. S. Girgis: Indian. J. Chem. 20B, 463 (1981); A. Attia, M. Michael: Pharmacy 37, 551 (1982); A. Attia, M. Michael: Acta Chim. Acad. Sci. Hung. 112, 89 (1983); K.M. Ghoneim, M.M. Badran, M.A. Shaaban, S. El- Meligie: Egypt J. Pharm. Sci. 29, 563 (1988), Chem. Abstr. 111, 7161x (1989); L. Prakash, M. S. Shaihla, R. L. Mital: Curr. Sci. 58: 967 (1989) Chem. Abstr. 112, 158014 y (1990) / effectiveness have. Antiviral activity is 2-aminopyridine 3-carbonitrile has not yet been described.

In addition to a number of very limited synthetic methods the and such procedures, which become representatives with a he lead to non-relevant substituent patterns the 2-aminopyridine-3-carbonitriles in general by Um setting of N.N-disubstituted 5-amino-2-cyanpenta-2.4-diene nitriles / H. Kurihara, H. Mishima: J. Heterocycl. Chem. 14, 1077 (1977); G. Ege, H. O. Frey, E. Schuck: Synthesis 376  (1979); R. D. Acker, G. Hamprecht: DE-OS 31 03 065, Chem. Abstr. 97, 182224j (1982); J.L. Miesel: US 45 08 722, Chem. Abstr. 98, 71937 v (1983); V. G. Granik, N.I. Smetskaya, N.A. Mukhina, I.V. Persianova, V.G. Klimenko: Khim, Geterotsikl. Soedin. 1279 (1983); N.I. Smetskaya, N.A. Mukhina, V.G. Granik: Khim. Heterotics Soedin. 799 (1984); J.I. DeGraw, H. Tagawa, P. H. Christie, J. A. Lawson, E. G. Brown, R. L. Kislink, Y. Gau mont: J. Heterocycl. Chem. 23: 1 (1986); V. Hagen, A. Rumler, H. Niedrich, D. Lohmann, H.-J. Jansch, G. Faust, H.J. Heidrich: DD 263.758, Chem. Abstr. 111, 134006 a (1989) /, 5-hydroxy-2- cyanpenta-2,4-diene nitriles / A. Dornow, E. New Zealand: Arch. Pharm. 288, 174 (1955) / 5-alkoxy-2-cyanpenta-2.4-diene nitriles / E. C. Taylor, A. McKillop, The Chemistry of Cyclic Enaminonitriles and o-Aminonitriles, Interscience Publishers, New York, London, Sydney, Toronto 1970, p. 169; B. W. Dominy M. J. Abu el-Haj: DE-AS 23 65 302, Chem. Abstr. 81, 49575 a (1974); M. J. Abu el-Haj, B. W. Dominy: US 39 62 264, Chem. Abstr. 85, 123967 h (1976) / or 2-chloropyridine-3-carbonitriles / M. Abdalla, A. Essawy, A. Deeb: Pak. J. Sci. Ind. Res. 20, 139 (1977), Chem. Abstr. 90, 137633 m (1979); J.L. Miesel: US 45 08 722, Chem. Abstr. 98, 71937 v (1983); E. Klauschenz, V. Hagen, A. Hagen, S. Heer: Pharmazie 45, 628 (1990) / with Am manufactured moniak. This generally reaction lasting several hours time-consuming procedures sometimes have a number other disadvantages, such as difficult accessibility the required raw materials and the need working under increased pressure.

Human cytomegalovirus infections are a common Complication after organ transplantation. From the standing it is known in the art that chemotherapy from HCMV-Infek tions essentially only through the use of the active ingredient Gancyclovir, a virustatic with specific activity against HCMV containing patenterals can be made. The well-known spectrum of side effects of Gancyclovir, which is known as teratogenic and potentially carcinogenic thereby considerably impairs its broad clinical applicability speed. In patients with the pronounced myelosuppressive acting Gancyclovir can be treated, the clinical  Symptoms of leukopenia and thrombopenia are observed. Also dermal, renal, gastrointestinal and the heart circle Side effects of gancyclovir that affect the running system known.

