SU731900A3 - Method of prepaping vinblastin derivatives - Google Patents

Abstract

1463575 Novel amides, azides and hydrazides of vinca alkaloids ELI LILLY & CO 25 March 1974 [2 April 1973] 13101/74 Heading C2C Novel compounds of the Formula I wherein R is NH 2 , NH.NH 2 , N(CH 3 ) 3 , NHalk-X, NH(C 3-8 )cycloalkyl, NHalkAm, NHalk(OH) 1-3 or N 3 ; wherein alk is C 1-6 alkylene, Am is NH 2 , NHCH 3 or N(CH 3 ) 2 , X is hydrogen, CN, optionally substituted phenyl, carboxy, carbo- (C 1-3 )-alkoxy, or carboxamido; R<SP>1</SP> is H, alkanoyl or chloroalkanoyl; R<SP>11</SP> is hydrogen, C 1-3 alkyl, formyl or alkanoyl; and one of R<SP>111</SP> and R<SP>1111</SP> is hydroxy and the other is ethyl, in which alkanoyl groups have 1-3 carbon atoms in the alkane moiety, and salts thereof, may be prepared by reacting a compound of the Formula I wherein R is OCH 3 , R<SP>1</SP> is hydrogen or acetyl and R<SP>11</SP>, R<SP>111</SP> and R<SP>1111</SP> are as defined above with ammonia, methylamine or hydrazine to obtain a compound of Formula I wherein R is NH 2 , NHCH 3 or NH.NH 2 , and R<SP>1</SP> is hydrogen and, if desired, when R is NHNH 2 (a) reacting said compound with a nitrosating agent to form an azide in where R 3 N 3 and then reacting said azide with ammonia, an amine of the formula HN(CH 3 ) 2 , NH 2 alk-X, NH 2 -(C 3-8 )cycloalkyl, NH 2 alkAm or NH 2 alk(OH) 1-3 to obtain the corresponding compound of Formula I or (b) hydrogenolysing said compound with Raney nickel in an inert solvent to yield a compound of the Formula I wherein R is NH 2 , and/or, if desired, acylating a product in which R<SP>1</SP> is hydrogen to introduce an alkanoyl or chloroalkanoyl group at R<SP>1</SP>, and, if in the starting material R<SP>11</SP> is hydrogen, to introduce an alkanoyl or chloroalkanoyl at R<SP>11</SP>. Various by-products having the same ring systems as I are formed during some of the above reactions. Pharmaceutical compositions of the compounds I or salts thereof with the usual excipients may be administered orally or parenterally for treating neoplastic disease. The compounds also show antivral activity in vitro against herpes virus.

Description

The invention also relates to a method for producing derivatives of vinblastine not described in the literature with the general formula A -CHt-CHj where R is an amino, hydraziko, is an azido or methylamino group; R is hydrogen or C – C apan; R is hydrogen or C – C apkyl — hydroxy; R is ethyl with pharmacological activity. A known method for producing carboxylic acid amides is that the carboxylic acid ester is reacted with ammonia or amines 1. Using a known reaction, vinblastine derivatives of the general formula A, not described in the literature, are obtained. Purpose of the invention is a method for preparing new pharmacologically active vinblastine derivatives General Formula A. The goal is to be achieved by the described method for the preparation of vinblastine derivatives of General Formula A, concluding that the compound of the general form A, where R is a methoxy group, R, R, R, and R are aforementioned, are reacted with a compound of the general formula RH, where R is amino, is a hydrazino, azido or methylamino group, in anhydrous methanol or ethanol at 50-100 ° C . If necessary, the compound of general formula A, where R is a hydrazino group, is nitrosated to form a compound of general formula A, where R is an azido group.

The desired compounds of formula L are isolated and separated by known methods.

Derivatives of vinblastine of the general formula A possess antiviral and antitumor activity.

When I mr 1. Vinblastin-C-ZY-methylcarboxamide and 4-deacetylvinblastin-C-3M-methylcarboxamide,

About 3.5 g of vinblastine is added to a solution of 21 g of methylamine in 100 ml of anhydrous methanol at -78 ° C and left for 8 days at 50 ° C, then the volatile components are removed by evaporation in vacuo. According to the nuclear magnetic resonance (NMR) spectrum and the infrared spectrum, the residue is a mixture of 4-deacetylvinblastine-C3H3 methylcarboxamide and 4-deacetylvinylblastine. This residue is dissolved in. 100 ml of pyridine and 20 ml of acetic anhydride are added, left for 18 h, then evaporated in vacuo. The residue obtained is chromatographed on alumina using a mixture of ethyl acetate and chloroform (1: 1) for elution. The fractions containing vinblastine-C-3H-methylcarboxamide are combined and the solvent is removed by evaporation in vacuo.

