3-OXO-1,4-BENZOTHIAZIN-DERIVATE

摘要

A compound represented by general formula (I), which is useful as a cataract remedy, wherein R<1> represents optionally protected hydroxy; R<2> represents lower alkyl; R<3> represents hydrogen, lower alkyl, optionally protected hydroxy or lower alkoxy, provided that the lower alkyl may be substituted by optionally protected hydroxy, amino or lower alkylamino; R<4> represents carboxyl which may be in the form of ester or carboxamide; and A represents alkylene.