Thiolactam-n-acetic acid derivatives, their production and use

Abstract From the Canadian patent

Compounds of the general formula: (wherein, R1 and R2 are, the same or different hydrogen, a halogen, a lower alkyl, a cycloalkyl a, lower alkoxy, a phenylalkyloxy, or trifluoromethyl; R3 is hydrogen or methyl; R4 is carboxyl or an esterified carboxyl; and X is oxygen or sulfur) or a salt thereof, are novel compounds possess, aldose reductase inhibitory and platelet aggregation inhibitory activities, and of use as drugs for prevention and treatment of diabetic complications such as diabetic cataract, retinopathy, nephropathy and, neuropathy.