Condensed tricyclic compounds having aldose reductase inhibitory activity

摘要

A fused tricyclic compound having aldose reductase inhibitory activity and shown by the following formula, wherein R 1 independently represents 1 to 3 atoms or substituents selected from a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl, cycloalkyl, alkylene, or alkoxy group, and a protected or unprotected hydroxyl or carboxyl group, R 2 represents a protected or unprotected carboxyl group, R 3 independently represents 1 or 2 atoms or substituents selected from a hydrogen atom, a halogen atom, an oxo group, a substituted or unsubstituted alkyl or alkoxy group, and a protected or unprotected carboxyl group, A represents an alkylene group, and B represents an oxygen atom, a sulfur atom, or a group shown by the following formula, wherein R 4 represents an alkyl or aryl group substituted with an aryl, cycloalkyl, or heterocyclic group, and X represents an oxygen atom or a sulfur atom.