IE904233A1 - Pyridine-2,4- and 2,5-dicarboxamides, a process for the¹preparation thereof, and the use thereof - Google Patents

Abstract

The invention relates to pyridine-2,4- and 2,5-dicarboxylic acid diamides of the formula I in which R<1> has the meaning given. The compounds according to the invention inhibit the enzyme proline hydroxylase or lysine hydroxylase and can therefore be employed as fibrosuppressants and immunosuppressants.

Description

Description Pyridine-2,4- and 2,5-dicarboxamides, a process for the preparation thereof, and the use thereof Compounds which inhibit the enzymes proline hydroxylase and lysine hydroxylase bring about a very selective inhibition of collagen biosynthesis by influencing the collagen-specific hydroxylation reactions. In the course thereof, protein-bound proline or lysine is hydroxylated by the enzymes proline hydroxylase or lysine hydroxylase.

If this reaction is suppressed by inhibitors, the result is an insufficiently hydroxylated collagen molecule which is unable to function and can be released by the cells into the extracellular space only in a small amount.

Moreover, the insufficiently hydroxylated collagen cannot be incorporated in the collagen matrix and very readily undergoes proteolytic degradation. The consequence of these effects is an overall reduction in the amount of collagen deposited outside the cells.

It is known that the inhibition of proline hydroxylase by known inhibitors such as α, a'-dipyridyl results in inhibition of Clq biosynthesis by macrophages (W. Muller et al., FEBS Lett. 90 (1978), 218; Immunobiology 155 (1978), 47). This leads to the classical pathway of complement activation becoming inoperative. Thus, inhibitors of proline hydroxylase also act as immunosuppressants, for example in immune complex diseases.

It is known that the enzyme proline hydroxylase is efficiently inhibited by pyridine-2,4- and -2,5-dicarb30 oxylic acids (K. Ma jam a a et al., Eur. J. Biochem. 138 (1984) 239-245). These compounds are, however, effective inhibitors in cell culture only in very high concentrations (Tschank, G. et al., Biochem. J. 238 (1987) 625633) .

DE-A 34 32 094 gives a description of diesters of pyridine-2,4- and -2,5-dicarboxylic acids with 1-6 carbon atoms in the ester alkyl moiety as pharmaceuticals for inhibiting proline hydroxylase and lysine hydroxylase.

These lower alkyl diesters have the disadvantage, however, that in the body they are rapidly cleaved to the acids and do not reach their site of action in the cell in sufficiently high concentration and thus are poorly suited for possible administration as pharmaceuticals.

DE-A 37 03 959, DE-A 37 03 962 and DE-A 37 03 963 describe in a general form mixed ester/amides, higher alkyl diesters and diamides of pyridine-2,4- and -2,5-dicarboxylic acids, which are effective inhibitors of collagen biosynthesis in animal models.

Thus, DE-A 37 03 959 describes, inter alia, the synthesis of N,N'-bis (2-methoxyethy1)pyridine-2,4-dicarboxamide and N,N'-bis (3-isopropoxypropyl)pyridine-2,4-dicarboxamide.

German Patent Applications P 38 26 471.4 and P 38 28 140.6 propose an improved process for the preparation of N,N'-bis (2-methoxyethyl)pyridine-2,4-dicarboxamide .

German Patent Application P 3924093.2 proposes new N,N'bis(alkoxyalkyl)pyridine-2,4-dicarboxamides.

Both pyridine-2,4- and -2,5-dicarboxamides (Hirakata et al., J. pharm. Soc. Japan 77 (1957) 219 and Hiring et al., Helv. 37 (1954) 147, 153) and pyridine-2,4- and -2,5-dicarbohydrazides (Itai et al., Bl. nation, hyg. Labor. Tokyo, 74 (1956) 115, 117 and Shinohara et al., Chem. High Polymers Japan, 15 (1958) 839) have already been disclosed as agents for tuberculosis.

It has now been found, surprisingly, that substituted pyridine-2,4- and 2,5-dicarboxamides of the formula I R^HNOC(I) CONH-RJ in which is hydrogen or - N^R3 , where R2 and R3 are R identical or different and are hydrogen, Ci-C^-alkyl, phenyl or Ci-Ca-alkylcarbonyl, and the physiologically tolerated salts, are likewise effective inhibitors of lysine hydroxylase and proline hydroxylase in animal models.

