NO852795L - PROCEDURE FOR THE PREPARATION OF AMINOEBURN ANCARBOXYLIC ACID DERIVATIVES. - Google Patents

Description

The present invention relates to the production of new 9- and 11-aminoeburnane carboxylic acid derivatives. More specifically, the invention relates to the production of new, racemic and optically active 9- and 11-aminoeburnane carboxylic acid derivatives of general formula I

in which

R denotes an amino group; or

denotes a -NH-C0R<1> group in which R<1> denotes a hydrogen atom, an optionally substituted C-]_fg aliphatic, C3_3alicyclic or Cg_^4aromatic hydrocarbyl group or a heteroaromatic group;

or V

denotes a -NH-SO2~R^-group, in which R^ denotes an optionally substituted Cj_^q<a>liphatic, or

Cg_14aromatic hydrocarbyl group;

r<3>denotes a hydrogen atom, an optionally substituted C^_^ q aliphatic group, a C^_g alicyclic or

C6-14 aromatic hydrocarbyl group;

A denotes a hydroxyl group;

B represents a hydrogen atom; or

A and B together form a valence bond; presumed that

R^ is different from methyl group when R denotes an amino group or a -NH-COR^ group in the 11-position, wherein R^ is a methyl group, A denotes a hydroxyl group and B denotes a hydrogen atom;

and

R<3> is different from hydrogen atom when R denotes an amino group and A and B together form a valence bond,

as well as their salts and pharmacological preparations containing these compounds.

According to the invention, a method is provided for the preparation of the new compounds of general formula I and their salts, which method comprises acylation, optionally after hydrolysis, of a racemic or optically active 9- or 11-aminoeburnane carboxylic acid derivative of general formula

II

or a salt thereof, in which R^ denotes a methyl group and, when A and B together form a valence bond, it may also denote a hydrogen atom, after which, if desired, the thus obtained 9-or 11-aminoeburnanecarboxylic acid derivative of general formula I in which R denotes a -NH-COR<1->or NH-SO2R<2-> group in which R<1> and R<2> are as defined above, R^ and R^ are identical, and A and B are as defined for formula I can be esterified or transesterified, and if desired, a racemic or optically active 9- or 11-aminoeburnane carboxylic acid derivative of general formula I wherein R denotes a -NH-COR^- or -NH-SC^R^ group wherein R^ is as above defined, A denotes a hydroxyl group, B denotes a hydrogen atom and R-3 denotes an optionally substituted _^ q aliphatic, C^_g alicyclic or Cg_-]4<a>romatic hydrocarbyl group is hydrolyzed or first esterified or if desired transesterified, and if desired , that the racemic or optically active 9- or 11-aminoeburnanecarboxylic acid derivatives of general formula I in which R denotes an amino group, R-<3>denotes an optionally substituted Cj _^ q aliphatic, £^- 8 alicyclic or cg_-]4aromatic hydrocarbyl group, A denotes a hydroxyl group and B denotes a hydrogen atom, is hydrolysed, after which, if desired, the thus obtained racemic or optically active 9- or

11-aminoeburnanecarboxylic acid derivative of general formula I wherein R denotes an amino group and r<3>, A and B are as defined for general formula I are acylated, after which, if desired, a racemic or optically active 9- or 11-aminoeburnanecarboxylic acid derivative of general formula I wherein R and R 3 are as defined above, A denotes a hydroxyl group and B denotes a hydrogen atom, is dehydrated and, if desired, that the thus obtained racemic or optically active 9- or 11-aminoeburnanecarboxylic acid derivative of general formula I in which R, R^, A and B is as defined for general formula I, is converted to an acid addition salt and/or to a quaternary salt and/or that a thus obtained racemic product dissolves.

In the formulas given above, R1, R2 and R3 can:

as aliphatic hydrocarbyl groups containing 1

to 10 carbon atoms denote straight-chain or branched, saturated or unsaturated groups such as e.g. a methyl-, ethyl-, n-propyl-, isopropyl-, n-butyl-, isobutyl-, sec.-butyl-, tert-butyl-, n-pentyl-, isopentyl-, n-hexyl-, isohexyl-, n-heptyl, isoheptyl, n-octyl, isooctyl, vinyl, acrylic, methacrylic and propenyl groups or the like;

as alicyclic hydrocarbyl groups containing 3

to 8 carbon atoms denote cycloalkyl groups optionally substituted with an alkyl group containing 1 to 4 carbon atoms such as e.g. a cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl or cycloheptyl group etc.;

as aromatic hydrocarbyl groups containing 6

to 14 carbon atoms denote any monocyclic group, e.g. the phenyl group; an isolated polycyclic group, e.g. the diphenylyl group; or a fused polycyclic group, e.g. the naphthyl group.

r<1>as a heteroaromatic group can denote any heteroaryl group consisting of one or more rings each containing 5, 6 or 7 members with one or more identical or different heteroatoms such as nitrogen and/or oxygen and/or sulphur. Such groups are, for example

pyrrolyl, furyl, thienyl, pyridyl, pyranyl, pyrazolyl, imidazolyl, pyrimidinyl, indolyl and quinolyl groups.

Each of the groups r1 , r<2> and R^ can optionally contain one or more of the following substituents: halogen, amino, (C1_g-alkyl)-amino, di-(C1_g-alkyl)-amino, hydroxyl, Cg_- ] ^-aryl, C 1 -g -alkyl, C 1 -g -alkyl, C 1 -g -alkylthio, trifluoromethyl, carboxyl, (C 1 -g -alkyl)-carbonyl, thio, sulfinyl, sulfonyl, nitro, keto, aldehyde (formyl), and cyano and the above-mentioned hetero-aryl groups optionally containing in se the above-mentioned substituents.

The quaternary salts of the compounds of general formula I can e.g. be quaternary alkyl halides containing 1 to 4 carbon atoms in the alkyl part, such as methoiodide, metho-bromide, methochloride, ethoiodide, ethobromide, ethochloride, etc., as well as alkyl sulfates containing 1 to 4 carbon atoms in the alkyl group, such as methosulfate, etc.

The acid addition salts of the compounds of general formula (I) can be formed with inorganic acids such as e.g. the hydrohalides, hydrobromides, sulphates, phosphates and salts of the perhalogenic acids, e.g. perchloric acid, but on the other hand the acid components of these salts can also be organic acids such as e.g. formic acid, acetic acid, propionic acid, glycolic acid, maleic acid, hydroxymaleic acid, fumaric acid, succinic acid, tartaric acid, ascorbic acid, citric acid, malic acid, salicylic acid, lactic acid, cinnamic acid, benzoic acid, phenylacetic acid, p-amino-benzoic acid, p-hydroxybenzoic acid, p- aminosalicylic acid etc. ; alkane sulfonic acids such as e.g. methanesulfonic acid, ethanesulfonic acid and the like; alicyclic sulfonic acids such as cyclohexanesulfonic acid, arenesulfonic acids such as p-toluenesulfonic acid, naphthylsulfonic acid, sulfanilic acid and the like; or amino acids such as aspartic acid, glutamic acid, N-acetylaspartic acid, N-acetylglutaric acid etc.

The compounds of general formula I in which R denotes a 9- or 11-amino group, A and B together denote a valence bond and R 1 denotes a methyl group are known. All the other compounds of formula I are new and exhibit valuable therapeutic properties.

The known compounds of formula I have been described in French patent document 2 342 980 and are prepared by nitration of apovincamine, separation of the resulting mixture of 9- and 11-nitroapovincamine, a separate reduction of these isomers or treatment of the appropriate nitrovincamine with a dehydrating agent and reducing, or treating the appropriate aminovincamine with a dehydrating agent. According to the method according to the invention, on the other hand, both 9- and 11-aminoapovincamine can be produced in a simple way by esterification of the suitable new apovincamic acid. Production of the new aminoapovincamic acids used as starting materials is described in Norwegian patent application 852794. The principle of this process consists in the reduction of the suitable nitroapovincamic acid. 11-acetamidovincamine, the preparation of which has been described in French patent document 2 320 302, is the known compound which is chemically most related to the compounds of general formula I produced by the method according to the invention.

_C 1 -alkyl-1 1 -[(C 1 -C 4 -alkyl)-oxycarbonyl/-aminoapovincamates. (the term "apovincamates" denotes the esters of apovincamic acid which are also called "apovincaminates") which are chemically related, but in principle different from the compounds according to the invention are described in French patent document 2 442 846.

The starting materials of general formula II in which R^ denotes a methyl group can be prepared as described in French patent documents 2 341 585 and 2 342 980.

The starting materials of general formula II in which R^ denotes a hydrogen atom while A and B together denote a valence bond, can be prepared by reduction of the suitable nitro compounds as described in Norwegian patent application 852794.

In the method according to the invention, both the starting materials of general formula II as well as the compounds of general formula I in which R is an amino group can be acylated using any organic carboxylic or sulfonic acid, or a functional derivative thereof, such as halides , anhydrides, etc. containing the appropriate acid residue. For example, acyl chlorides can preferably be used as acyl halides.