The object of the present invention is to create new selective In human cytomegalovirus hibitors and simple procedures to develop for their synthesis.

According to the invention, this object is achieved in that 2-amino pyridine-3-carbonitriles of the general formula I,

wherein

R¹ is hydrogen, lower alkyl (C₁-C₄), mono- or polycycloalkyl, cycloalkenyl, phenylalkyl, alkoxyphenylalkyl, aryl, halophenyl, alkylphenyl, trifluoromethylphenyl, cycloalkylphenyl, a heterocyclic substituent containing nitrogen or nitrogen and oxygen as the ring atom or phenyl radical or an oxygen or heterocyclic radical containing sulfur as ring atom,
R² is hydrogen, lower alkyl (C₁-C₄), phenylalkyl or aryl,
R³ is hydrogen, lower alkyl (C₁-C₄) or aryl
mean or
R¹R² together respectively
R²R³ together is an alkylene bridge or an alkylene bridge substituted by lower alkyl (C₁-C₄), phenyl or a ketal group in the meaning of - (CH₂) _n - with n = 3, 4, 5, 6, 10 and 13 or a benzo-fused alkylene bridge in the meaning of

with m = 1, 2 and 3 represent, are produced by reacting 5-amino 2-cyanpenta-2,4-diene nitriles of the general formula II

with those for R¹, R² and R³ or R¹R² and R²R³ given explanation and in the R⁴ and R⁵ Nierigalkyl (C₁-C₄), Cycloalkyl, benzyl or phenyl or R⁴R⁵N together Pyrrolidin-1-yl, piperidino, perhydroazepin-1-yl, morpholino or 4-methylpiperazin-1-yl mean with ammonia, the Reaction under normal pressure in a mixture of water and an organic solvent, optionally briefly early heating is carried out. Ammonia gets in shape commercial concentrated aqueous solution used. An organic solvent is a water-miscible alcohol, such as methanol, ethanol, n- or iso- Propanol, a water-miscible ether, such as 1,2-dimethoxyethane, tetrahydrofuran or dioxane, acetonitrile, Dimethyl sulfoxide or a water-miscible carboxylic acid amide such as formamide, N.N-dimethylformamide or N.N-diethylacetamide, for use.

Another possibility for the solution according to the invention is that 2-aminopyridine-3-carbonitrile of all general formula I can be prepared by 5-amino 2-cyanpenta-2,4-diene nitriles of the general formula III

with those for R¹, R² and R³ or R¹R² and R²R³ explanation given in an organic solvent in counter were or the absence of a basic catalyst for a short time warmed up. As a basic catalyst, an alkali hydroxide, such as sodium or potassium hydroxide, or an alcohol  holate, such as sodium methylate or ethylate or Potassium tert-butoxide used. As an organic solution an alcohol, such as methanol, ethanol, n- or iso-propanol, n-, sec- or iso-butanol, a glycol, such as ethylene glycol, a glycol ether such as Bei play ethylene glycol diethyl ether, acetonitrile, a nitroalkane, such as nitromethane or ethane, or a carbon acid amide, such as formamide, N.N-dimethylformamide, N.N-diethylacetamide or 1-methylpyrrolidone. The teaching of the invention allows the 2-aminopyridine 3-carbonitriles of the general formula I in a simple manner, in short response times and under normal pressure with only one Process step and without complex separation operations make accessible, easy to manufacture output connection be used.

The products of the general formula I according to the invention are for the most part new. Already known, on comparison cash or other way synthesized compounds of all general formula I can with the help of Ver drive easier and especially made at normal pressure become, which in some cases completely contradicts the be known prior art.

The antiviral efficacy found is surprising Products of the general formula I, since from the state of the Tech nik of 2-aminopyridine-3-carbonitriles so far only kanzerosta tables, positively inotropic as well as bactericidal, fungicidal and in secticidal effects are known.

