Design & synthesis of N'-[substituted] pyridine-4-carbohydrazides as potential anticonvulsant agents.

A series of N'-[substituted] pyridine-4-carbohydrazides were designed and synthesized keeping in view the structural requirement of pharmacophore and evaluated for anticonvulsant activity and neurotoxicity. The anticonvulsant activity of the titled compounds was established after intraperitoneal administration in three seizure models, which include MES, scMET and 6 Hz model. The most active compound of the series was N'-[4-(4-fluorophenoxy)benzylidene]pyridine-4-carbohydrazide PCH 6, which showed a MES ED50 value of 128.3 mg/kg and 6 Hz ED50 value of 53.3 mg/kg in mice. The median toxic dose (TD50) was 343.6 mg/kg, providing compound PCH 6 with a protection index of 2.67 in the MES test and 6.44 in 6 Hz test. A computational study was also carried out, including calculation of pharmacophore pattern, prediction of pharmacokinetic properties and docking studies.