DE2621470A1 - Nucleoside carboxylic acid nitriles and derivs. - prepd. from a (5')-(O)-tosylated or halogenated nucleoside and a metal cyanide or alpha:alkali acetic acid - Google Patents

Abstract

New nucleoside carboxylic acid nitriles and their derivs. are of formula (I). (In (I) R is H or OH; R1 is CN, -CH2OH, or-CH2NR3R4; R2 is H, halogen, OH, amino, alkoxy, aralkoxy, aryloxy, cycloalkoxy or acyloxy; R3 is H or 1-3C alkyl; R4 is H, OH, amino, alkoxy, aralkoxy, aryloxy, cycloalkoxy, acyloxy or a heterocyclic gp; n is 1-10;. B is a purine or pyrimidine gp. of formula (II) or (III) Where R5 is H, Cl, Br, OH, amino, mercapto, (di)methylamino, phenylamino, furfurylamino, or hydroxylamino; R6 is H, Cl, Br, OH, amino or mercapto R7 is OH or amino; R9 is H, halogen, Me, CF3, Et or CH2OH). Salts of (I) with acids or bases are also new. (I) can be used as models to explain biological reaction mechanisms in enzyme chemistry, in virus and cancer research and to treat heart and circulatory disorders. (I) can be obtd. from easily available starting materials with almost no side-reactions occurring. Unreacted starting material is easily recovered which compensates/or reduced conversion to (I) because of the 2-phase reaction.

Description

Nueleosidearboxonitriles and their derivatives, and processes for

their preparation The invention relates to new nucleoside carboxylic acid nitriles and their derivatives, of the general formula I. in which R is a hydroxyl group or a hydrogen atom, R1 is -CN, (where R2 is a hydrogen or liäLnatan, a hydroxyl, amino, or acyloxy group Alkoxy, aralkoxy, is), -CH2-N XR3 is), R4 (where Aryloxy, cycloalkoxy for R3 is a hydrogen atom or a methyl, ethyl, propyl or isopropyl group, and R4 is a hydrogen atom, a hydroxyl, amino, alkoxy, aralkoxy, aryloxy, cycloalkoxy or acyloxy group or a radical of a heterocyclic ring), -CHpOH or has, n has a value of 1 to 10 and B is the N-glycosidically bonded radical of a purine or pyrimidine base of the general formula II or III denotes, where R5 is a hydrogen, chlorine or bromine atom, a hydroxyl, amino, mercapto, methylamino, dimethylamino, phenylamino, furfurylamino or hydroxylamino group, R6 is a hydrogen, chlorine or bromine atom, a hydroxyl , Amino or mercapto group, R7 is a hydroxyl or amino group, R8 is an oxygen atom (0), and R9 is a hydrogen, fluorine, chlorine, bromine or iodine atom, a methyl, trifluoromethyl, ethyl or hydroxylmethyl group, and the salts of the compounds of general formula I with acids or bases.

The alkoxy groups can be and have straight-chain or branched 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, with alkoxy groups having 1 to 3 carbon atoms are particularly preferred.

The aryloxy groups contain mono- or polynuclear in the aryl component aromatic rings containing one or more halogen, nitro, Amino, May carry hydroxyl, sulfonic acid or methoxyl substituents.

The cycloaikoxy groups are either monocyclic Substituents with 3 to 6 carbon atoms or around polycyclic substituents with up to 10 carbon atoms. Examples of polycyclic rings are tetralin, decalin and adamantine.

The aralkoxy groups have the general formula -O- (CtI2) x-Ar, where x has a value from 1 to 4, and Ar is one of the aforementioned aryl radicals.

Examples of suitable heterocyclic rings of R4 are pyridine, Quinoline and furan.

Inorganic or organic are used for salt formation with amines Acids, preferably mineral acids, in question. The salt formation takes place by simple Neutralization.

For those compounds of the general formula I in which R1 has the meaning where R2 is a hydroxyl group, the formation of salts by neutralization with inorganic or organic bases is included. The alkali and alkyl ammonium salts are preferred.