With regard to the antiviral spectrum of the most effective Vertre ter of the products of general formula I is the specific one Inhibition of human cytomegalovirus remarkable while for example the herpes simplex virus 1 (HSV-1) and that Herpes simplex virus 2 (HSV-2) also with test substance concentrate ions of 100 µmol / l are not inhibited. So under these representatives differ fundamentally in their effect Gancyclovir, which is already at concentrations of only 1 µmol / l significantly inhibits both HSV-1 and HSV-2. Also against other types of virus, such as hepatitis B virus and type A influenza viruses show that particularly  effective representatives of the products of general formula I. no inhibitory effect.

The selectivity found is of particular importance Inhibition of the human cytomegalovirus by the products of general formula I what the high therapeutic indices (up to about 800) some representatives compared to Gancyclovir (therapeutic index = 9600) clearly prove.

The inventive method thus 2-amino pyridine-3-carbonitriles of the general formula I accessible made as selective inhibitors of human cytomega lievirus are in principle suitable as active ingredients for Medicines used for chemotherapy of HCMV infections to become.

Embodiments Example 1

The 2-amino produced according to the different variants pyridine-3-carbonitriles of the general formula I are in Ta belle 1 summarized.

option A

To a suspension of 10 mmol 5-amino-2-cyanpenta-2.4-diene nitrile of the general formula II (R⁴R⁵N = morpholino) in the The amount of acetonitrile given in Table 1 is left at room temperature with stirring 100 mmol concentrated aqueous ammo Drop niac solution. The initial connection then dissolves gradually, while at the same time precipitating the end product len begins. After stirring for a total of two hours, the mixture is sucked the end product of the general formula I, washed with water and iso-propanol, air-dry and crystallize optionally from the solvent specified in Table 1 around.

Variant B

Analogous to A, but the implementation of 5-amino-2-cyan penta-2.4-diene nitrile of the general formula II (R⁴R⁵N =  Pyrrolidin-1-yl) with ammonia in the given in Table 1 NEN amount of methanol performed.

Variant C

Analogous to A, but the conversion of 10 mmol 5-amino 2-cyanpenta-2,4-diene nitrile of the general formula II (R⁴R⁵N = Morpholino) using 200 mmol concentrated aq ammonia solution in the amount specified in Table 1 N.N-dimethylformamide performed.

Variant D

Analogous to C, but using 10 mmol 5-amino-2-cyan penta-2.4-diennitrile of the general formula II (R⁴ = CH₃, R⁵ = C₆H₅).

Variant E

A suspension of 10 mmol 5-amino-2-cyanpenta-2,4-diennitrile of the general formula II (R⁴R⁴N = pyrrolidin-1-yl) in one Mixture of 100 mmol concentrated aqueous ammonia solution and the amount of N.N-dimethylformamide shown in Table 1 with stirring until the dissolution of the Aus heated connection. With further stirring, the Cool the solution slowly again, gradually increasing the end product Lich crystallized. The end product of the general formula I becomes, as described A, after a total of about two hours the reaction time isolated and cleaned.

Variant F

Analogous to E, but the implementation of 5-amino-2-cyan penta-2.4-diene nitrile of the general formula II (R⁴R⁵N = Piperidino) with ammonia in the amount given in Table 1 Ethanol performed.

Variant G

Analogous to E, but the implementation of 5-amino-2-cyan penta-2.4-diene nitrile of the general formula II (R⁴ = R⁵ = CH₃) with ammonia in the amount of dime specified in Table 1 carried out thylsulfoxide.

Variant H

Analogous to H, but instead of dimethyl sulfoxide, the in Table 1 specified amount of N.N-diethylacetamide used.  

Variant I

Analogous to E, but using 10 mmol 5-amino-2-cyan penta-2.4-diennitrile of the general formula II (R⁴ = CH₃, R⁵ = C₆H₅).

Variant J

Analogous to E, but using 10 mmol 5-amino-2-cyan penta-2.4-diennitrile of the general formula II (R⁴ = CH₃, R⁵ = Cyclohexyl).

Variant K

Analogous to E, but using 10 mmol 5-amino-2-cyan penta-2.4-diennitrile of the general formula II (R⁴ = CH₃, R⁵ = C₆H₅CH₂).