Accordingly, the invention relates to a) compounds of the formula I the use of R1HNOC (I) in which R1 is hydrogen or - N\R3 , where R2 and R3 are identical or different and are hydrogen, Ci-C^-alkyl, phenyl or Ci-C3-alkylcarbonyl, and the physiologically tolerated salts, for the preparation of a pharmaceutical inhibiting proline hydroxylase and lysine hydroxylase.

The invention furthermore relates to b) the compounds of 20 the formula I in which R1 is - Νζ^3 t where R2 is hydrogen, Ci-C^-alkyl, ** Λ phenyl or C1-C3-alkylcarbonyl, and R has the meaning of R2 apart from hydrogen, and the physiologically tolerated salts, for use as pharmaceuticals.

The invention furthermore relates to c) the compounds of the formula I in which R2 R1 is - β , where R2 is hydrogen, C1-CA-alkyl, phenyl or C1-C3-alkylcarbonyl, and R has the meaning of R2 apart from hydrogen, and the physiologically tolerated salts thereof.

In particular, the invention relates to the compounds of the formula I defined in a), b) and c) for use as fibrosuppressants and immunosuppressants and for inhibiting proline hydroxylase and lysine hydroxylase and for influencing the metabolism of collagen and collagen-like substances and the biosynthesis of Clq.

All the said alkyl radicals with more than 2 carbon atoms can be both straight-chain and branched.

The invention furthermore relates to a process for the preparation of compounds of the formula I, which comprises reacting a compound of the formula II O N Y- cIi with a compound of the formula III H-N (HI) where R2 and R3 have the meanings specified for formula I, - 5 and Y is halogen, hydroxyl or C1-C4-alkoxy, or forms together with the carbonyl group an active ester or a mixed anhydride, or comprises first reacting the compound of the formula II in which Y is as defined above with a compound of the formula III in which R2=R3=H, and subsequently reacting the reaction product with a compound of the formula IV Y-C(O) -C1-C3-alkyl (IV) where Y is as defined above, and subsequently converting 10 the reaction products into the physiologically tolerated salts thereof where appropriate.

The preparation of compounds of the formula I and the preparation of those starting substances required for this which cannot be bought is described in detail hereinafter.

The compounds according to the invention are prepared most straightforwardly by the two components, the pyridine derivative of the formula (II) and the amine of the formula (III), being mixed in equimolar amounts or with an up to about 5-fold excess of III and reacted at temperatures between -30 and 150°C, preferably at 20 to 100°C, until the reaction is complete. The completion of the reaction can be determined, for example, by thinlayer chromatography. One variant of this process com25 prises using a suitable solvent such as diethyl ether or dimethoxyethane or tetrahydrofuran, chlorinated hydrocarbons such as methylene chloride, chloroform, tri- or tetrachloroethylene, benzene, toluene or else polar solvents such as dimethylformamide, acetone, alcohols such as methanol or ethanol or dimethyl sulfoxide. It is also possible in this case to use an excess of amine of the formula (III), which can be up to about 5-fold amounts. The temperatures for this reaction are between room temperature and the boiling point of the solvent, with temperatures in the range from room temperature to - 6 130°C being particularly preferred.

The reaction can likewise be carried out via a mixed anhydride such as ethyl chloroformate or via an activated ester such as paranitrophenyl ester (Y= C1CH2-COO or NO2-C6H<,-O) . Appropriate methods are described in the literature.

It is also possible, where appropriate, for the reaction to be carried out in the presence of bases. Examples of suitable additional bases are carbonates or bicarbonates such as sodium or potassium carbonate or sodium or potassium bicarbonate, or tertiary amines such as triethylamine, tributylamine, ethyldiisopropylamine or heterocyclic amines such as N-alkylmorpholine, pyridine, quinoline or dialkylanilines.

