1,4-Benzothiazine-2-acetic acid derivatives, processes for production thereof and their use.

摘要

1,4-Benzothiazine-2-acetic acid derivatives represented by general formula (I) below: <CHEM> wherein R<1> represents a group shown by general formula (II) or (III): <CHEM> wherein R<5> and R<6>, which may be the same or different, each represents hydrogen, a halogen atom, a lower alkyl group, a lower alkoxyl group, trifluoromethyl or cyano; <CHEM> wherein R<7>, R<8>, R<9> and R<1><0>, which may be the same or different, each represents hydrogen, a halogen atom, a lower alkyl group, a lower alkoxyl group or trifluoromethyl ; R<2> and R<3>, which may be the same or different, each represents hydrogen, a halogen atom, a lower alkyl group, a lower alkoxyl group, a lower alkylthio group, trifuloromethyl or trifluoromethoxy; R<4> represents carboxyl which may optionally be esterified; and X represents oxygen or sulfur; and processes for production thereof, as well as a composition for the treatment of complications associated with diabetes and an aldose reductase inhibitor comprising the same.