Process for producing optically active benzene-sulfonamide derivatives

Abstract From the Canadian patent

The present invention is directed to processes for producing optically active benzenesulfonamide derivatives useful as antihypotension agents and intermediates of optically active drugs. The optically active benzenesulfonamide derivates are represented by the general formula (I) (see fig. I), (wherein R1 and R2 are same or different hydrogen atom or a lower alkyl group; R3 denotes hydrogen atom, a lower alkyl hydroxyl or a, lower alkoxyl group; and R4 stands for a lower alkyl group). The processes comprise either decomposing a m-(2-substitutedalkylaminoalkyl)benzenesulfonamide derivative represented by the general formula (II), (see fig. II), (wherein R1 R2, R3 and R4 are as defined above; …