BENZOTHIAZIN DERVATIVES AND THEIR PREPARATION

摘要

Benzothiazine derivs. of formula (I) are prepd. by (a) reacting a cpd. of formula (II) with mCPBA to obtain sulfoxide cpds. of formula (III); (b) hydrolyzing (III) to obtain carboxylic acid cpds. of formula (IV); and (c) forming amine cpds. of pyrrolidine or piperazine of formula (I) by the neucleophyllic substitution reaction. In the formulas, R= piperazinyl opt. substd. by C1-6 alkyl; R'= C1-3 alkyl (I) have antibacterial activity.