abstract |
A heterocyclic oxophthalazinyl acetic acid having aldose reductase inhibitory activity has the formulan wherein X is oxygen or sulfur, Z is a covalent bond, O, S, NH or CH₂; R₁ is hydroxy, or a prodrug group; R₂ is a heterocyclic group, R₃ and R₄ are hydrogen or the same or a different substituent, and R₅ is hydrogen or methyl. The pharmaceutically acceptable acid addition salts of the above compounds wherein R₁ is di(C₁-C₄)alkylamino or (C₁-C₄)alkoxy substituted by N-morpholino or di(C₁-C₄)alkylamino and the pharmaceutically active base addition salts of the above compounds wherein R₁ is hydroxy are also aldose reductase inhibitors. |