Synthesis and Anticonvulsant Activity Evaluation of 6-phenyl-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazines

Various 6-phenyl-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazine derivatives (3a-3n) were designed keeping in view the wide bioactivities of 1,2,4-triazoles and their fused heterocyclic derivatives. All target compounds 3a-3n, characterized by IR, 1H-NMR and MS, have been evaluated for their anticonvulsant activity against MES-induced seizures. The pharmacological results showed that most of the compounds displayed some degree of anticonvulsant activity. Among them, 6-(4-chlorophenyl)-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazine (3h) was the most promising compound with an ED50 value of 40.9 mg/kg and a PI value of 6.5.