One variant for the preparation of the compounds with R2=Cj-C3-alkylcarbonyl comprises componds with R2=R3=H being prepared as described above and then mixed with Ci-Ca-alkanoyl chlorides in equimolar amounts or with an up to about 5-fold excess of acid chloride, and reacted at temperatures between -30° and 150*C, preferably at 20° to 100°C, until the reaction is complete. It is also possible to use a suitable solvent such as dimethylformamide, acetone, alcohols such as methanol or ethanol or dimethyl sulfoxide. The reaction can also, where approp25 riate, be carried out in the presence of bases. Examples of suitable additional bases are carbonates or bicarbonates such as sodium or potassium carbonate or sodium or potassium bicarbonate, or tertiary amines such as triethylamine, tributylamine, ethyldiisopropylamine or heterocyclic amines such as N-alkylmorpholine, pyridine, quinoline or dialkylanilines.

Where appropriate the products can be worked up, for example, by extraction or by chromatography, for example on silica gel. The isolated product can be recrystallized and, where appropriate, reacted with a suitable acid to - Ί give a physiologically tolerated salt. Examples of suitable acids are: mineral acids such as hydrochloric and hydrobromic acid, and sulfuric, phosphoric, nitric or perchloric acid or organic acids such as formic, acetic, propionic, succinic, glycolic, lactic, malic, tartaric, citric, maleic, fumaric, phenylacetic, benzoic, methanesulfonic, toluenesulfonic, oxalic, 4-aminobenzoic, naphthalene-1,5-disulfonic or ascorbic acid.

Those starting compounds of the formula (HI) which cannot be bought can be synthesized by processes known from the literature.

The starting compounds of the formula (II) are obtained, for example, by converting pyridine-2,4- or 2,5-dicarb15 oxylic acid into the corresponding pyridine-2,4- or 2,5dicarbonyl halide, preferably chloride (by processes known from the literature), preferably in the presence of a catalyst such as dimethylformamide. This acid halide can then be reacted, for example, either with a suitable alcohol, for example paranitrobenzyl alcohol, to give the corresponding active ester, or else with lower alcohols such as methanol or ethanol to give the corresponding esters. It is likewise also possible for the pyridine2,4- or 2,5-dicarboxylic acid initially to be converted by addition of a suitable carboxylic acid or of a carboxylic ester such as ethyl chloroformate into a mixed anhydride which is then reacted with the amines (III) to give the products according to the invention. An appropriate method is likewise described in the literature.

The compounds of the formula I according to the invention have valuable pharmacological properties and display, in particular, activity as inhibitors of proline hydroxylase and lysine hydroxylase, as fibrosuppressant and immunosuppressant. - β Because of these pharmacological properties, the compounds according to the invention are suitable for the treatment of disturbances of the metabolism of collagen and collagen-like substances and for the treatment of disturbances of the biosynthesis of Clq.

Hence the invention furthermore relates to the use of the compounds of the formula I according to the invention and of the physiologically tolerated salts thereof for the treatment of the abovementioned metabolic disorders.

The compounds can be used as pharmaceuticals either alone or mixed with physiologically tolerated auxiliaries or excipients. They can be administered for this purpose orally in doses of 0.01 - 25.0 mg/kg/day, preferably 0.01 - 5.0 mg/kg/day or parenterally in doses of 0.001 - 5 mg/ kg/day, preferably 0.001 - 2.5 mg/kg/day, in particular 0.005 - 1.0 mg/kg/day. The dose can also be increased in severe cases. However, in many cases, lower doses are also sufficient. These data relate to adults weighing about 75 kg.

The invention additionally embraces the use of the compounds according to the invention for the preparation of pharmaceuticals which are employed for the treatment and prophylaxis of the abovementioned metabolic disorders .

The invention furthermore relates to pharmaceuticals which contain one or more compounds of the formula I according to the invention and/or the physiologically tolerated salts thereof.

The pharmaceuticals are prepared by processes which are known per se and familiar to those skilled in the art.

The pharmacologically active compounds (= active substance) according to the invention are employed as pharmaceuticals either as such or, preferably, in combination with suitable pharmaceutical auxiliaries or - 9 excipients in the form of tablets, coated tablets, capsules, suppositories, emulsions, suspensions or solutions, in which the content of active substance is up to about 95%, preferably between 10 and 75%.

Examples of suitable auxiliaries or excipients for the desired pharmaceutical formulation are, besides solvents, gel-formers, suppository bases, tablet auxiliaries and other active substance vehicles, also antioxidants, dispersing agents, emulsifiers, antifoam agents, flavor correctives, preservatives, solubilizers and colorants.

