Synthesis and Evaluation of Anticonvulsant Activities of Pyrazol yl Semicarbazones. Part II

A series of 2-((5-aryloxy-1-methyl-3-methyl-1H-pyrazol-4-yl)methylene) hydrazinecarboxamides (6a-6l) and 2-((5-aryloxy-1-methyl-3-phenyl-1H-pyrazol-4-yl)methylene) hydrazinecarboxamides (7a-7l) were designed and synthesized. The maximal electroshock shock (MES) and subcutaneous pentylenetetrazole (sc-PTZ) seizure models in mice were used to evaluate the antiepileptic effect of compounds synthesized. Further, the acute neurotoxicity profile was also studied via the rotarod test. The results of sc-PTZ test indicate that a majority of compounds possessed anticonvulsant activity with long duration of protection effects. Among of them, compound 6k was found to be the most promising one, with an ED50 value of 20.4 mg/kg (in sc-PTZ model) and a PI value of 10.8, possessing higher anti-PTZ activity and wider safety margin than valproate and ethosuximide.