ANALOGIFREMGANGSMAADE TIL FREMSTILLING AF HALOGENSUBSTITUEREDE BENZOPYRAN- ELLER BENZOTHIOPYRAN-4-CARBOXYLSYRE-FORBINDELSER ELLER C1-4ALKYLESTERE DERAF ELLER FARMACEUTISK ACCEPTABLE SALTE DERAF MED BASER

摘要

Benzopyran- and benzothiopyran-4 -carboxylic acid aldose reductase inhibitors of the formula: …… or a pharmaceutically acceptable salt thereof, wherein x is 0, S, S = O or …… n is zero or one; R is hydrogen or alkyl of 1 to 4 carbon atoms; R1 is hydrogen, chloro, bromo, fluoro or phenyl; R2 and R3 when taken individually, are each hydrogen, alkyl of 1 to 3 carbon atoms, chloro, bromo or fluoro; and when taken together, R2, R3 and the carbon atoms to which they are connected form a fused benzene ring; with the proviso that at least one of R1, R2 and R3 is chloro, bromo or fluoro. The compounds are useful in the treatment of diabetic-associated complications, such as cataracts, neuropathy or retinopathy, in a diabetic host. Also disclosed are methods for preparing the compounds of the formula (I) and their salts, and pharmaceutical compositions containing them.