In the compounds of general formula I, n has a value of 1 to 10, preferably 1 to 6 and in particular 1 to 4, where n = 1 or 2 whole is particularly preferred.

Nueleosidearboxylic acids were previously only available in individual copies, so especially the short-chain 5'-uronic acids of the nucleosides, which are produced by oxidation arise from nucleosides. Of the compounds of general formula I is only the 5'-deoxy-5 'adenosine acetic acid known (B = adenine, R = OH, R1 = COOH, n = 2); it was obtained, starting from adenosine-5'-aldehyde, via a Wittig reaction (T. E. Walker, H. Eollmann, H.P.C. Hogenkamp in Carbohydr. Res. 27 (1973) 225). from this carboxylic acid were some derivatives are also described.

Under the conventional conditions of a Kolbe nitrile synthesis were Numerous attempts have already been made to produce nucleoside-6'-carboxylic acid nitriles. It is true that nucleoside 5'-tos.ylates are numerous, containing heteroatoms React nucleophiles (kahn et al., Chem. Ber. 98 (1965) 1966, 1705), but succeeded it has not yet been possible to achieve a 5'-C chain extension.

The invention thus also relates to a new process for the preparation of the compounds of the general formula I, which is characterized in that O-tosylated or halogenated nucleosides of the general formula IV are in the 5'-position in which B has the aforementioned meaning, m is 1, R10 is a (protected) hydroxyl group in the case of ribonueleosides and a hydrogen atom in the case of 2'-deoxyribonucleosides, R11 is a (protected) hydroxyl group, and R12 is a halogen atom or a p-toluenesulfonyloxy group (tosyl group) , with a metal cyanide or with o (-AlkaliessigsaUre, in each case in the presence of catalytic amounts of a crown ether, polyalcohol or Tetraalkvlannnoniumsalzes and in the presence of an aprotic solvent to the reaction, then splits off the protective groups by acid hydrolysis, and optionally the resulting compounds of general formula I, in which R1 denotes a nitrile group or a carboxymethyl group, is reacted further in a manner known per se, and, if appropriate, the compounds of the general formula I obtained are converted into the salts in a manner known per se with acids or bases.

The starting compounds (IV) are both 5'-0-tosyl nucleosides which are protected on the sugar as well as sugars halogenated in the 5'-position, preferably the chlorine and bromine derivatives, in question.

In the case of the 2'-deoxyribonucleosides, R10 is a hydrogen atom, and in the ribonucleosides, R10 is a hydroxyl group. The hydroxyl groups R11 and, optionally, R10, are carried out in a manner known per se before the reaction Protective groups protected. For this purpose, e.g. in the case of ribosides, the 2 ', 3'-hydroxyl groups are transferred in 2 ', 3'-isopropylidene, 2', 9'-diacetyl, 2 ', 3'-dibenzylidene or 2', 3'-dianisylidene derivatives. In the case of 2'-deoxyribosides, the D'-hydroxyl group is protected, for example, by a Acetyl, benzyl or tetrahydropyranyl protecting group. These 2 ', 3', 5 'protected or 3 ', 5'-protected ribosides contain the N-glycosidically bound, above defined base radicals B. The preparation of these starting compounds is in the DT-OS 1 795 019, in R. Kuhn, W. Jahn, Chem. Ber. 98 (1965) 1705; R.Dods, J.Roth, J.Org.Chem. 34 (1969) 1627; J. Verheyden, J. Moffatt, J.Org.Chem. 22 (1970) 2319, 2868; ibid. 37, 2289 (1972); K.Kikugawa, M.Ichino, Tetrahedron Bettes 1971, 87 and H.Hogenkamp, Biochemistry 13 (1974) 2736. The starting compounds not described can be prepared in analogy to the known processes.

The starting compounds of the general formula IV are with metal cyanides, preferably alkali and alkaline earth cyanides, or with oC-alkali acetic acid, in the presence catalytic amounts of a crown ether, polyalcohol or tetraalkylammonium salt implemented.