With the acetylation procedure described above, not only C-4-hydroxyl is reacetylated, but C-3-hydroxyl is also acetylated. The acetyl group at C-3 is removed by treating with silica gel in aqueous methanol at room temperature for a period of from 6 hours to several days and a product is obtained which does not contain a C-3 acetyl group. In this case, the residue of the combined chromatographic fractions is dissolved in 50 ml of methanol and 20 ml of water and 2 g of silica gel are added to the solution. The mixture is filtered, the filtrate is evaporated to dryness in vacuo, and the residue is chromatographed on silica gel. A mixture of benzene, chloroform and triethylamine (100: 50: 7.5) is used for the elution. I select the fractions containing the desired vinblastine-C-ZY-methylcarboxamide. The solvent is removed by evaporation in vacuo. The residue is dissolved in aqueous methanol and adjusted to pH 2.9 with the addition of 1% acid. After evaporation of the resulting mixture in vacuo, the winnastast-C-3X3-methylcarboxamide sulfate is obtained, which, after recrystallization from anhydrous ethanol, has a melting point of 272-275 ° C (with decomposition).

4-deacetylvinblastin-C-3SY-methylcarboxamide is isolated from the mixture with 4-β-deacetylvinblastine obtained in the amidation step, followed by methods.

The residue obtained upon evaporation of the initial (before recrystallization) reaction mixture to dryness in vacuo was chromatographed on silica gel, using a mixture of benzene, chloroform and triethyl amine, mentioned above, to elute. The fractions containing 4-deacetylvinblastin-C- -ZY-methylcarboxamide, as determined by thin layer chromatography, are combined, the solvent is evaporated in vacuo, and the N-methylcarboxamide is obtained as amrph solid. Sulfate 4-dezatsetilvinblastin-C-ZY-methylcarboxamide receive according to the method described for the preparation

5 sulfate vinblastine-C-ZY-methylcarboxamide.

According to the procedure described above, 2 g of 4-deacetylvinblastin is dissolved in a mixture of 75 ml of anhydrous methanol.

0 and 20 g of ethylamine. The reaction mixture is heated at about 8 days. The resulting 4-deacetylvinblastin-C-3S-ethylcarboxamide is separated by the method

with chromatography in a thin layer. The obtained solid has a band at 1670 cm in the infrared spectrum characteristic of the substituted carboxamide.

EXAMPLE 2. 4-Desacetyl Vin-tent-C-3-carboxamide.

Approximately 10 g of vinblastine sulfate is converted in the usual manner into the free base of vinblastine. This base, obtained as a residue after evaporation of the ether, is dissolved in about 200 ml of anhydrous methanol. Anhydrous liquid ammonia (300 ml) is added to the solution, the reaction mixture is maintained at a temperature of about 100 ° C for 60 hours. It is then evaporated in vacuo. The residue obtained is chromatographed and the fractions containing 4-deacetylvinblast-C-3-car. Boxamide, as shown by fine layer chromatography, are combined, the solvent is evaporated in-vacuum and the pure free base is obtained in the form of 4-deacetyl-winblastin-C-3-carboxamide. . Freebing has a band in the infrared spectrum of 1687, characteristic of the amide group. The molecular weight of the free base, as determined by mass spectroscopy, is 753, which is the same as the calculated theoretical value for,.

600 mg of the residue is converted to the sulfate in the conditions of Example 1. When the reaction mixture is evaporated to dryness, 4-deacetylvinblastine 0-C – 3-C-carboxamide sulfate is obtained, which, after recrystallization from a mixture of ethanol and isopropyl alcohol, melts (with decomposition,

