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39. Novel methods for the synthesis of 2-[(4 R)-2-oxo-4-phenylpyrrolidin-1-yl]-acetamide (( R)-phenotropil).

Author

Vorona, M., Veinberg, G., Vikainis, S., Kuznetsov, E., Lebedev, A., Ponomarev, Yu., Chernobrovijs, A., Zvejniece, L., and Dambrova, M.

Subjects
ORGANIC synthesis, PYRROLIDINE, ACETAMIDE, POTASSIUM phosphates, TOLUENE, AMMONIUM bromide
Abstract

Two novel methods have been developed for the preparation of 2-[(4 R)-2-oxo-4-phenylpyrrolidin-1-yl]acetamide (( R)-Phenotropil). In the first, n-butyl (3 R)-4-amino-3-phenylbutyrate is alkylated with haloacetamide in DMF in the presence of potassium phosphate monohydrate, and the intermediate 4-carbamoylmethylamino-3-phenylbutyrate is subsequently cyclized by refluxing in toluene in the presence of potassium phosphate monohydrate and tetrabutylammonium bromide. In the second, chloroacetonitrile is used under similar conditions in place of the haloacetamide. Both methods lead to ( R)-Phenotropil in 40-60% yields calculated on the starting n-butyl (3 R)-4-amino-3-phenylbutyrate. [ABSTRACT FROM AUTHOR] more...

Published
2012
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40. Synthesis and cytotoxic activity of derivatives of 6 Z-acetylmethylenepenicillanic acid tert-butyl ester.

Author

Vorona, M., Potorochina, I., Veinberg, G., Belyakov, S., Shestakova, I., Kanepe, I., and Lukevics, E.

Subjects
SULFOXIDES, PENICILLANIC acids, SULFONES, HYDROXYLAMINE, ANTINEOPLASTIC agents, ISOMERISM
Abstract

The sulfoxide of 6 Z-[2-(methoxyimino)propylidene]penicillanic acid tert-butyl ester and the sulfones of 6 Z-[2-(hydroxyimino-, methoxyimino-, benzyloxyimino-, 2-bromo- and 4-bromobenzyloxyimino)-propylidene]penicillanic acid in the syn and anti forms have been synthesized by the condensation of the sulfoxide and sulfone of 6 Z-acetylmethylenepenicillanic acid tert-butyl ester with hydroxylamine, methoxyamine, benzyloxyamine, 2-bromo- and 4-bromobenzyloxyamines. The syn and anti isomers of 3 Z-(2-methoxyiminopropylidene)-4 R-(benzothiazolyl-2-dithio)-2-oxoazetidinyl-1 R-(2-propenyl)acetic acid tert-butyl ester were obtained by opening of the thiazolidine ring in 6 Z-[2-(methoxy-imino)propylidene]-1-oxopenicillanic acid tert-butyl ester with 2-mercaptobenzothiazole. The 3 Z-(2-methoxyiminopropylidene)-4 R-(methylsulfonyl)-2-oxoazetidinyl-1-(2-propylidene)acetic acid tert-butyl ester was synthesized by the interaction of 1,8-diazobicyclo[5.4.0]undec-7-ene and methyl iodide with 6 Z-[2-(methoxyimino)propylidene]-1,1-dioxopenicillanic acid tert-butyl ester. A dependence of the cytotoxic effect in relation to cancer and normal cells in vitro on the structure of the substituent in position 6 and the syn and anti isomerism of the oxyimino group was established for the synthesized compounds. [ABSTRACT FROM AUTHOR] more...

Published
2009
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41. Synthesis and cytotoxic activity of derivatives of the tert-butyl ester of 7 Z-acetylmethylene-3-methyl-3-cephem-4-carboxylic acid.

Author

Potorocina, I., Vorona, M., Veinberg, G., Shestakova, I., Kanepe, I., Petrova, M., Liepinsh, E., and Lukevics, E.

Subjects
ANTINEOPLASTIC agents, CARBOXYLIC acids, CONDENSATION, HYDROXYLAMINE, CHEMICAL reactions, ESTERS, CELLS
Abstract

The condensation of the acetylmethylene group in the tert-butyl esters of 7 Z-acetylmethylene-3-methyl-3-cephem-4-carboxylic acid and 7 Z-acetylmethylene-3-methyl-1,1-dioxo-3-cephem-4-carboxylic acid and in 7 Z-acetylmethylene-3-methylene-1,1-dioxo-3-cephem with arylmethoxyamines and O-alkylation of the tert-butyl ester of 7 Z-(2-hydroxyimino)propylidene-3-methyl-1,1-dioxo-3-cephem-4-carboxylic acid using substituted benzyl bromides as well as pyridylmethyl chlorides gave arylmethoxyimino and pyridylmethoxyimino derivatives of these compounds in the syn and anti isomeric forms. The Vilsmaier reagent was used to introduce the N,N-dimethylaminomethylene group at C-2 of the cephem system in the tert-butyl esters of 7 Z-[2-(arylmethoxyimino)propylidene]-3-methyl-1,1-dioxo-3-cephem-4-carboxylic acid. Subsequent transformation of the N,N-dimethylaminomethylene cephems using hydroxylamine led to 3 Z-[2-(anti-arylmethoxyimino)propylidene]- tert-butoxycarbonylmethyl-4-(5-methyl-4-isoxazolylsulfonyl)- azetidin-2-ones. Condensation of the acetyl group in the tert-butyl ester of 7 Z-acetylmethylene- 3-methyl-1,1-dioxo-3-cephem-4-carboxylic acid with 4-bromophenylhydrazine gave a cephem with a 2-(4-bromophenylhydrazono)propylidene group at C-7. Acylation of the tert-butyl ester of 7 Z-(2-hydroxyimino)propylidene-3-methyl-1,1-dioxo-3-cephem-4-carboxylic acid by 2-bromobenzoyl chloride gave a cephem with a 2-(2-bromo-benzoyloxyimino)propylidene group at C-7. Biological screening of these products towards to malignant and normal cells in vitro showed that their antitumor activity and cytotoxic selectivity towards to malignant and normal cells depend on the structure and configuration of the arylmethoxyimino and pyridylmethoxyimino groups in the 7-alkylidene substituent as well as on the presence or absence of N,N-dimethylaminomethylene and carboxyl groups, respectively, at C-2 and C-4 of the cephem system. [ABSTRACT FROM AUTHOR] more...

Published
2009
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