The reaction with metal cyanide leads to 5'-deoxy-5'-cyanonucleosides and in the reaction with d-alkali acetic acid to the 6'-deoxy-6'-nucleoside carboxylic acids, which are also accessible by saponification of the 6'-deoxy-6'-cyanonucleoside.

Crown ethers suitable according to the invention are described in C.P.J.Pedersen, J.Am.Chem.Soc. 89 (1967) 7071, 2495 and 92 (1970) 391. The compounds are preferred 18-crown-6 directly or in substituted form. Of course, they are also similar built crown ethers, e.g. 15-crown-5, can be used. It doesn't matter here whether the crown ethers exist as independent compounds or on an immobile one Carriers are raised.

Instead of crown ethers, polyalcohols with a similar molecular weight can be used or tetraalkylammonium salts can be used.

Aprotic organic solvents are suitable as solvents moderate polarity, preferably absolute dioxane, acetonitrile, tetrahydrofuran, Dioxane, chloroform, methylene chloride or trichlorethylene.

In practicing the method of the invention one goes e.g.

so before that one dissolves nucleoside and crown ether in a little solvent and at room temperature in the presence of a stoichiometric excess (e.g. 2 up to 5 times) on dry alkali metal cyanide for several hours. Response times from The conversion increases only insignificantly over 48 hours and at higher reaction temperatures significant proportions of by-products are obtained in the form of cyclic (anhydro) nucleosides (e.g. N3,5'-adenosine salt; 02,5-cyclouridine).

For work-up, the solid reaction products are separated off.

The supernatant is e.g. column chromatography or by means of preparative Layer chromatography using silica gel or aluminum oxide as the sorbent cleaned. Particular mention should be made of the work-up variant during manufacture of 5'-deoxy-5'-cyanoadenosine. This is where one can rely on the recovery of dispensed with unreacted starting product, which freed from solid reaction products The supernatant was kept at 50 ° C. for 30 minutes, with the starting material largely in cyclic adenosine salt is transferred, which in the subsequent chromatographic Cleansing together with the crown ether and still dissolved salts remains bound to the sorbent.

The protective groups are split off by acid hydrolysis, if appropriate however, the protective groups only become effective after further conversion of the reaction product cleaved.

The reaction of the starting compounds of the general formula IV cyano group introduced with metal cyanide allows a number of chemical reactions on the 5'-deoxy-5'-cyanonucleosides which are optionally protected in the 2 ', 3'-positions of the general formula I (R = H or OH, R1 = CN, n = 1).

With alkali or alkali peroxides, depending on the reaction conditions, nucleoside carboxamides of the general formula I (R = H or OH, R1 = , R2 = -NH2, n = 1) or nucleoside carboxylic acids of the general formula I (R = H or OH, R1 R2 = OH, n = 1).

These nucleoside carboxylic acids can be used in a manner known per se Alcohols are esterified, esters with the alkoxy, aralkoxy, or cycloalkoxy groups are formed.

oil anhydrides can also be reacted by methods known per se, the acyloxy groups mentioned for R2 being introduced. Finally, acid halides (R = H or OH, R1 R2 = halogen, n = 1), which in turn give access to aldehydes (R = H or OH, R1 R2 K, n = 1) open, or can be reacted with hydroxyl groups bonded to aromatic radicals, the aryloxy groups mentioned for R2 being introduced.

The 5'-deoxy-5'-cyanonucleosides and 2 ', 5'-dideoxy-5'-cyanonucleosides can be converted into amines of the general formula I (R = H or OH, R1 R3 = R4 = H, n = 1) can be reduced. The primary amino group thus formed can be alkylated in a manner known per se, where R3 and R4 have the meanings given above.

The reaction of the aforementioned 5'-deoxy-5'-cyanonucleosides and the 2 ', 5'-dideoxycyanoribonucleosides with hydrazoic acid or salts thereof leads to tetrazole derivatives of the general formula I (R = H or OH, R1 = n = 1).

This implementation is described in R.Huisgen, Angew.Chem. 22 (1963) 604 cited.

