Synthesis and anticonvulsant activity of 4-oxo and 4-thioxo-8-bromobenzopyran derivatives.

Several thiosemicarbazones (7 and 8), 1,3-thiazolidin-4-ones (9, 10, 13, 14) and 2-thioxo-1,3-imidazolidin-4-ones (11) have been prepared starting from 8-bromo-7-hydroxy-5-methoxy-2-methyl-4-oxo-4H-1-benzopyran-6-carbaldehyde (3) and its 4-thio analogue (4). The anticonvulsant activity of all of the synthesized compounds was evaluated against maximal electrical shock (MES) and subcutaneous pentylenetetrazole (scPTZ) induced seizures. The neurotoxicity was assessed using the rota-rod test. Some of the tested compounds displayed potent anticonvulsant activity in the scPTZ test.