Alternatively, the starting materials can be of general formula

II in which r<4> denotes a hydrogen atom while A and B together denote a valence bond is converted in such a way that the acylation is carried out with the reaction mixture to produce the suitable compound of formula II. When e.g. the suitable nitroapovincinamic acid is reduced (as described in Norwegian patent application 852794) and the catalyst or reducing agent is removed after the reduction, the acylating agent can be directly added to the reduced mixture without prior isolation of the suitable aminoapovincinamic acid obtained by the reduction. Thus, it is possible to prepare the acylaminoapovincaminic acid derivatives of general formula I from the suitable nitroapovincaminic acid in a single step, which is of great importance for a synthesis which is considered as a basis for industrial production.

When using a carboxylic or sulfonic acid as acylating agent, the reaction is suitably carried out in an inert organic, polar, aprotic solvent such as dimethylformamide, dimethylsulfoxide, acetonitrile or the like, in the presence of a condensing agent. Connections, e.g. of carbodiimide type such as dicyclohexylcarbodiimide or carbonyldiimidazole can be used for this condensation. This reaction can be carried out at a temperature between 0 and 40°C, preferably at room temperature.

When using an acid anhydride as acylating agent, the reaction can be carried out in an organic solvent such as apolar, aprotic solvents, e.g. optionally halogenated aliphatic or aromatic hydrocarbons, e.g. benzene, dichloromethane, chloroform, etc.; or if desired in a polar protic solvent such as an aliphatic alcohol containing 1 to 6 carbon atoms, e.g. ethanol; or in an excess of the acid anhydride. The temperature of this reaction can be varied within wide limits, e.g. from 0 to 150°C. It is convenient to carry out this reaction at around 20°C.

In acylation using an acyl halide, suitably an acyl chloride, the reaction is carried out in an inert organic solvent, e.g. in aliphatic ethers such as diethyl ether; in cyclic ethers such as tetrahydrofuran; in optionally halogenated aliphatic or aromatic hydrocarbons such as chloroform or benzene; or in organic bases such as pyridine and the like. The reaction is conveniently carried out in the presence of an acid-binding agent such as e.g. inorganic bases such as alkali metal carbonates, e.g. potassium or sodium carbonate; alkali metal hydrides, e.g. sodium hydride etc.; or an organic tertiary base, e.g. triethylamine, pyridine, etc. In some cases, the organic base used can also serve as both a solvent and an acid-binding agent. The reaction temperature can be varied between wide limits, the reaction being suitably carried out at a temperature between 0 and 100°C. When the starting material is an acid, i.e. R^ in general formula II denotes a hydrogen atom, i.e. that the compound to be acylated is acidic in nature, the reaction is carried out by reacting the substance to be acylated with an acylating agent, suitably with an acyl chloride or acid anhydride in an aqueous medium containing a water-miscible organic solvent, e.g. a lower aliphatic alcohol, acetone or the like, and a base. This reaction is carried out at a temperature of between 0 and 100°C, conveniently at room temperature, preferably in the presence of the calculated amount of a base such as inorganic bases such as alkali metal hydroxides, e.g. potassium or sodium hydroxide, or alkali metal carbonates, e.g. potassium or sodium carbonate.

The starting materials of general formula II in which R 1 denotes a hydrogen atom as well as the compounds of general formula I in which R 3 denotes a hydrogen atom can be esterified in a direct or indirect way.

The direct esterification is conveniently carried out by reacting a suitable compound of general formula I or II with an excess of an alcohol of general formula

wherein r<3> is as defined above, except that it is different from a hydrogen atom, preferably in the presence of a catalyst and to the exclusion of any moisture. A strong organic or inorganic acid, e.g. hydrogen chloride, preferably in gaseous form, as well as sulfuric acid or p-toluenesulfonic acid or the like and a water-binding agent, e.g. a suitably selected molecular sieve can be used. The indirect esterification can e.g. is carried out in such a way that a suitable carboxylic acid derivative of general formula I or II is first converted into a salt, possibly in the reaction mixture using: a base, e.g. an alkali metal hydroxide such as lithium, potassium or sodium hydroxide; or an alkali metal carbonate such as sodium or potassium carbonate; or ammonium hydroxide, whereupon the alkali metal or ammonium salt as separated in a suitable manner or as formed and dissolved in the reaction mixture is reacted with a compound of general formula

wherein R-<*> is as defined above except that it is different from a hydrogen atom, and Y denotes an acid residue. When Y in the general formula R^-Y denotes a halogen, e.g. chlorine, bromine or iodine or denotes sulphate, the reaction can conveniently be carried out in an organic aprotic polar solvent such as acetonitrile, dimethylformamide etc. by portionwise addition of a small excess of the suitable halide compound to a suspension of the metal or ammonium salt of the carboxylic acid derivative of general formula I or II in the solvent. This reaction can be carried out at a temperature between 50 and 120°C. When a mixture containing an above-mentioned solvent in water is used, the reaction is carried out in the presence of a suitable phase transfer catalyst, e.g. a suitable tetraalkylammonium halide.

The hydrolysis of the compounds of general formula I in which R is as defined above, A denotes a hydroxyl group, B denotes a hydrogen atom and R-3 denotes an optionally substituted Cj i q aliphatic, g alicyclic, or Cg_^ aromatic hydrocarbyl group, is conveniently carried out in an alkaline medium . Organic solvents containing 5 to 50% water, e.g. aliphatic alcohols such as methanol or ethanol, or aliphatic ketones such as acetone and the like. can be used as solvents. The alkaline conditions are provided by using e.g. an excess of an alkali metal hydroxide such as sodium or potassium hydroxide. The temperature of this reaction can be varied from 20 to 120°C.

The dehydration of the compounds of general formula I in which R and R 3 are as defined above, A denotes a hydroxyl group and B denotes a hydrogen atom, can be carried out by any method usually used for the dehydration of vincaminal alkaloids, suitably splitting off the water in the presence of p-toluenesulfonic acid and its removal by azeotropic distillation. According to a preferred embodiment of this process, a suitable compound of general formula I is boiled in an inert organic solvent, e.g. in an aromatic hydrocarbon such as benzene, toluene, etc. in the presence of p-toluenesulfonic acid, while the water is continuously removed from the system using e.g. a water catchment device.

If desired, the compounds of general formula I produced by the method according to the invention can be converted into quaternary salts. For quaternization, an alkyl halide such as a chloride, bromide, iodide or an alkyl sulfate can advantageously be used in a slight excess in relation to the equivalent amount. This reaction is conveniently carried out in an anhydrous inert organic solvent such as aliphatic alcohols containing 1 to 6 carbon atoms, e.g. absolute methanol, absolute ethanol etc.; or by using ketones, e.g. acetone or butanone, or a nitrile, e.g. acetonitrile as solvent. Quaternization is suitably carried out at a higher temperature.

If desired, the compounds of general formula I prepared by the method according to the invention can be transferred to acid addition salts by using any of the above-mentioned acids.

The acid addition salts may be formed in any inert organic solvent such as in an aliphatic alcohol containing 1 to 6 carbon atoms, by dissolving a racemic or an optically active compound of general formula I in the above solvent, and adding the appropriate acid, or a solution thereof in the above-mentioned solvent to the solution of the compound of general formula I until the solution becomes slightly acidic (ie up to a pH value of 5 to 6). The acid addition salt precipitated from the mixture is then separated in a suitable manner, e.g. by filtering.

Both the racemic and optically active compounds of general formula I as well as the process for producing these compounds fall within the scope of the invention. When a racemic starting material is used, a racemic end product is obtained, while when an optically active starting material is used, the end product is an optically active compound. A racemic end product can be resolved using any known methods of resolution. However, the solution can be achieved at any step of the method according to the invention.

If desired, the racemic and optically active compounds of general formula I as well as their acid addition salts obtained using the method according to the invention can be subjected to a further purification process, e.g. recrystallization. The use of a solvent for the recrystallization depends on the solubility and crystallization characteristics of the solvent in question.

The racemic and optically active compounds of general formula I as well as their pharmaceutically acceptable acid addition and quaternary salts exhibit valuable therapeutic properties, namely vasodilatory, spasmolytic, antihypoxic and anticonvulsant effects.

The vasodilatory effect was studied in dogs anesthetized with a chloralose-pentobarbital mixture. The extremity blood flow was measured in the femoral artery, while the cerebral blood flow was observed in the internal carotid artery. Electromagnetic flow meters were used to measure the blood flow. The test compounds were administered intravenously at a dose of 1 mg/kg body weight to 6 dogs, and the percentage changes in the measured parameters were assessed. Ethyl (+)-apovincamate, a commonly used therapeutic cerebral vasodilator was used as a reference compound.