The esters of the general formula I (R = H or OH, R 1 = R2 = -O-alkyl, n = 1) can be reduced in a manner known per se with complex metal hydrides to the corresponding alcohols (R = H or OI1, R1 = -CH2OH, n = 1), preferably the methyl or Ethyl esters can be used.

When reacting the compounds of the general formula IV with alkali acetic acid under the same conditions as for the reaction with metal cyanides) is obtained directly (after the protective groups have been split off by means of acid hydrolysis) to the compounds chain-extended by two carbon atoms, namely the nucleoside carboxylic acids of the general formula I, in which n has the value 2 (R = H or OH, R1 = -COOH) and to all of the derivatives which can be prepared by the aforementioned reactions.

Starting from the reaction sequence nitrile, carboxylic acid, carboxylic acid ester, Alcohol produced alcohols of the general formula I (R = H or OH, R1 = -CH2OH, n = 1) is obtained after the introduction of the protective groups and after replacing the in 6'-position located hydroxyl group against halogen, preferably chlorine or bromine, or after tosylation of the hydroxyl group in the 61-position to those Compounds of the general formula IV in which m is 2. Through implementation with metal cyanides under the aforementioned conditions one obtains from this (after cleavage of the protecting groups by acid hydrolysis) Cyanonucleosides of the general Formula I, in which n has the value 2 (R = H or OH, R1 = CN) and its cyano group, optionally before splitting off the protective group, all of the aforementioned subsequent reactions is accessible.

By repeating the chain extension (with metal cyanide and / or Alkali acetic acid) can have the side chain substituted in the 4'-position of the sugar can be extended by further CH2 groups.

Of course, it is reduced with each further extension the total yield. On the other hand, the method described is the only one so far Route to the compounds of general formula I (with the exception of 5'-deoxy-5'-adenosine acetic acid) represents, so that you may accept relatively low overall yields. the end however, for commercial reasons, the method of the invention is preferred to those Compounds of general formula I used in which n has a value of not above 4, the compounds with n = 1 and n = 2 being particularly preferred.

The introduction of the cyano group into the nucleosides of the general formula IV provides a convenient way of extending the at the 4 'position of the sugar located second chain and opens up via reactions of classical chemistry Route to the compounds of general formula I.

The advantages of the method described consist on the one hand in the easy accessibility of the output connections, on the other hand in the almost complete Absence of unwanted side reactions. In addition, the simple Recycle and purify unreacted starting material easily, so that a lower one possibly caused by the two-phase reaction Sales can be compensated.

The compounds of general formula I and their salts come similar to the derivatives of 5'-adenosine carboxylic acid (adenosinuronic acid), large Importance to. These compounds serve both as model substances for elucidation biological reaction mechanisms in enzyme chemistry, virus and cancer research, as well as a medicine for cardiovascular and circulatory disorders.

The examples illustrate the invention.

Example 1 5'-Deoxy-5'-cyano-2'.3'-isopropylidene adenosine (A) 920 mg (2 mmol) 5'-0-Tosyl-2 ', 3'-isopropylidene adenosine and 200 mg Kronenather (18-Krone-6) are dissolved in 15 ml of absolute dioxane and then at room temperature with 0.65 g (10 mmol) of dried potassium cyanide stirred vigorously. After 48 hours the fixed Separated components and washed with dioxane. The further work-up takes place according to variant 1 or 2.

Variant 1 After filtration, heated through a short silica gel column the dioxane solution for 30 minutes at 50.degree. Layer chromatographic purification on silica gel (multiple development with toluene / ethanol 10: 1) and elution of the the most intense band with ethyl acetate results in 5'-deoxy-5'-cyano-2 ', 3'-isopropylidene adenosine, which crystallizes in refractive needles from methanol (300 to 350 mg).

Variant 2 By column chromatography on neutral aluminum oxide (Column dimensions 3 × 30 cm) with toluene / methanol 10: 1, starting material is obtained and 5'-deoxy-5'-cyano-2 ', 3'-isopropylidene adenosine in uniform fractions.

