Design, synthesis and anticonvulsant activity evaluation of 7-substituted-4H-[1,2,4]triazino[3,4-a]phthalazin-4-one derivatives

in this study, a novel series of 7-substituted-4h-[1,2,4]triazino[3,4-a]phthalazin-4-one derivatives was synthesized as potential anticonvulsant agents. their anticonvulsant activities were evaluated by the maximal electroshock (mes) test, and their neurotoxicities were evaluated by the rotarod neurotoxicity test. the pharmacological results showed that 7-hexyloxy-4h-[1,2,4]triazino[3,4-a]phthalazin-4-one 4e was the most potent with median effective dose (ed50) value of 6.6 mg kg-1, median toxicity dose (td50) of 39.4 mg kg-1, providing a protective index (pi=td50 /ed50) value of 6.0.