Circulatory effect (% change) on intravenous doses of 1 mg/kg body weight in anesthetized dogs

The spasmolytic activity of the compounds was determined using the traditional method, ie on isolated guinea pig ileum (Magnus, R., Pflugers Arch. 102, 123 (1904)). Papaverine and ethyl (+)-apovincamate used as therapeutic spasmolytic agents were used as reference compounds.

Inhibition of barium chloride-induced contraction of guinea pig ileum

According to one method, the antihypoxic activity was studied in conscious mice under normobaric hypoxia. Five male mice were placed in a glass cylinder with a volume of 3 litres, through which a gas mixture consisting of 96% nitrogen and 4% oxygen flowed. The time interval from this time up to the point of death for the animals was measured for 15 minutes as a maximum. The animals were considered protected when they were alive twice as long as the time until death of the untreated animals. The test compounds were administered intraperitoneally to 10 animals each at a dose of 50 mg/kg body weight 30 minutes before placement in the glass cylinder.

Antihypoxic effect of intraperitoneal doses of 50 mg/kg body weight in conscious mice under normobaric hypoxia

The antihypoxic activity was also investigated using two other methods.

According to the asphyxic anoxia test (Caillard 0. et al.: Life Sci. 16, 1607 (1975)) the animals were fasted for 16 hours and then treated orally, and one hour after the treatment they were placed in tightly closed glass flasks with a volume of 100 ml. The survival time was considered as the time interval from closing the flask up to the last respiration. The animals were considered protected when they were alive for a period of time 30% longer than the mean survival time of the control group.

According to the hypobaric hypoxia test (Baumel J. et al.: Proe. Soc. Biol. N.Y. 132, 629 (1969)), animals were fasted for 16 hours and then treated orally, and one hour after treatment they were placed in a desiccator in which the pressure was reduced to 170 mm/Hg within 20 seconds. The survival time was recorded from this time up to the last respiration. The animals were considered protected when they were alive for a period of time 100% longer than the mean survival time of the control group. The ED5Q value (ie the dose that was 50% effective) was calculated from the percentage of protected animals using the probit analysis method.

The anticonvulsant activity was studied using the following methods.

Using the maximal electroshock test (Swinyard E.A. et al.: J. Pharmacol. Exp. Ther. 106, 319 (1959)), a shock (20 mA, 0.2 sec, HSE Shock Device Type 207) was administered to mice weighing 22 to 24 g using corneal electrodes. Animals were considered protected when the tonic extension of their lower extremities was abolished due to the effect of the treatment.

Using the Metrazole Impact Method (Everett, G.M. and Richards, R.K.: J. Pharmacol. Exp. Ther., 81, 402

(1944)) a subcutaneous dose of 125 mg/kg pentylenetetrazole was administered to mice after pretreatment. The persistent clonic convulsions as well as the tonic extensor convulsions abolished by the treatment were recorded.

Using the ironing layer method (Kerley, T.L. et al.: J. Pharmacol. Exp. Ther., 132, 360 (1961)), tonic extensor convulsions were induced by an intraperitoneal dose of 2.5 mg/kg strychnine nitrate. Animals were considered protected if tonic extensor convulsions were abolished as an effect of the treatment, whereby the animals remained alive.

The neurotoxic side effects were observed using the following methods.

Using the muscle incoordination model (rotating rod method) (H. Kwibara et al.: Japan J. Pharmacol. 27, 117 (1977)), those animals were selected - after previous training, which could remain for 120 seconds on a horizontal rod with a diameter of 20 mm which rotated at 12 revolutions per minute. A muscle incoordination effect was observed when the animals fell from the rotating rod during this time limit.

When determining the muscle relaxant activity (stretch test), male mice weighing 18 to 22 g were stretched by the front legs on a horizontal wire with a diameter of 5 mm. The animals were considered to exhibit hypomyotonia if they did not pull up the hind legs to the fore legs as an effect of the treatment within 5 seconds.

On the basis of the investigations described above, it can be determined that the biological activity is very advantageously influenced by a substitution in the "A" ring. This is shown above all in a selective increase in blood flow. The cerebral blood flow is specifically increased and the extremity blood circulation is not or very little influenced by some of the compounds of general formula I, while other compounds within the framework of general formula I intensify the extremity circulation without a cerebral activity. In general, the compounds substituted in the 11-position, especially with a benzoylamino group, have a stronger cerebral vasodilating effect than the reference compounds with a similar chemical structure, while the compounds substituted with the same group in the 9-position mainly exhibit an extremity vasodilating effect.

In addition to the circulatory effects, the compounds also exhibit a direct spasmolytic effect on non-striated muscles which is identical or higher than the effect of papeverine used as a reference compound.

The compounds of general formula I exhibit excellent anticonvulsant activity; they are more effective than rnephenytoin used as a reference compound, while neurotoxic side effects are not observed even after administration of a 10-fold amount of the anticonvulsant effective dose, while neurotoxic side effects appear after administration of a 3- to 6-fold amount of the anticonvulsant effective dose of the reference compound. Thus, the therapeutic ratio (safety index) for the reference compound is much narrower.

The anticonvulsant and antihypoxic effect of the compounds produced according to the invention together with their activity in terms of increasing the cerebral blood flow indicate a particularly advantageous therapeutic applicability in diseases in which the cerebral oxygen supply is short-term or chronically disturbed.

The compounds of general formula I can be transferred to pharmaceutical preparations by mixing these with common non-toxic, inert solid or liquid carriers and/or excipients which are usually used in such preparations and which are applicable for parenteral or enteral administration. For example, water, gelatin, lactose, starch, pectin, magnesium stearate, stearic acid, talc and vegetable oils such as peanut oil or olive oil etc. can be used as carriers. The active ingredients can be formulated into common pharmaceutical preparations, e.g. for solid forms (such as round or angled tablets, dragees, capsules, e.g. hard gelatin capsules, pills, suppositories etc.) or for liquid forms

(such as oily or aqueous solutions, suspensions, emulsions, syrups, soft gelatin capsules, injectable oily or aqueous solutions or suspensions, etc.). The quantity of the solid carrier materials can be varied within wide limits, these are preferably used in an amount of between 25 mg and 1 g. The preparations can optionally contain the commonly used pharmaceutical additives, e.g. preservatives, stabilizers, wetting agents and emulsifiers, as well as salts which are useful for adjusting osmotic pressure, buffers, aromatizing and flavoring agents, etc. Furthermore, the preparations may possibly contain other known, therapeutically valuable compounds. The preparations are preferably formulated in unit dosage forms suitable for the desired method of administration.

The pharmaceutical preparations are produced using common methods including, for example, sieving, mixing, granulating and pressing or dissolving the compounds in order to formulate (transfer) these into the suitable preparations. The preparations can be subjected to further operations (e.g. sterilization) which are usually used in the pharmaceutical industry.

The invention is further illustrated in the following examples.

EXAMPLE 1

Preparation of 11-benzoylaminoapovicamic acid

3.37 g (0.01 mol) of (+)-11-aminoapovincinamic acid was dissolved in 100 ml of 1N aqueous sodium hydroxide solution, and 1.7 ml (0.015 mol) of benzoyl chloride was added dropwise to the solution at room temperature and with stirring. The mixture was stirred for two hours after which the same amount of benzoyl chloride was added and the mixture was stirred for another two hours. The pH value of the mixture was adjusted to a neutral value by the addition of 10% aqueous hydrochloric acid, the precipitated crystals were filtered, washed with 50 ml of water and were heated to 50 to 60°C, and then 50 ml of cold water, and were dried under formation of 3.30 g (75% yield) of the desired compound, m.p.: 244-248°C.

Analysis

Calculated for C27H27N3O3 (molecular weight 441.52):

C 73.45, H 6.16, N 9.52%

found: C 73.62, H 6.82, N 9.48%.

<1>H-NMR spectrum (DMSO-d6, 6 ): Et: 0.94t(3), H-3: 4.10s(1),

H-1 5: 6.00s(1 ) , NH: 7.95s(1 ) , Ar-H: 7.3-7.6m(6), Hortho: 7.09-8.05m(2), COOH : 10.10s(1 ) , skeletal protons: 1.10-3.4m.

EXAMPLE 2

Preparation of 11-(2-thiophenecarbonylamino)-apovincamic acid

3 ml (0.03 mol) of thiophene-2-carbonyl chloride was added dropwise to a solution of 3.37 g (0.01 mol) of (+)-11-aminoapovincinamic acid in 100 ml of 1N aqueous sodium hydroxide solution at room temperature and under stirring. After stirring for half an hour, the pH value of the mixture was adjusted to a neutral value by the addition of 10% aqueous hydrochloric acid. The precipitated crystals were filtered, washed three times, each time with 40 ml of water and were dried to give 3.26 g (73% yield) of the desired compound, m.p.: 246-248°C.

Analysis

Calculated for C25H25<N>3O3S (molecular weight 447.5):

C 67.10, H 5.63, N 9.39%,

found: C 67.35, H 6.00, N 9.40%.