Rf values: TLC (silica gel, chloroform / methanol 4: 1) 0.74 TLC (aluminum oxide, Toluene / methanol 10: 1) 0.16 The identity of the 5'-deoxy-5'-cyano-2 ', 3'-isopropylidene adenosine is backed up by mass, PIR, IR and UV spectroscopy.

5 -Desoxv-5 '-cvanoadenosin 250 mg (A) are semi-concentrated in 20 ml Formic acid suspended and left to stand at room temperature. After several days the splitting off of the protective group is complete. The volatile components will be removed at 300C in vacuo. Freeze drying gives pure 5b-deoxy-5'-cyanoadenosine (235 mg).

Rf values: paper chromatography butanol / water (86:14) 0.44 butanol / acetic acid / water (4: 1: 5) 0.80 adenosine-6'-carboxamide and adenosine-6'-calic acid 100 m (A) are suspended in 5 ml of acetone with 3 ml of 30 percent hydrogen peroxide added and made alkaline with a drop of 10 N sodium hydroxide solution. After 30 minutes at 40 ° C. it is neutralized with ethyl acetate and extracted with ethyl acetate. The residue the ethyl acetate phase is taken up with half-concentrated formic acid and 6 days left to stand at room temperature.

After removing the volatile constituents, it is dissolved in dilute Ammonia, relies on an anion exchanger (Dowex 1 x 2, formate form) and elutes first with water, then with formic acid of increasing concentration. From the breakthrough faction pure adenosine-6'-carboxylic acid ureamide is obtained by freeze-drying. In the sour adenosine-6'-carboxylic acid is eluted as a by-product. With prolonged hydrolysis of (A) in sodium peroxide solution, the adenosine-6'-carboxylic acid is formed directly as the main product, which is purified via the anion exchanger (I) owex 1 x 2, FDrmiatform).

The structure of the adenosine-6'-carboxamide and the free acid is secured by mass, PME and UV spectroscopy.

Rf values: paper chromatography butanol / water (86: 14) 0.03 butanol / acetic acid / water (4: 1: 5) 0.29 Example 2 5'-Deoxy-5'-cyano-2'.3'-isopropylideneuridine 440 mg (1 mmol) 5'-O-Tosyl-2 ', 3'-isopropylideneuridine and 100 mg crown ether (18-crown-6) are dissolved in 5 ml of absolute dioxane and stirred with 350 mg of dry potassium cyanide. After 20 hours at room temperature, the solids are separated off and washed with absolute Dioxane. When the dioxane solution is concentrated, cyclo-21,31-isopropylideneuridine precipitates; the suspension is extracted with cold ethyl acetate, which becomes the cyclic nucleoside filtered off. The ethyl acetate solution is obtained by layer chromatography Purification (silica gel, chloroform / methanol 4: 1, elution of the band with Rf = 0.78) pure 5'-deoxy-5'-cyano-2 ', 3'-isopropylideneuridine, which is obtained from methanol in the cold crystallized out.

The splitting off of the protective group with formic acid and the saponification to the amide and uridine-6'-carboxylic acid is carried out analogously to adenosine-5'-carboxylic acid.

Example 3 5'-Deox-5'-cyano-2'.3'-isopropylidenecetidine 440 mg (1 mmol) 5'-0-tosyl-2 ', 3'-isopropylidene cytidine and 130 mg crown ether (18-crown-6) are dissolved in 10 ml of absolute dioxane and stirred at 300C with 125 mg of potassium cyanide. After 48 hours, solid constituents are separated off; one concentrates and extracts with Ethyl acetate. Preparative layer chromatography of the ethyl acetate phase on silica gel with chloroform / methanol 6: 1 gives pure by elution of the most intense band 5'-Deoxy-5'-cyano-2 ', 3'-isopropylidenecetidine (160 mg).

5'-Deoxy-5'-cyanoevtidin '150 mg 5'-Deoxy-5'-cyano-2t, 3'-isopropylidenecetidine are suspended in 2 ml of 50 percent formic acid. After 6 days at room temperature remove the moist components. Freeze drying gives pure 5'-deoxy-5'-cyanocytidine (quantitatively).

