GB896303A - Improvements in and relating to sulphonylureas and the manufacture thereof - Google Patents

Abstract

The invention comprises sulphonyl ureas of the formula <FORM:0896303/IV (b)/1> in which A is an alkyl group of 1-3 carbon atoms, e.g. methyl, ethyl or isopropyl, or a methoxy group or a halogen atom, e.g. Cl or F, and R1 and R2 together form a 5 or 6 carbon atom, straight or branched, alkylene chain such as pentamethylene, hexamethylene or 1-methylpentamethylene, and salts thereof. The products are prepared by known methods for the preparation of sulphonyl ureas, e.g. by (a) reacting an arylsulphonyl isocyanate, an arylsulphonyl carbamoyl chloride or an N-alkoxycarbonyl-arylsulphonamide with an amine HNR1R2; (b) reacting an N1-unsubstituted arylsulphonyl urea or an N : N1-bis-(arylsulphonyl)-urea with an amine HNR1R2 and decomposing the resulting salt, or (c) reacting an arylsulphonyl chloride with an N-disubstituted-O-alkyl-isourea and hydrolysing the resulting N-arylsulphonyl-O-alkyl-isourea. Arylsulphonyl carbamates. The ethyl esters of p - methyl - and p - isopropyl - benzenesulphonyl - carbamic acids are made by the action of ethyl chloroformate on the arylsulphonamide. Arylsulphonyl isocyanates p-Methoxy-, p-chloro-and p-fluoro, benzenesulphonyl isocyanates are made by the action of silver cyanate on the arylsulphonyl chloride. Pharmaceutical preparations having hypoglycaemic activity comprise the above sulphonyl ureas in known pharmaceutical forms, such as tablets or solutions. The Provisional Specification also describes products wherein NR1R2 is a pyrrolidino group.