EXAMPLE 3

Preparation of ethyl 11-aminoapovincamate

Method a)

A mixture containing 3.95 g (0.01 mol) of ethyl 1 1-nitroapovincamate in 50 ml of ethanol, 10 ml of concentrated hydrochloric acid and 6 g of tin powder was stirred at 100°C for one hour and then filtered hot. The solution thus obtained was evaporated to dryness under reduced pressure, the residue was taken up in 100 ml of water and made alkaline to pH 10 by the addition of 1N aqueous sodium hydroxide solution. The precipitate was filtered, washed three times, each time with 40 ml of 1% aqueous sodium hydroxide solution, and then three times, each time with 40 ml of water, and was dried to give 2.80 g (77% yield) of the desired compound, m.p.: 86-88°C.

<1>H-NMR spectrum (CDC13,6 ): Et: 1.00t(3), 1.90q(2), EtO: 1.40t(3) , 4.40q(2) , NH2: 3.23 (2) , H-3: 4.1 0s(1 ) ,

H-15: 6.07s(1), skeletal protons: 1.5-3.2m.

Method b)

A mixture containing 3.83 g (0.01 mol) of ethyl 11-aminovincamate and 7.0 g of p-toluenesulfonic acid in 150 ml of benzene was refluxed using a water trap for eight hours. The mixture was then cooled to room temperature, 100 ml of water was added and the mixture made alkaline to pH 8 by addition of concentrated aqueous ammonium hydroxide solution. The aqueous phase was separated, the benzene layer was extracted three times, each time with 100 ml of water, was dried over anhydrous sodium sulfate, filtered, whereupon the filtrate was evaporated to dryness under reduced pressure. The residue was triturated with ether, the crystals obtained were filtered, washed with ether and dried to give 3.0 g (82% yield) of the desired compound.

EXAMPLE 4

Preparation of ethyl 11-methanesulfonylaminoapovincamate mono-hydrochloride

A solution of 0.6 ml (0.008 mol) of methanesulfonyl chloride in 10 ml of chloroform was added to a solution of 1.62 g (0.0044 mol) of ethyl 11-aminoapovincamate in 10 ml of anhydrous pyridine while cooling in an ice bath, after which the mixture was stirred at 0°C for three hours and then evaporated to dryness under reduced pressure. The residue was taken up in a mixture of 50 ml of ethyl acetate, 25 ml of saturated aqueous sodium bicarbonate solution and 50 ml of water. The two layers were separated, the ethyl acetate phase was washed twice, each time with 30 ml of water, was dried and evaporated to dryness under reduced pressure. The residue which is the base form of the desired compound (1.86 g, 96% yield) was dissolved in 15 ml of acetone and acidified to pH 3 by addition of ethanolic hydrogen chloride solution. The crystals obtained after the addition of 45 ml of diisopropyl ether were filtered, washed with ether and dried to give 1.56 g (74% yield) of the monohydrochloride form of the desired compound, m.p.: 230-234°C.

Analysis

Calculated for C23H29N304S-HC1 (molecular weight 480.11):

C 57.53, H 6.29, N 8.75, S 6.67, Cl 7.38%, found: C 57.42, H 6.87, N 8.56, S 6.43, Cl 7 ,40%.

EXAMPLE 5

Preparation of ethyl-11-aminovincamate

A mixture containing 7.4 g (0.02 mol) of 11-aminovincamine and 0.5 g of potassium tert-butoxide in 500 ml of ethanol was refluxed for two hours and then evaporated to dryness under reduced pressure. The residue was taken up in a mixture of 200 ml of water and 40 ml of ethanol, the crystals obtained were filtered, washed with a mixture containing 100 ml of water and 20 ml of ethanol in three portions, and were dried to give 5.43 g (71 % yield) of the desired compound, m.p.: 184-186°C.

1-NMR spectrum (CDCl3, 6 ): Et: 0.85t(3), CH2: overlap,

H2-15: 2.08d(1), 2.16d(1) (Jgem= 14 Hz), NH2: 3.80, CH2-0: 4.25q(2), H-3: 3.84s(1 ), H-9: 7.30d(1), H-10: 6.60dd(1), H-12: 6.41d(1).

EXAMPLE 6

Preparation of ethyl-9-aminoapovincamate monohydrochloride Method a)

From 3.83 g (0.01 mol) of ethyl-9-aminovincamate and using the method described in Example 3, 2.84 g (78% yield) of the desired product was obtained as the base form, which was dissolved in 20 ml of acetone and was acidified to pH 3 by adding an ethanolic solution of hydrogen chloride. The crystals obtained after addition of 20 ml of diisopropyl ether were filtered, washed with ether and dried to give 2.7 g (69% yield) of the monohydrochloride form of the desired compound, m.p. 218-222°C.

Analysis

Calculated for C22H27N3O3•HCl (molecular weight 401.96):

C 65.68, H 6.71, N 10.44, Cl 8.83%,

found: C 65.86, H 6.90, N 10.28, Cl 8.78%.

Method b)

A solution containing 3.37 g (0.01 mol) (-)-9-aminoapovincinamic acid in 100 ml of anhydrous ethanol was saturated with dry gaseous hydrogen chloride in the presence of 1 g of a molecular sieve (3 Å, Aldrich 20, 859-2) , whereupon the mixture was refluxed under a continuous supply of hydrogen chloride for three hours. The mixture was evaporated to dryness and 20 ml of ethyl acetate was added to the residue. The crystals obtained were filtered, washed with ethyl acetate and dried to give 3.13 g (86% yield) of the desired compound, m.p.: 218-222<0>C.

EXAMPLE 7

Preparation of ethyl 1-9-methanesulfonylaminoapovincamate mono-hydrochloride

0.37 ml (0.005 mol) of methanesulfonyl chloride was added to a solution containing 1.10 g (0.0027 mol) of ethyl 9-amino-apovincamate monohydrochloride in 15 ml of anhydrous pyridine. The mixture was stirred at 0°C to 5°C for two hours, and then evaporated to dryness under reduced pressure, the residue was dissolved in 50 ml of chloroform and the organic solution was extracted with 25 ml of a saturated aqueous sodium carbonate solution and then three times , each time with 30 ml of water. The chloroform layer was dried over anhydrous sodium sulfate, filtered and the filtrate was evaporated to dryness to give the oily base form of the desired compound in a yield of 1.09 g (91%). This base was dissolved in 40 ml of acetone, and the solution was acidified to pH 4 by adding an ethanolic hydrogen chloride solution. The crystals obtained after addition of ether were filtered, washed with ether and dried to give 1.13 g (96% yield) of the monohydrochloride form of the desired product, m.p.: 189-192°C.

Analysis

Calculated for C23H29<N>304S«HC1 (molecular weight 480.11):

C 57.53, H 6.29, N 8.75, S 6.67, Cl 7.38%, found: C 57.70, H 6.80, N 8.72, S 6.40, Cl 7 .51%.

EXAMPLE 8

Preparation of ethyl-9-aminovincamate

From 7.4 g (0.02 mol) of 9-aminovincamine and using the method described in example 5, 5.82 g (76% yield) of the desired product was obtained, m.p.: 232-234< 0>C.

EXAMPLE 9

Preparation of methyl-11-(4-nitrobenzoylamino)-apovincamate

1.3 g (0.007 mol) of 4-nitrobenzoyl chloride was added to a solution containing 1.3 g (0.0037 mol) of 11-aminoapovincamine in 10 ml of anhydrous pyridine, after which the mixture was stirred at room temperature for one hour. A mixture containing 100 ml of ice water and 150 ml of ethyl acetate was added to the solution, and the mixture was made alkaline to pH 8 by the addition of 1N aqueous sodium hydroxide solution. The ethyl acetate layer was separated, washed four times, each time with 25 ml of water, was dried over anhydrous sodium sulfate, filtered, whereupon the filtrate was evaporated to dryness under reduced pressure. The residue was thoroughly triturated with 100 ml of ether, the crystals obtained were filtered, washed with ether and dried to give 1.68 g (91% yield) of the desired compound, m.p.: 206-208°C

<1>H-NMR spectrum (CDC13, 6 ): Et: 1.02t(3), CH3O: 3.98s(3),

H-3: 4.02s(1), H-15: 6.28s(1), NH: 8.58s(1), ArH: 7.32-8.08m(7), skeletal protons: 1,4- 3.26.

EXAMPLE 10

Preparation of methyl 11-(2-bromobenzoylamino)-apovincamate mono-hydrochloride

3.51 g (0.01 mol) of 11-aminoapovincamine and 2 ml of triethylamine were dissolved in 40 ml of anhydrous benzene. After adding a solution containing 5.12 g (0.023 mol) of 2-bromobenzoyl chloride in 10 ml of benzene to the above mixture at room temperature with stirring, the solution was stirred at room temperature for four hours and was then evaporated to dryness. under reduced pressure. The residue was dissolved in 100 ml of water and 50 ml of ethyl acetate, and was made alkaline to pH 8 by adding

deposition of concentrated aqueous ammonium hydroxide solution. The ethyl acetate layer was separated, the aqueous phase was extracted twice, each time with 5 mL of ethyl acetate, and the combined ethyl acetate solution was washed three times, each time with 50 mL of water, was dried over anhydrous sodium sulfate, filtered, and the filtrate was evaporated to dryness under forming 4.16 g (78% yield) of the base form of the desired compound as an amorphous residue.