The active substances can be administered orally, parenterally or rectally.

The active compounds are mixed with the additives suitable for this purpose, such as excipients, stabilizers or inert diluents, and converted by customary methods into suitable dosage forms such as tablets, coated tablets, hard gelatin capsules, aqueous, alcoholic or oily suspensions or aqueous or oily solutions.

Examples of inert excipients which can be used are gum arabic, magnesia, magnesium carbonate, potassium phosphate, lactose, glucose or starch, especially corn starch. This preparation can be carried out both as dry and as wet granules. Examples of suitable oily excipients or solvents are vegetable or animal oils, such as sun25 flower oil or fish liver oil.

For subcutaneous or intravenous administration, the active compounds are converted into solution, suspension or emulsion, if desired with the substances suitable for this purpose, such as solubilizers, emulsifiers or other auxiliaries. Examples of suitable solvents are physiological saline or alcohols, for example ethanol, propanol, glycerol, as well as sugar solutions such as glucose or mannitol solutions, or else a mixture of the various solvents mentioned. - 10 The invention is explained in detail hereinafter by means of examples .

Example 1: 2.4- Bis (2-acetylhydrazinocarbonyl)pyridine (Formula I: R1 = NH-C(O)CH3) 12.6 g of pyridine-2,4-dicarbohydrazide are suspended in 750 ml of diohloromethane. To this are added at room temperature 7.9 g of Ν,Ν-dimethylaminopyridine and 32.4 ml of acetic anhydride.

The mixture is stirred at this temperature for 36 h, concentrated and evaporated 3 times with toluene. The residue is chromatographed on silica gel (mobile phase: cyclohexane/ethyl acetate 1/4).

Yield: 5.6 g Melting point: 136-137°C Example 2: 2.5- Bis(2-methylhydrazinocarbonyl)pyridine (Formula I: R1 = NH-CH3) Dimethyl pyridine-2,5-dicarboxylate are dissolved in 100 ml of methanol, and 0.5 g of methylhydrazine is added. The mixture is stirred under reflux for 4 hours and concentrated, and the residue is stirred with diisopropyl ether and filtered off with suction.

Yield: 0.75 g Melting point: 202°C Example 3: Pharmacological activity To demonstrate the efficient inhibition of proline hydroxylase and lysine hydroxylase by the compounds - 11 according to the invention, the hydroxyproline concentrations in the liver and the procollagen III peptide concentrations in the serum of a) untreated rats (control) b) rats given tetrachloromethane (CC14 control) c) rats given first CC14 and then a compound according to the invention were measured (this test method is described by Rouiller, C., experimental toxic injury of the liver; in The Liver, C. Rouiller, Vol. 2, pages 335-476, New York, Academic Press, 1964) .

The potency of the compounds according to the invention was determined as the percentage inhibition of liver hydroxyproline and procollagen III peptide synthesis after oral administration compared with control animals which were given only tetrachloromethane (CC14 control). The results are listed in Table 1.

Table 1: Effect of prolyl hydroxylase inhibitors on CC1Ainduced liver fibrosis in rats, 8-week treatment Compound Dose® mg/kg N Bilirubin13 μΜ PIIIP0 ng/ml Hypd Mg/ml Control 20 1.9 11 0.056 CC14 56 4.5 32 0.228 Increase 36 2.6 21 0.172 Diamide 50 20 3.1 25 0.163 Increase® 1.2 14 0.107 Decreasef 54 35 38 % Mean8 (42 ± 6 %) Example 1 50 16 3.0 29 0.181 Increase® 1.1 18 0.125 Decrease* 58 14 27 % Mean8 (33 ± 13 %) a: daily oral dose b: bilirubin in serum (total) cs procollagen III N-peptide in serum d: hydroxyproline content in the liver e: increase (absolute) compared with control f: percentage decrease compared with CC14 treatment g: total content of bilirubin, PIIIP and Hyp, % deviation

Claims (21)

1. Patent Claims HOE 89/F 369 - 13 1. The use of pyridine-2,4- and 2,5-dicarboxamides of the formula I R -HNOC. 'exC0NH-R J (I) in which where R 2 and R 3 are R is hydrogen or - t identical or different and are hydrogen, Cx-Ct-alkyl, phenyl or Ci-^-alkylcarbonyl, and the physiologically tolerated salts, for the preparation of pharmaceuticals inhibiting proline hydroxylase and lysine hydroxylase.

