GB781418A - New sulfonamides - Google Patents

Abstract

The invention comprises 5-acylimino-4-substituted - D 2 - 1:3:4 - thiadiazoline - 2 - sulphonamides of the formula <FORM:0781418/IV (a)/1> wherein R1 is hydrogen, an alkyl group of 1-6 carbon atoms or a monocyclic aralkyl group and R2 is an alkyl group of 1-6 carbon atoms or a monocyclic aralkyl group. The compounds are made by reacting a 5-acylamino-4 - substituted - 2 - benzylmercapto - D 2 - 1:3:4-thiadiazoline with chlorine, for example by passing chlorine gas through a suspension or solution of the thiadiazoline in aqueous acid, such as 10 per cent aqueous acetic acid, and treating the resulting sulphonyl chloride with ammonia to give the desired sulphonamide. Examples describe the preparation by the above methods of 5 - acetylimino - 4 - benzyl -, 5-acetylimino - 4 - ethyl -, 5 - propionylimino-4 - methyl -, 5 - propionylimino - 4 - ethyl - and 5 - acetylimino - 4 - methyl -, D 2 - 1:3:4-thiadiazoline - 2 - sulphonamides; by similar methods the corresponding 5-formylimino-4-methyl -, 5 - butyrylimino - 4 - methyl -, 5-butyrylimino - 4 - benzyl -, 5 - acetylimino - 4-butyl - and 5 - propionylimino - 4 - butyl derivatives may be prepared. Starting materials. The 5-acylimino-4-substituted - 2 - benzylmercapto - D 2 - 1:3:4-thiadiazolines used as starting materials may be prepared by alkylating or aralkylating the corresponding 2 - acylamino - 5 - benzylmercapto-1:3:4-thiadiazoles with an alkyl or aralkyl halide, preferably in the presence of a sodium alkoxide. Specification 687,760 is is referred to.