<1>H-NMR spectrum (CDC13, 6): Et: 1.01t(3), 1.90q(2), H-3: 4.1 4s( 1 ), CH3O: 4.00s(3), H-15: 6.19s(1) ArH+NH: 7.05-7.90m(8), skeletal protons: 0.8-3.4m(10) The base obtained above was dissolved in 50 ml of acetone and was acidified to pH 3 by adding an ethanolic hydrogen chloride solution. The crystals obtained after addition of ether were filtered, washed with ether and dried to give 3.93 (69% yield) of the monohydrochloride form of the desired compound, m.p.: 208-212°C.

EXAMPLE 11

Preparation of 11-(2-fluorobenzoylamino)-vincamine

2.1 g (0.015 mol) of 2-fluorobenzoic acid was dissolved in 100 ml of anhydrous dimethylformamide, and to this solution 4.0 g (0.02 mol) of dicyclohexylcarbodiimide was first added, and after stirring for ten minutes, 3.7 g (0.01 mol) of 11-aminovincamine at 0°C with stirring. The mixture was further stirred at 0°C for one hour, and then allowed to stand at room temperature overnight. The precipitated dicyclohexylurea was filtered, and the filtrate was evaporated to dryness under reduced pressure. The residue was dissolved in 400 ml of ethyl acetate and allowed to stand in a refrigerator overnight. The dicyclohexylurea that crystallized out was repeatedly filtered, and the filtrate was extracted four times, each time with 50 ml of 1N aqueous hydrochloric acid, and then twice, each time with 50 ml of water, and finally three times, each time with 50 ml of saturated aqueous sodium bicarbonate solution and twice, each time with 50 ml of water. The ethyl acetate layer was dried over anhydrous sodium sulfate, filtered and the filtrate was evaporated to dryness. The residue was dissolved in a warm

mixture containing 50 ml of ethyl acetate and 250 ml of petroleum ether. After cooling, crystals were obtained which were filtered, washed with petroleum ether and dried to give 3.8 g (78% yield) of the desired product, m.p.: 202-205°C.

<1>H-NMR spectrum (CDC13,6): Et: 0.90t(3), CH3O: 3.90s(3), OH:

4.76s(1 ) , Ar-H: 7.05-8.70m(7), skeletal protons: 1 .00-3.4m(12).

EXAMPLE 12

Preparation of 11-(3,4,5-trimethoxybenzoylamino)-vincamine

2.3 g (0.01 mol) of 3,4,5-trimethoxybenzoyl chloride was added to a solution containing 1.85 g (0.005 mol) of 11-aminovincamine in 75 ml of anhydrous pyridine at room temperature and with stirring. The solution was stirred at room temperature for two hours and then evaporated to dryness under reduced pressure. The residue was dissolved in 50 ml of ethyl acetate and 50 ml of water, and was made alkaline to pH 8 by the addition of concentrated aqueous ammonium hydroxide solution. The layers were separated, the ethyl acetate phase was washed three times, each time with 25 ml of water, was dried and evaporated to dryness. The residue was dissolved in 25 ml of hot methanol, and after adding 100 ml of diisopropyl ether, the solution was allowed to stand in a refrigerator overnight. The crystals obtained were filtered, washed with diisopropyl ether and dried to give 2.13 g (76% yield) of the desired compound, m.p.: 154-158°C.

EXAMPLE 13

Preparation of 11-pivaloylaminovincamine

0.5 ml (0.004 mol) of pivaloyl chloride was added to a solution containing 0.74 g (0.002 mol) of 11-aminovincamine in 30 ml of anhydrous pyridine at 0°C and with stirring. The mixture was further stirred at the same temperature for two hours after which

20 ml of water was added and the solution was made alkaline to pH 8 by the addition of concentrated aqueous ammonium hydroxide solution. The precipitated crystals were filtered, washed with water and dried to give 0.71 g of the desired product (78% yield), mp: 140-144°C. <1>H-NMR spectrum (CDCl3,S ): Et: 0.88t(3), CH3: 1.30s(9), CH3O: 3.87s(1 ) , H-3: 3 , 90s (1 ) , OH: 4.20s(1 ), Ar-H+NH: 6.97-7.65m(4), skeletal protons: 1.45-3.5m.

EXAMPLE 14

Preparation of 9-benzoylaminovincamine

A solution containing 3.5 ml (0.03 mol) of benzoyl chloride in 20 ml of benzene was added portionwise to a suspension of 5.52 g (0.015 mol) of 9-aminovincamine in 150 ml of anhydrous benzene and 5 ml of anhydrous pyridine with stirring. After stirring the mixture for a further three hours at room temperature, 60 ml of water was added and the pH was adjusted to 8 by the addition of concentrated ammonium hydroxide solution. The benzene phase was separated, washed five times, each time with 20 ml of water, was dried over anhydrous sodium sulfate, filtered and the filtrate was evaporated to dryness under reduced pressure. The residue was thoroughly triturated with 50 ml of diisopropyl ether, the crystals obtained were filtered and washed with ether to give 4.92 g (69% yield) of the desired compound, mp: 152-156°C.

<1>H-NMR spectrum (CDCl3, 6 ): Et: 0.90t(3), 1.65q(2), CH30: 3.85s(3), H-3: 3.88s(1), OH : 4.75s(1), NH: 8.46s(1), Ar-H: 6.8-8.0m(8).

EXAMPLE 1 5

Preparation of 9-acetoamidovincamine

To a solution of 6.6 g (0.018 mol) of 9-aminovincamine in 600 ml of methanol, 66 ml of acetic anhydride was added dropwise at 0°C, after which the solution was further stirred at 0°C for 30 minutes. 800 g of ice water and 120 g of potassium carbonate were then added to the mixture with stirring. The methanol was distilled off under reduced pressure and the remaining aqueous mixture was extracted five times, each time with 100 ml of dichloromethane. The combined dichloromethane solution was washed three times, each time with 100 mL of water, dried over anhydrous sodium sulfate, filtered, and the filtrate was evaporated to dryness. After adding 50 ml of ether to the residue, the precipitated crystals were filtered, washed with ether and dried. 5.92 g (80% yield) of the desired compound were thus obtained, m.p.: 144-1470c.

EXAMPLE 16

Preparation of 11-(2-thiophenecarbonyl)-aminovincamine

A solution of 7.2 ml (0.067 mol) of thiophene-2-carbonyl chloride in 20 ml of benzene was added dropwise to a mixture containing 19.9 g (0.054 mol) of 1 1-aminovincamine in 100 ml of pyridine at 20°C. while stirring. The mixture was stirred at the same temperature for a further two hours, after which 50 ml of a saturated aqueous sodium bicarbonate solution, 50 ml of water and 200 ml of ethyl acetate were added. After performing the extraction, the phases were separated, the ethyl acetate layer was washed twice, each time with 30 ml of water, was dried over anhydrous sodium sulfate, filtered, whereupon the filtrate was evaporated to dryness under reduced pressure. After adding 200 ml of ether to the residue, the crystals obtained were filtered, washed four times, each time with 50 ml of ether and dried. 18.4 g (71% yield) of the desired product were thus obtained, m.p.: 229-231°C.

EXAMPLE 17

Preparation of 11-(2-thiophenacetyl)-aminovincamine

To a solution of 0.3 g (0.0022 mol) thiophene-2-acetic acid in 10 ml of anhydrous dimethylformamide was added 0.45 g of dicyclohexylcarbodiimide. The solution was stirred at room temperature for 15 minutes, after which 0.74 g (0.002 mol) of 11-aminovincamine was added. The mixture was stirred at room temperature for 24 hours and then allowed to stand in a refrigerator overnight. The precipitated dicyclohexylurea was filtered off and the filtrate was evaporated to dryness under reduced pressure. The residue was dissolved in 30 ml of ethyl acetate and was extracted successively with 10 ml of saturated aqueous sodium bicarbonate solution and then three times, each time with 10 ml of water. The ethyl acetate phase was dried over anhydrous sodium sulfate, filtered and the filtrate was evaporated to dryness under reduced pressure. After adding 20 ml of ether to the residue, the precipitated crystals were filtered and washed with ether. After drying, 0.51 g (52% yield) of the desired compound was obtained, m.p.: 153-155°C.

<1>H-NMR spectrum (CDCl3, 6): Et: 0.90t(3), 1.7q(2), CH3O: 3.88s(3), CH2CO: 3.94s(2), H-3 : 4.00s(1), OH: 4.70(1), Ar-H: 6.80-7.65m(6), CONH: 7.48(1).