2. The use as claimed in claim 1, wherein R 1 is hydrogen or amino which is unsubstituted or monosubstituted by Ci-Ca-alkyl, phenyl or Ci-Cs-alkylcarbonyl.

3. The use as claimed in claim 1, wherein R 1 is hydrogen or amino which is unsubstituted or monosubstituted by acetyl.

4. A compound of the formula I R 1 HNOC--XK (I) — CONH- R 1 in which 1 -X> 2 R is - , where R is hydrogen, Ci-C^-alkyl, phenyl or C 1 -C 3 -alkylcarbonyl, and R has the meaning of R 2 apart from hydrogen, - 14 and the physiologically tolerated salts, for use as pharmaceutical.

5. A compound of the formula I as claimed in claim 4 for use as pharmaceutical, wherein R 2 is hydrogen, and R 3 is C 2 -C 4 -alkyl, phenyl or C 1 -C 2 -alkylcarbonyl.

6. . A compound of the formula I as claimed in claim 4 or 5, wherein R 2 is hydrogen, and R 3 is C 3 -C 4 -alkyl or acetyl.

7. A compound of the formula I R^HNOC- (I) CONH-R 1 in which . _ μ 2 R is - 3 , where R is hydrogen, Ci-C^-alkyl, phenyl or Cj-Ca-alkylcarbonyl, and R 3 has the meaning of R 2 apart from hydrogen, and the physiologically tolerated salts thereof.

8. A compound of the formula I as claimed in claim 7, wherein R 2 is hydrogen, and R 3 is Cj-C 2 -alkyl, phenyl or C 1 -C 2 -alkylcarbonyl.

9. . A compound of the formula I as claimed in claim 7 or 8, wherein R 2 is hydrogen, and R 3 is C 3 -C 4 -alkyl or acetyl.

10. A process for the preparation of compounds of the formula I as claimed in claim 7, which comprises reacting a compound of the formula II II with a compound of the formula III H-N (III) where R 2 and R 3 have the meanings specified for formula I in claim 7, and Y is halogen, hydroxyl or Ci-C^-alkoxy, or forms together with the carbonyl group an active ester or a mixed anhydride, or comprises first reacting the compound of the formula II in which Y is as defined above with a compound of the formula III in which R 2 =R 3 =H, and subsequently reacting the reaction product with a compound of the formula IV Y-C(O) -Ci-Ca-alkyl (IV) where Y is as defined above, and subsequently converting the reaction products into the physiologically tolerated salts thereof where appropriate.

11. A compound as claimed in one or more of claims 7 to 9 for use as pharmaceutical.

12. A compound as claimed in one or more of claims 4 to 9 for inhibiting proline hydroxylase and lysine hydroxylase.

13. A compound as claimed in one or more of claims 4 to 9 for use as fibrosuppressant and immunosuppressant.

14. A pharmaceutical containing a compound of the formula I as claimed in one or more of claims 4 to 9 with tolerated pharmaceutical vehicles.

15. The use of compounds of the formula I as claimed in one or more of claims 1 to 9 for influencing the metabolism of collagen and collagen-like substances and the biosynthesis of Clq.

16. The use of compounds of the formula I as claimed in - 1ό one or more of claims 1 to 9 for the treatment of disturbances of the metabolism of collagen and collagenlike substances and of the biosynthesis of Clq.

17. . A process for the preparation of pharmaceuticals for influencing the metabolism of collagen and collagen-like substances and of the biosynthesis of Clq, which comprises incorporating a compound of the formula I as claimed in one or more of claims 1 to 9 into the pharmaceutical.

18. A compound as claimed in claim 7, substantially as hereinbefore described and exemplified.

19. A process for the preparation of a compound as claimed in claim 7, substantially as hereinbefore described and exemplified.

20. A compound as claimed in claim 7, whenever prepared by a process claimed in claim 10 or 19.

21. A pharmaceutical as claimed in claim 14, substantially as hereinbefore described.