Variant L

Analogous to E, but the implementation of 5-amino-2-cyanopenta- 2.4-diene nitrile of the general formula II (R⁴ = R⁵ = C₆H₅) with Ammonia in the amount of formamide given in Table 1 guided.

Variant M

Analogous to E, but the implementation of 5-amino-2-cyanopenta- 2.4-diene nitrile of the general formula II (R⁴R⁵N = 4-methyl piperazin-1-yl) with ammonia in that specified in Table 1 Amount of 1,2-dimethoxyethane performed.

Variants

Analogous to E, but the implementation of 5-amino-2-cyanopenta- 2.4-diene nitrile of the general formula II (R⁴R⁵N = perhydro azepin-1-yl) with ammonia in the table Amount of tetrahydrofuran performed.

Variant O

Analogous to E, but the conversion of 10 mmol 5-amino-2- cyanpenta-2,4-diene nitrile of the general formula II (R⁴ = CH₃, R⁵ = C₆H₅) using 200 mmol concentrated aq ammonia solution.

Variant P

A mixture of 10 mmol 5-amino-2-cyanpenta-2,4-diene nitrile of the general formula II (R⁴ = C₂H₅, R⁵ = C₆H₅), 200 mmol  concentrated aqueous ammonia solution and that in Table 1 specified amount of dioxane is refluxed for 30 minutes cooks. After cooling, the final product becomes the general Formula I, as described for A, isolated and purified.

Variant Q

Analogous to P, but the implementation of 5-amino-2-cyanopenta- 2.4-diene nitrile of the general formula II (R⁴ = CH₃, R⁵ = C₆H₅) with ammonia in the amount iso-Pro given in Table 1 carried out panol.

Variant R

Analogous to P, but the implementation of 5-amino-2-cyanopenta- 2.4-diene nitrile of the general formula II (R⁴R⁵N = morpholino) with ammonia in the amount of ethanol specified in Table 1 carried out.

Variant S

A mixture of 10 mmol of 5-amino-2-cyanpenta-2,4-dienitrile general formula III, the amount given in Table 1 Methanol and 1 drop of 0.1 N aqueous sodium hydroxide solution is used until Boiling heated. The crystallizing after cooling The end product of the general formula I is as described for A. ben, isolated and cleaned.

Variant T

Analogous to S, but the implementation is shown in Table 1 given amount of ethylene glycol diethyl ether.

Variant U

Analogous to S, but the implementation is shown in Table 1 given amount of ethanol with the addition of 1 drop of an ethane Oleic solution of sodium ethylate instead of sodium hydroxide solution carried out.

Variant V

Analogous to S, but the implementation is shown in Table 1 given amount of n-butanol with the addition of 5 mg of potassium tert. performed butylate instead of sodium hydroxide solution.

Variant W

A mixture of 10 mmol 5-amino-2-cyanpenta-2,4-diennitrile  general formula III and the amount given in Table 1 Nitroethane is heated until boiling begins. That after the Ab cool crystallizing end product of the general formula I is suction filtered, washed with ethanol and, as described for A ben, cleaned.

Variant X

Analogous to W, but the implementation is shown in Table 1 given amount of formamide performed.

Variant Y

Analogous to W, but the implementation is shown in Table 1 given amount of 1-methylpyrrolidone performed.

Variant Z

Analogous to W, but the implementation is shown in Table 1 given amount of ethylene glycol.

Example 2

The testing of 2-aminopyridine-3-carbonitriles of the general Formula I on HCMV inhibitory activity was carried out with the help a modified form of the plaque reduction test according to B. Wentworth and K. French / Proc. Soc. Exp. Biol. Med. 135, 253 (1970) / on a cell lawn from semi-confluent human em bryonal pulmonary fibroblasts (HELF Fi 296). From the get A dose-response curve was the concentration of each Substance of the general formula I taken, which is a 50 percent reduction in the number of plaques compared to an unsteady one delten virus control culture causes (ID₅₀ value).

