RU2223266C1 - Method for preparing anticonvulsant agent "beprodon" - Google Patents

Abstract

FIELD: medicine, chemical-pharmaceutical industry and technology, pharmacy. SUBSTANCE: invention relates to method for preparing an anticonvulsant preparation representing 3-benzylamino- Methylenepyrrolidine-2,4-dione (I). Method for preparing involves acylation of aminoacetic acid esters with malonic acid monoester chloroanhydrides in the presence of chloroform as a solvent. Prepared product is converted to 3-alkoxycarbonylpyrrolidine-2,4-dione in alcohol solvent in the presence of sodium alcoholate as cyclizing agent. Prepared product is decarboxylated by three-fold boiling with acetonitrile in the concentration of product (V) 20-30 g/l in reaction mixture followed by cooling, filtration and acetonitrile distillation off. Prepared pyrrolidine- -2,4-dione is added to reaction with corresponding dimethylformamide dialkylacetal or trialkoxymethane and prepared product is treated with benzylamine at 0-5 C followed by isolation of the end product. Method provides elevating yield of the end product without additional purification stages and to provide higher purity degree of preparation. EFFECT: improved preparing method. 3 cl, 2 ex

Description

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Claims (2)

1. The method of obtaining the drug, which is a 3-benzylaminomethylene pyrrolidin-2,4-dione (1), with anticonvulsant activity, characterized in that the aminoacetic acid esters are acylated with malonic acid monoesters in the presence of chloroform as solvent, the resulting product (IV) is converted in 3-alkoxycarbonylpyrrolidinedione-2,4 (V) in an alcoholic solvent in the presence of sodium alkoxide as the cyclizing agent, decarbalkoxylated (V) by boiling three times with acetonitrile at a concentration of kta (V) 20-30 g / l in the reaction mixture, followed by cooling, filtration, distillation of acetonitrile, the resulting pyrrolidin-2,4-dione is reacted with the corresponding dialkyl acetal of dimethylformamide or trialkoxymethane, after which the resulting product is treated with benzylamine at 0- 5 ° C followed by isolation of the target product. 2. The method according to claim 1, characterized in that the product obtained 3-benzylaminomethylene pyrrolidin-2,4-dione is subjected to recrystallization from 85% aqueous acetone in a ratio of 1: 4. The method according to claims 1 and 2, characterized in that the obtained target product is mixed with pharmaceutically acceptable excipients.

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