EXAMPLE 18

Preparation of 9-acetamidoapovincamine

A mixture containing 5.6 g (0.014 mol) of 9-acetamidovincamine and 6.8 g of p-toluenesulfonic acid in 300 ml of benzene was refluxed using a water trap for four hours. The mixture was then cooled, 200 ml of water was added, the solution was made alkaline to pH 8 by the addition of concentrated aqueous ammonium hydroxide solution and was extracted. The benzene layer was washed four times, each time with 100 ml of water, was dried over anhydrous sodium sulfate and filtered. After evaporation of the filtrate to dryness under reduced pressure, the residue obtained was dissolved in 50 ml of hot ethyl acetate, and after cooling, the precipitated crystals were filtered and washed with ethyl acetate to give 5.0 g (91% yield) of the desired product, sm .p.: 138-140°C.

<1>H-NMR spectrum (CDCl3, 6 ): Et: 0.99t(3), CH3CO: 2.66s(3),

CH3O: 3.80s(3), H-3: 4.05s(1), H-15: 6.18s(1), Ar-H: 7.0-7.65m(3).

EXAMPLE 19

Preparation of 11-(3,4,5-trimethoxybenzoylamino)-apovincamine

A mixture containing 1.3 g (0.0023 mol) of 11-(3,4,5-trimethoxybenzoylamino)-vincamine and 1.0 g of p-toluenesulfonic acid in 50 ml of benzene was refluxed using a water trap for two hours . After cooling, 20 ml of water was added to the mixture, and the whole was made alkaline to pH 8 by the addition of concentrated aqueous ammonium hydroxide solution. After extraction, the benzene phase was washed three times, each time with 20 ml of water, was dried over anhydrous sodium sulfate and filtered. After evaporation of the filtrate to dryness under reduced pressure, the evaporation residue was dissolved in 3 ml of hot acetone, 15 ml of petroleum ether was added, and after cooling the precipitated crystals were filtered off and washed with ether. After drying, 1.03 g (83% yield) of the desired product was obtained, m.p.: 150-152°C.

<1>H-NMR spectrum (CDC13, 6 ): Et: 1.00t(3), CH3CO: 3.98s(3),

CH 3 O: 3.90s(9); H-3: 4.01s(1); H-15: 6.28s(1), Ar-H: 7.1-7.8m(5), NHCO: 8.30s(1).

EXAMPLE 20

Preparation of 11-pivaloylaminoapovincamine

A mixture containing 0.66 g (0.0015 mol) of 11-pivaloylaminovincamine and 0.70 g of anhydrous p-toluenesulfonic acid in 20 ml of benzene was refluxed using a water trap for three hours, then cooled, after which

20 ml of water was added. The mixture was made alkaline to pH 8 by the addition of concentrated aqueous ammonium hydroxide solution and was extracted. The benzene phase was washed four times, each time with 10 ml of water, was dried over anhydrous sodium sulfate and filtered. After evaporation of the filtrate to dryness under reduced pressure, the residue was dissolved in 20 ml of hot hexane containing a few drops of acetone. After cooling, the crystals obtained were filtered, washed with hexane and dried to give 0.44 g (68% yield) of the desired product, m.p.: 110-114<0>c. <1>H-NMR spectrum (CDCl3, 6 ): Et: 0.97t(3), 1.92q(2), CH3: 1.35s(9), CH3O: 3.93s(1), H-3 : 4.07s(1), Ar-H+NH: 7.0-7.68m(4).

EXAMPLE 21

Preparation of 11-acetamidoapovincamine

A mixture containing 18.1 g (0.044 mol) of 11-acetamidovincamine and 22 g of p-toluenesulfonic acid in 900 ml of benzene was refluxed using a water trap for five hours, then cooled, after which 400 ml of water was added. The mixture was made alkaline to pH 8 by the addition of a concentrated aqueous ammonium hydroxide solution. After extraction, the benzene layer was washed three times, each time with 300 ml of water, was dried over anhydrous sodium sulfate, filtered, whereupon the filtrate was evaporated to dryness under reduced pressure. After washing the residue with 50 ml of diisopropyl ether and drying, 14.35 g (83% yield) of the desired product were obtained, mp: 136-140°C.

<1>H-NMR spectrum (CDC13,6 ): Et: 0.98t(3), 1.83q(2), CH3CO: 2.08s(3), CH3O: 3.90s(3), H-3 : 4.05s(1), H-15: 6.06s(1), Ar-H+NH: 6.97-7.58m(4).

EXAMPLE 22

Preparation of ethyl-9-benzoylaminovincamate

A solution containing 1.89 g (0.004 mol) of 9-benzoylaminovincamine and 0.1 g of potassium tert-butoxide in 30 ml of anhydrous ethanol was refluxed for one hour and then evaporated to dryness. The residue was dissolved in 50 ml of ethyl acetate. and was extracted three times, each time with 15 ml of water. The ethyl acetate phase was dried over anhydrous sodium sulfate, was filtered and the filtrate was evaporated to dryness under reduced pressure. After trituration of the residue with ether, the crystals obtained were filtered, washed with ether and dried to give 1.32 g (68% yield) of the desired compound, /ot/D= +44.82° (c = 1 , dichloromethane ).

EXAMPLE 23

Preparation of ethyl 9-benzoylaminoapovincamate

A mixture containing 1.22 g (0.0025 mol) of ethyl 9-benzoylaminovincamate and 1.3 g of p-toluenesulfonic acid in 50 ml of benzene was refluxed using a water trap for two hours and then cooled. After adding 50 ml of water, the pH was adjusted to 8 using a concentrated aqueous ammonium hydroxide solution. After extraction and separation, the benzene layer was washed four times, each time with 20 ml of water, was dried over anhydrous sodium sulfate, filtered, whereupon the filtrate was evaporated to dryness under reduced pressure. After trituration of the residue with 10 ml of hexane, the crystals obtained were filtered, washed with hexane and dried to give 0.93 g (79% yield) of the desired product, m.p.: 112-116°C. /ct/D = +1 86.96° (c = 1 , dichloromethane).

<1>H-NMR spectrum (CDCl3, 6): Et: 1.00t(3), 1.90q(2), EtO: 1.39(3), 4.30q(2), H-3: 4 ,0s(1 ), H-15: 6.17s(1 ), Ar-H: 7.0-7.98m(8), NH: 7.30s(1).

EXAMPLE 24

Preparation of 2-hydroxyethyl-11-acetamidoapovincamate

A mixture containing 2.13 g (0.0054 mol) of 11-acetamidoapovincamine and 0.1 g of potassium tert-butoxide in 70 ml of ethylene glycol was stirred at 120°C for 90 minutes, after which the excess of ethylene glycol was removed by distillation under reduced Print. The residue was dissolved in 50 ml of ethyl acetate and was extracted three times, each time with 20 ml of water. The ethyl acetate phase was dried over anhydrous sodium sulfate, was filtered and the filtrate was evaporated to dryness under reduced pressure. The residue was triturated with 30 ml of ether, and the crystals obtained were washed with ether and dried to give 1.47 g (64% yield) of the desired compound, mp: 146-150°C.

<1>H-NMR spectrum (CDCl3, 6 ): Et: 0.98t(3), 1.82q(2), CH3CO:

2.16s(3), H-3 and CH2OCO: 3.85m(3), OCH2: 4.52m(2), H-15: 6.04, Ar-H: 6.7-7.8m(3 ), NH: 7.36s(1 ).

EXAMPLE 25

Preparation of 11-nicotinoylaminoapovincamine

A solution of 11.3 g of nicotinoyl chloride in 100 ml of anhydrous benzene was added dropwise to 4.0 g (0.011 mol) of 11-aminoapovincamine dissolved in 80 ml of pyridine with stirring. The mixture was stirred at room temperature for eight hours and then allowed to stand overnight. The solution was then evaporated to dryness under reduced pressure, the residue was dissolved in 100 ml of water and made alkaline to pH 8 by addition of a concentrated aqueous ammonium hydroxide solution. The precipitated product was filtered, washed with water and dried to give 4.00 g (80% yield) of the desired compound, mp: 148-152°C. /oi/d = +17.00° (c = 1, dichloromethane).

<1>H-NMR spectrum (CDCl3,6): Et: 1.00t(3), 1.90q(2), CH3O: 3.90s(1 ), H-1 5: 6.06s(1 ), ArH+NH: 7 , 2-8.93m(8).

EXAMPLE 26

Preparation of 11-(2-fluorobenzoylamino)-apovincamine

A mixture containing 9.5 g (0.019 mol) of 11-(2-fluorobenzoylamino)-vincamine and 20 g of p-toluenesulfonic acid in 500 ml of benzene was refluxed using a water trap for two hours and then cooled. After adding 200 ml of water, the pH was adjusted to 8 using concentrated aqueous ammonium hydroxide solution. After extraction and separation, the benzene layer was washed four times, each time with 100 ml of water, was dried over anhydrous sodium sulfate, filtered, whereupon the filtrate was evaporated to dryness under reduced pressure. After recrystallization of the residue from 300 ml of diisopropyl ether, 7.14 g (86% yield) of the desired product was obtained, m.p.: 102-105OC, /a/o= -2.40° (c = 1, dichloromethane) .