6'-cytidinecarboxylic acid 100 mg of 5'-deoxy-5'-cyanocytidine are in 5 ml of 5 percent hydrogen peroxide, pH 10, heated to 40.degree. After 2 hours it sets the weakly alkaline solution on an anion exchanger (Dowex 1 x 2, formate form) and eluted with formic acid 6'-cytidinecarboxylic acid as the main fraction. By freeze drying 70 mg of the desired compound are obtained.

Example 4 uridine-7'-carboxylic acid (= 5'-deoxyuridine-5y-acetic acid) 1.0 g (2.3 mmol) 2 ', 3'-0-isopropylidene-5'-0-tosyluridine and 0.5 g crown ether (18-crown-6) are dissolved in 20 ml of absolute dioxane. It is added with exclusion of moisture with 0.52 g ot sodium sodium acetate (5 mmol) and stir the suspension vigorously, advantageous using an Ultraturrax. After 24 hours at 30 to 40 ° C., the reaction mixture becomes Carefully mixed with water while cooling, weakly acidified with acetic acid and then shaken out 3 times with 50 ml of ethyl acetate each time. The organic phase evaporates it is brought to dryness, taken up in 100 ml of water and brought with dilute ammonia to pH = 7. Insoluble uracil (0.1 g = 0.9 mmol) is separated off. The aqueous solution is evaporated again; the residue is dissolved in 20 ml of 50 percent formic acid suspended and kept at 40 ° C. for 2 days. After removing the acid and absorbing it the product is purified in water (pH 7) through a column of DEAE cellulose Elution with a gradient of 0.05 to 0.5 M triethylammonium bicarbonate. the Fractions with a uridine spectrum (#max = 260 nm) are combined vermax and freeze-dried. 0.21 g is obtained.

Claims

Claims (2)

Claims té1J Nucleosidcarbonsäurenitrile and their derivatives, the general formula I. in which R is a hydroxyl group or a hydrogen atom, R1 is -CN, (where R2 is a hydrogen or halogen atom, a hydroxyl, amino, alkoxy, aralkoxy, aryloxy, cycloalkoxy or acyloxy group), (where R3 is a hydrogen atom or a methyl, ethyl, propyl or isopropyl group, and R4 is a hydrogen atom, a hydroxyl, amino, alkoxy, aralkoxy, aryloxy, cycloalkoxy or acyloxy group or a residue of a heterocyclic ring is), -CHoOH or has, n has a value of 1 to 10 and B is the N-glycosidically bonded radical of a purine or pyrimidine base of the general formula II or III R5 is a hydrogen, chlorine or bromine atom, a hydroxyl, amino, mercapto, methylamino, dimethylamino, phenylamino, furfurylamino or hydroxylamino group, R6 is a hydrogen, chlorine or bromine atom, a hydroxyl, amino or mercapto group, R7 is a hydroxyl or amino group, R8 is an oxygen atom (= o), and R9 is a hydrogen, fluorine, chlorine, bromine or iodine atom, a methyl, trifluoromethyl, ethyl or hydroxylmethyl group, as well as the Salts of the compounds of the general formula I with acids or bases. 2. A process for the preparation of the compounds of the general formula I according to claim 1, characterized in that 0-tosylated or halogenated nucleosides of the general formula IV in the 5'-position in which B has the aforementioned meaning, m is 1, R1o is a (protected) hydroxyl group in the case of ribonucleosides and a hydrogen atom in the case of 2'-deoxyribonucleosides, R11 is a (protected) hydroxyl group, and R12 is a halogen atom or a p-toluslsulfonyloxy group (tosyl group) , with a metal cyanide or with oC-klkaliacetic acid, in each case in the presence of catalytic compounds of a crown ether, polyalcohol or tetraalkylammonium salt and in the presence of an aprotic solvent, then cleaves the protective groups by acid hydrolysis, and optionally the compounds of the general formula I, in the R1 denotes a nitrile group or a carboxymethyl group, reacts further in a manner known per se, and optionally converts the compounds of the general formula I obtained into the salts in a manner known per se using acids or bases.