| abstract |
A process for producing optically active benzenesulfonamide derivative (I) <CHEM> which comprises decomposing m-(2-substituted-alkylaminoalkyl)benzenesulfonamide derivative (II) <CHEM> wherein R<1> and R<2> are selected independently from a hydrogen atom and C1-C5 alkyl groups; R<3> is a hydrogen atom or a C1-C5 alkyl, hydroxyl or C1-C5 alkoxyl group; R<4> is a C1-C5 alkyl group; R<5> is a C1-C5 alkyl, carboxy-(C1-C5 alkyl) or (C1-C5 alkoxy)carbonyl-(C1-C5 alkyl) group; and R<6> is a substituted or unsubstituted phenyl, carboxyl or (C1-C5 alkoxy)carbonyl group. The compound of formula (II) are obtained by reacting a ketone of formula (III) <CHEM> x |