<1>H-NMR spectrum (CDCl3, 6): Et: 1.02t(3), 1.95q(2), CH3O:

4.01s(1), H-3: 4.30s(1), H-15: 6.18s(1), ArH: 6 , 95-8 , 00m(6 ) , H-12 : 7.92d( 1), 7.14dd and

8.22dd(1), NH: 8.45 and 8.62s(1), skeletal protons: 1 .00-3.4m(10).

EXAMPLE 27

Preparation of 11-(2-thiophenecarbonyl)-aminoapovincamine Method a)

A mixture containing 15.1 g (0.031 mol) of 11-(2-thiophenecarbonyl)-aminovincamine and 17 g of p-toluenesulfonic acid in 400 ml of benzene was refluxed using a water trap for two hours and then cooled. After adding 100 ml of water, the pH was adjusted to 8 using concentrated aqueous ammonium hydroxide solution. After extraction, the benzene phase was washed five times, each time with 50 ml of water, was dried over anhydrous sodium sulfate, filtered, whereupon the filtrate was evaporated to dryness under reduced pressure. After recrystallization of the residue from 100 ml of diisopropyl ether, 14.0 g (96% yield) of the desired product was obtained, mp: 138-140°C.

<1>H-NMR spectrum (CDC13,6 ): Et: 1.02t(3), CH3O: 3.98s(3),

H-3: 4.03s(1), H-1 5: 6.10s(1), A r H : 7.0-7.74m(6), NH: 8.05s(1).

Method b)

1.5 ml of dimethyl sulfate was added to a solution containing 6.7 g (0.015 mol) of 11-(2-thiophenecarbonyl)-aminoapovinicamic acid in 20 ml of acetone and 15 ml of 1N aqueous sodium hydroxide solution at room temperature and with stirring. After stirring for 90 minutes, 0.5 ml of concentrated aqueous ammonium hydroxide solution was added to the mixture which was then evaporated to half volume under reduced pressure. The precipitated substance was filtered, washed twice, each time with 10 ml of water, and was dried to give 6.5 g (95% yield) of the desired compound, whose physical properties were consistent with those of the product obtained by method a).

EXAMPLE 28

Preparation of 11-benzoylaminoapovincamine

A solution of 4.4 g (0.01 mol) of 11-benzoylaminoapovincinamic acid in 100 ml of anhydrous methanol was saturated with dry hydrogen chloride gas in the presence of a molecular sieve (3 Å, Aldrich 20, 859-2), after which the mixture was refluxed in five hours while hydrogen chloride was continuously bubbled into the solution. The solution was then evaporated to dryness, the residue taken up in a mixture of 100 ml ethyl acetate and 50 ml water, and made alkaline to pH 8 by the addition of a concentrated aqueous ammonium hydroxide solution. After separation, the ethyl acetate layer was washed twice, each time with 30 ml of water, was dried over anhydrous sodium sulfate, filtered, whereupon the filtrate was evaporated to dryness under reduced pressure. After recrystallization of the residue from 40 ml of a 1:1 mixture of diisopropyl ether and hexane, 3.9 g (86% yield) of the desired compound was obtained, m.p.: 129-132°C.

<1>H-NMR spectrum (CDCl3, 6 ): Et: 1.00t(3), CH3O: 4.00s(3),

H-3: 4.10s(1), H-15: 6.12s(1), ArH+NH: 7.08-8.15m(9).

EXAMPLE 2 9

Preparation of 2-hydroxyethyl-11-benzoylaminoapovincamate

A solution of 0.45 g (0.001 mol) of 11-benzoylaminoapovincamine in 10 ml of ethylene glycol was heated in the presence of 0.01 g of potassium tert-butoxide at 120°C for two hours and then evaporated to dryness under reduced pressure. The residue was dissolved in 25 ml of water, and was extracted twice, each time with 30 ml of ethyl acetate. The ethyl acetate solution was washed twice, each time with 10 ml of water, was dried over anhydrous sodium sulfate, filtered and the filtrate was evaporated to dryness under reduced pressure. After recrystallization of the residue from 8 ml of diisopropyl ether, 0.38 g (78% yield) of the desired compound was obtained, m.p.: 136-138QC.

<1>H-NMR spectrum (CDCI3,6 Et: 0.98t(3), H-3: 3.68s(1 ) , CH2OCO: 4.55m(2), H0-CH2: 3.80m(2) , H-15: 6.03s(1), ArH: 6 , 98-7.96m(8), NH: 8.32.

EXAMPLE 30

Preparation of 2-methylpropyl-11-benzoylaminoapovincamate mono-hydrochloride

A solution containing 0.8 g (0.0018 mol) of 11-benzoylaminoapovincamine and 0.01 g of potassium tert-butoxide in 20 ml of anhydrous isobutanol was refluxed for two hours and then evaporated to dryness under reduced pressure. The residue was dissolved in 40 ml of dichloroethane and was extracted four times, each time with 5 ml of water. The organic phase was dried over anhydrous sodium sulfate, filtered and the filtrate was evaporated to dryness. The residue (0.83 g, 93% yield) is the base form of the desired compound which was dissolved in 15 ml of ether and acidified to pH 3 by addition of an ethanolic hydrogen chloride solution. The precipitated crystals were filtered, washed with ether and dried to give 0.69 g (72% yield) of the monohydrochloride form of the desired compound, mp: 185-186°C.

Analysis

Calculated for C31H35N3O3•HC1 (molecular weight 534.07):

C 69.71, H 6.79, N 7.86, Cl 6.63%,

found: C 69.86, H 7.00, N 7.84, Cl 6.70%.

EXAMPLE 31

Preparation of 11-aminovincamic acid

A solution containing 2.5 g of potassium hydroxide in 20 ml of water was added to a solution of 2.5 g (0.007 mol) of 11-aminovincamine in 100 ml of ethanol whereupon the mixture was refluxed for 30 minutes. After cooling the solution to room temperature, the pH value was adjusted to 7 by adding 10% aqueous hydrochloric acid. The precipitated crystals were filtered, washed twice, each time with 10 ml of cold 50% ethanol, and were dried to give 2.0 g (83% yield) of the desired compound, mp: 255-256 °C, /ol/ q = +32.4°

(c = 1, pyridine).

EXAMPLE 32

Preparation of 11-(2-fluorobenzoylamino)-vincamic acid

A solution containing 0.30 g (0.0006 mol) of 11-(2-fluorobenzoylamino)-vincamine, 5 ml of ethanol and 3 ml of 10% aqueous potassium hydroxide solution was stirred at 35°C for 30 minutes, after which the pH of the mixture was adjusted to 7 by the addition of 10% aqueous hydrochloric acid. The precipitated crystals were filtered, washed three times, each time with 5 ml of water, and were dried to give 0.25 g (85% yield) of the desired compound, m.p.: 247-249°C, /a /o= +18.6° (c = 1, pyridine).

EXAMPLE 33

Preparation of 11-benzoylaminoapovicamic acid

To a solution containing 3.67 g (0.001 mol) of 11-nitroapovincinamic acid, 5 ml of ethanol and 10 ml of 1N aqueous sodium hydroxide solution, 0.04 g of a 10% palladium-on-carbon catalyst was added, after which the solution was stirred under a hydrogen atmosphere at room temperature. After absorption of 0.03 mol (720 ml) of hydrogen gas, the catalyst was removed by filtration and was washed three times, each time with 2 ml of 50% aqueous ethanol. After filtering and washing the catalyst, a solution of 3 ml of benzoyl chloride in 30 ml of acetone was added dropwise to the resulting solution at room temperature while the pH value of the reaction mixture was kept between 7 and 8 by adding 1N aqueous sodium hydroxide solution as needed. The mixture was stirred at room temperature for two hours after which the pH was adjusted to 7, the precipitated crystals were filtered, washed with water and dried to give 3.88 g (88% yield) of the desired compound whose physical properties were in agreement - agreement with those of the product produced in example 1.

EXAMPLE 34

Preparation of 11-cyclohexylaminovincamine

A solution of 1.46 g (0.01 mol) of cyclohexanecarboxylic acid chloride in 20 ml of anhydrous benzene was added portionwise over one hour to a solution containing 1.85 g (0.005 mol) of 11-aminovincamine in 80 ml of anhydrous pyridine at room temperature and with stirring. The solution was then stirred at room temperature for two hours and evaporated to dryness under reduced pressure. The residue was taken up in a mixture of 50 ml of ethyl acetate and 50 ml of water, and was made alkaline to pH 8 by the addition of concentrated aqueous ammonium hydroxide solution. The phases were separated, the ethyl acetate layer was washed three times, each time with 25 ml of water, was dried and evaporated to one third of its volume. The residue was allowed to stand in a refrigerator overnight, the crystals obtained were filtered off, washed with cold ethyl acetate and dried to give 1.67 g (70% yield) of the desired product, m.p.: 170-174°C.