4-deacetylvinblastin-C-3-carbox 5 amide is converted into vinblastine-C-3-; carboxamide according to the method of example 1 as follows. 2.8 g of the free base of 4-deacetylvinblastin-C-3-carboxamide is acetylated with a mixture of anhydrous pyridine and acetic anhydride, and the reaction mixture is kept for three days at room temperature. After removing the volatile components by evaporation in vacuo, a residue is obtained, which is dissolved in methylene chloride. The solution is washed with water, dried and evaporated to dryness. Vinblastine-C-3-carb6xamide is obtained. The amide is purified by chromatography on silica gel. A mixture of ethyl acetate and ethanol (1; 1) is used for elution. Fractions containing vinblastin-C-3-carboxamide, as indicated. chromatography on a thin layer is combined, the solvent is evaporated and the free base of vinblastine-C-3-carboxamide is obtained as a residue. This base has an amide-specific band in the infrared spectrum of about 1700 CM. The molecular weight, determined by mass spectroscopy, is 795, i.e. it coincides with the theoretical value calculated for C45H57 50. Vinblastine-2-3-carboxamide sulfate is obtained by the method described in example 1, and crystallized from ethanol; t.pcs above 250 C. froze. 4-desacetylvinblastin-C-3-carboxyhydrazide. According to the procedure of Example 1, 4-designation of tilvinblastin is heated in anhydrous ethanol with an excess of anhydrous hydrazine at a temperature of about 60 ° C for about 18 hours, then the volatile components are evaporated in vacuo. The resulting residue, consisting of 4-deacetylvinblastin-C-3-carboxyhydrazide, is dissolved in methylene chloride. This solution is shed with water, separated and methylene chloride is removed by evaporation in vacuo. The residue is dissolved in a mixture of chloroform and bezol (1: 1) and chromatographed on silica gel. A mixture of benzene, chloroform and triethylamine, mentioned in Example 1, is used for zonation. The initial chromatographic fractions contain unreacted 4-deacetylvinblastin. Subsequent fractions contain 4-desacetyl-18-descar-6-methoxy-vinblastin-C-3-carboxyhydrazide. The following fractions containing 4-deacetylvinblastin-C-3-carb oxyhydrazide, as determined by thin layer chromatography, are combined and the solvent is removed from them by evaporation in vacuo. The resulting solid melts at 210-220 ° C (with decomposition). The 4-deacetylvinblastin-C-3-car6oxy-hydrazide thus obtained has an absorption band of carbmethoxy in the infrared spectrum at 1725-1735 and a 1690 cm band due to the hydrazide function. The molecular weight, as determined by mass spectrography, is 768, which corresponds to the theoretical value calculated for C4jHj N O.,. Example 4. 4-Desacetylvinblastin-C-3-carboxazid. A solution of 678 ml of 4-deacetylvinblastin-C-3-carboxyhydrizide (example 3) and 15 ml of anhydrous methanol is mixed with 50 ml of 1N hydrochloric acid and the resulting solution is cooled to about 0 ° C. Then about 140 mg of sodium nitrite is added and the reaction mixture is stirred for 10 minutes, maintaining the temperature at about. By adding 140 mg of sodium nitrite and stirring for 10 minutes at p ° C, the solution becomes dark reddish-brown. The reaction mixture is then basified with an excess of cold 5% aqueous sodium bicarbonate solution and extracted three times with methylene chloride. 4-deacetyl vin blast: in-C-3-carboxazide formed in this reaction; dissolved in methylene chloride. Typically, a solution of 4-deacetylvinblastine-C-3-carboxazide in methylene chloride is used without further purification and an aliquot is treated in a manner to identify the azide. By evaporation of methylene chloride, the azide is obtained in an amorphous state. This residue is washed with ether and the suspension obtained is filtered. Residue in powder form. chew brown color has the following physical properties: ultraviolet spectrum L „dts 269 mmk (6" 16700); the shoulder is about 290-309 microns ("7100); the absorption maximum in the infrared spectrum at 1690 (carboxyhydrazide) is absent; the maximum at 1730 cm does not change. In addition, there is a pronounced maximum at 2135, characteristic of the carboxamide function. In the mass spectrum, a Tyuclear ion of t / e 708 is observed, proving a loss of 71 mass units (H, CONj) from the molecular weight calculated for C sHssN O 799. In the table below, the azanes are the results of several experiments in which compounds with the formula A are administered to transplanted tumors. ROS means osteogeous Ridge's sarcoma and GLS Gardner's lymphosarcoma, CA 755 adenosarcoma. Compounds of Formula A, dosage for mice at doses greater than those with KOT01MLK, 100% inhibition of growth of transplanted tumors occurs.

The compounds of formula A are also active against other transplanted tumors. For example, with an injection of 0.25 mg / kg for 9 days of vinblastine-C-3S-methylcarboxamide sulfate for the treatment of Mecca lymphosarcoma, growth was slowed by 54%, and with vinblastine-C-3 injection by 28%.

When studying the activity with respect to the ademocarcinoma CA 755, it was established that 4-deacetylvinblastine-S-3-carboxamide sulfate gave 75% tumor growth retardation, 61% deacetylvinblastine-S-ZY-methylcarboxamide sulfate 61% and vinblastine-C-3-carboxamide sulfate 49% at a dose of 0.25 mg / kg for 8 days and 72% at a dose of 0.3 mg / kg.

Claims (1)

The claims 30 1. A method of obtaining derivatives of vinblastine of the general formula A where R d ’ is an amino, hydrazino, azido or methylamino group? - hydrogen or C 4 - C 3 alkanoyl R - is hydrogen or a C4 - C ₃ alkyl; R * 'is an oxy group; R is ethyl, with the exception that the compound of general formula A, where R is a methoxy group, R *, R *, R ', and R' * 'have the above meanings, is reacted with a compound of the general formula RH, where R is an amino, hydrazino or methylamino group, in anhydrous methanol or ethanol at 50-100 ° C and, if necessary, a compound of the general formula A, where R is a hydrazine group, nitrosate to obtain a compound of the general formula A, where R is an azido group, after which the desired products are isolated.