To assess the cyclotoxic properties, the Ein flow of substances of general formula I on the cell pro liferation determined using a modified MTT test. The concentration that is a 50 percent inhibition of proliferation was caused from the ratio of optical density between treated virus culture and untreated virus control culture determined (CD₅₀ value).

The test results (ID₅₀ value and therapeutic index TI = CD₅₀ / ID₅₀) are summarized in Table 2.

Table 2

Inhibitory activity of compounds of general formula I (R³ = H) against human cytomegalovirus (HCMV) in comparison to gancyclovir (ID₅₀ = 0.25 µmol / l; TI = CD₅₀ / ID₅₀ = 9600) as standard

Claims (9)

1. Compounds of the general formula I, wherein
R¹ is hydrogen, lower alkyl (C₁-C₄), mono- or polycycloalkyl, cycloalkenyl, phenylalkyl, alkoxyphenylalkyl, aryl, halophenyl, alkylphenyl, trifluoromethylphenyl, cycloalkylphenyl, a phenyl radical containing a nitrogen or nitrogen and oxygen as ring atom or a phenyl radical or an oxygen or Heterocyclic radical containing sulfur as ring atom,
R² is hydrogen, lower alkyl (C₁-C₄), phenylalkyl or aryl,
R³ is hydrogen, lower alkyl (C₁-C₄) or aryl
mean or
R¹R² together respectively
R²R³ together is an alkylene bridge or an alkylene bridge substituted by lower alkyl (C₁-C₄), phenyl or a ketal group in the meaning of - (CH₂) _n - with n = 3, 4, 5, 6, 10 and 13 or a benzo-fused alkylene bridge in the meaning of with m = 1, 2, and 3. 2. A process for the preparation of the compounds according to claim 1 by reacting 5-amino-2-cyanpenta-2,4-dienonitriles of the general formula II with the explanation given for R¹, R² and R³ or R¹R² and R²R³ and in which R⁴ and R⁵ lower alkyl (C₁-C₄), cycloalkyl, benzyl or phenyl or R⁴R⁵N together pyrrolidin-1-yl, piperidino, perhydro azepin-1-yl, Morpholino or 4-methylpiperazin-1-yl mean with ammonia, characterized in that the reaction is carried out under normal pressure in a mixture of water and an organic solvent, if appropriate with brief heating. 3. The method according to claim 2, characterized in that Ammonia in the form of commercially available concentrated aqueous Solution is used. 4. The method according to claim 2, characterized in that as an organic solvent a miscible with water Alcohol such as methanol, ethanol, n- or iso-propanol, a water-miscible ether such as Example 1.2-dimethoxyethane, tetrahydrofuran or dioxane, Acetonitrile, dimethyl sulfoxide or a mixture with water hard carboxamide, such as formamide, N.N- Dimethylformamide or N.N-diethylacetamide is used. 5. A process for the preparation of the compounds according to claim 1, characterized in that 5-amino-2-cyanpenta-2.4- diennitrile of the general formula III briefly heated with the explanation given for R¹, R² and R³ or R¹R² and R²R³ in an organic solvent in the presence or absence of a basic catalyst. 6. The method according to claim 5, characterized in that as a basic catalyst, an alkali metal hydroxide, such as Example sodium or potassium hydroxide, or an alcoholate, such as sodium methylate or ethylate or Potassium tert-butoxide is used. 7. The method according to claim 5, characterized in that an alcohol as organic solvent, such as play methanol, ethanol, n- or iso-propanol, n-, sec.- or iso-butanol, a glycol, such as ethylene glycol, a glycol ether such as ethylene glycol diethyl ether, acetonitrile, a nitroalkane, as for example play nitromethane or ethane, or a carboxamide, such as formamide, N.N-dimethylformamide, N.N- Diethylacetamide or 1-methylpyrrolidone is used. 8. Use of the compound according to claim 1 as an inhibitor substances of the human cytomegalovirus. 9. Use of the compounds according to claim 1 as active substances for medicinal products for the treatment of human Infections caused by cytomegalovirus.