EXAMPLE 35

Preparation of 11-(3'-bromopropionylamino)-apovincamine

A solution containing 1.71 g (0.01 mol) of 3-bromo-propionyl chloride in 30 ml of anhydrous benzene was added portionwise over one hour to a solution of 2.0 g (0.0055 mol) of 11-aminoapovincamine in 50 ml of anhydrous pyridine while stirring and while cooling with ice. The mixture was further stirred at room temperature for two hours and then evaporated under reduced pressure. The residue was taken up in a mixture of 50 ml of ethyl acetate and 50 ml of water, and was made alkaline to pH 8 by the addition of a concentrated aqueous ammonium hydroxide solution. After separation, the ethyl acetate phase was dried and evaporated to dryness. The residue was dissolved in 10 ml of methanol and precipitated by adding ether. The product obtained was filtered, washed with ether and dried to give 1.5 g (62% yield) of the desired compound, m.p.: 176-180°C.

EXAMPLE 36

Preparation of 11-cyclohexylaminoapovincamine

A mixture containing 4.79 g (0.01 mol) of 11-cyclohexylaminovincamine (prepared according to Example 34) and 5.5 g of p-toluenesulfonic acid in 220 ml of benzene was refluxed using a water trap for six hours and was then cooled whereupon 200 ml of water was added. The pH of the mixture was adjusted to 8 by adding a concentrated aqueous ammonium hydroxide solution. After extraction, the benzene phase was washed four times, each time with 100 ml of water, was dried over anhydrous sodium sulfate, whereupon the filtrate was evaporated to dryness under reduced pressure. After thorough trituration of the residue with ether, the crystals obtained were filtered and washed with ether to form 4.0 g (87% yield) of the desired compound, m.p.: 130-135°C.

Claims (6)

1. Process for the preparation of racemic and optically active 9- and 11-aminoeburnane carboxylic acid derivatives of general formula I in which R denotes an amino group; or denotes a -NH-COR1 group in which r<1> denotes a hydrogen atom, an optionally substituted C3-8 aliphatic, C3-8 alicyclic or C8-]4 aromatic hydrocarbyl group or a heteroaromatic group; or denotes a -NH-SC^ -R^ group, wherein R<2> denotes a optionally substituted Cj _^ q <a> liphatic or C 6-14 aromatic hydrocarbyl group; r <3> denotes a hydrogen atom, an optionally substituted Cj _^ q aliphatic group, a ^ 2-8 alicyclic or C 8 -^ aromatic hydrocarbyl group; A denotes a hydroxyl group; B represents a hydrogen atom; or A and B together form a valence bond; provided that r<3> is different from methyl group when R denotes an amino group or a -NH-COR^ group in the 11-position, wherein R^ is a methyl group, A denotes a hydroxyl group and B denotes a hydrogen atom; and r <3> is different from hydrogen atom when R denotes an amino group and A and B together form a valence bond, as well as their salts, characterized in that a racemic or optically active 9- or 11-aminoeburnane carboxylic acid derivative of general formula II or a salt thereof, in which R <4> denotes a methyl group and, when A and B together form a valence bond, can also denote a hydrogen atom, acylated, optionally after hydrolysis, after which, if desired, the thus obtained 9- or 11-aminoeburnanecarboxylic acid derivative of general formula I in which R denotes a -NH-COR <1-> or NH-SC^R^ group in which R^ and R <2> are as defined above, r <3> and R<4> are identical, and A and B is as defined for formula I esterified or if desired transesterified, and if desired, that a racemic or optically active 9- or 11-aminoeburnane carboxylic acid derivative of general formula I in which R denotes a -NH-COR^- or -NH-SG^R^ group in which R^ is as defined above, A denotes a hydroxyl group, B denotes a hydrogen atom and R^ denotes an optionally substituted _^q aliphatic, C^_g alicyclic or ^6 — 14 aromatic hydrocarbyl group is hydrolyzed or first esterified, or if desired transesterified, and if desired, that a racemic or optically active 9- or 11-aminoeburnanecarboxylic acid derivative of general formula I in which R denotes an amino group, R^ denotes an optionally substituted Cj_^q aliphatic, C^_g alicyclic or Cg_-| 4 aromatic hydrocarbyl group, A denotes a hydroxyl group and B denotes a hydrogen atom, is hydrolysed, after which, if desired, the thus obtained racemic or optically active 9- or 11-aminoeburnanecarboxylic acid derivative of general formula I in which R denotes an amino group and R^, A and B are as defined above is acylated, after which, if desired, a racemic or optically active 9- or 1 1-aminoeburnanecarboxylic acid derivative of general formula I in which R and R- <3> are as defined above, A denotes a hydroxyl group and B denotes a hydrogen atom, is dehydrated, and if desired, that a thus obtained racemic or optically active 9- or 11-aminoeburnane carboxylic acid derivative of general formula I in which R, R<3> , A and B are as defined for general formula I, is converted into an acid addition salt and/or into a quaternary salt and/or that a thus obtained racemic product dissolves. 2. Method according to claim 1, characterized in that the acylation is carried out using an organic acid or sulphonic acid or with a functional derivative such as a halide or an anhydride. 3. Method according to claim 1, characterized in that the esterification is carried out directly with an excess of an alcohol, or indirectly by using the suitable halide or sulphate in the presence of a base. 4. Method according to claim 1, characterized in that the hydrolysis is carried out in the presence of a base. 5. Method according to claim 1, characterized in that the dehydration is carried out in the presence of a carbodiimide-type dehydrating agent. 6. Process according to claim 1, for the production of racemic and optically active compounds 11-benzoylaminoapovincinamic acid, 9-benzoylaminoapovincinamic acid, 11 -(2-thiophenecarbonylamino)-apovincamic acid, 9-(2-thiophenecarbonylamino)-apovincamic acid, ethyl 11-aminoapovincamate ethyl-9-aminoapovincamate, ethyl-11-methylsulfonylaminoapoviricamate and the monohydrochloride thereof, ethyl 9-methylsulfonylaminoapovincamate and its monohydrochloride, ethyl 11-aminovincamate ethyl 9-aminovincamate, methyl-11-(4-nitrobenzoylamino)-apovincamate, methyl-9-(4-nitrobenzoylamino)-apovincamate, methyl-11-(2-bromobenzoylamino)-apovincamate and its monohydrochloride, methyl-9-(2-bromobenzoylamino)-apovincamate and its monohydrochloride, 11-(2-Fluorobenzoylamino)-vincamine, 9-(2-Fluorobenzoylamino)-vincamine, 11-(3,4,5-trimethoxybenzoylamino)-vincamine, 9-(3,4,5-trimethoxybenzoylamino)-vincamine, 11- pivaloylaminovincamine, 9-pivaloylaminovincamine, 9-benzoylaminovincamine, 11-benzoylaminovincamine, 9-acetamidovincamine, 11-acetamidovincamine, 11 -(2-thiophenecarbonylamino)-vincamine, 9-(2-thiophenecarbonylamino)-vincamine, 11 -(2-thiophenacetylamino)-vincamine, 9-(2-thiophenacetylamino)-vincamine, 9-acetamidoapovincamine, 11-acetamidoapovincamine, 11 -(3,4,5-trimethoxybenzoylamino)-apovincamine, 9-(3,4,5-trimethoxybenzoylamino)-apovincamine, 11-pivaloylaminoapovincamine ethyl-9-benzoylaminovincamate, ethyl-11-benzoylaminovincamate, ethyl-9-benzoylaminoapovincamate, ethyl -11-benzoylaminoapovincamate, 2-hydroxyethyl-11-acetamidovincamate, 2-hydroxyethyl-9-acetamidovincamate, 11-nicotinoylaminoapovincamine, 9-nicotinoylaminoapovincamine, 11 -(2-fluorobenzoylamino)-apovincamine, 9-(2-fluorobenzoylamino)-apovincamine, 11 -(2-thiophenecarbonylamino)-apovincamine, 9-(2-thiophenecarbonylamino)-apovincamine, 11-benzoylaminoapovincamine, 9-benzoylaminoapovincamine, 2-hydroxyethyl-11-benzoylaminoapovincamate, 2-hydroxyethyl-9-benzoylaminoapovincamate, 2-methylpropyl-11-benzoylaminoapovincamate and its monohydrochloride, 2-methylpropyl-9-benzoylaminoapovincamate and its monohydrochloride, 11-aminovincamic acid, 9-aminovincamic acid, 11 -(2-fluorobenzoylamino)-vincamic acid and 9-(2-fluorobenzoylamino)-vincamic acid.