Evaluation of anticonvulsant activities of bis(3-aryl-3-oxo-propyl) ethylamine hydrochlorides and 4-aryl-3-arylcarbonyl-1-ethyl-4-piperidinol hydrochlorides.

Bis-Mannich bases, bis(3-aryl-3-oxopropyl)ethylamine hydrochlorides 1-4, and their corresponding structural and non-classical isomers, 4-aryl-3-arylcarbonyl-1-ethyl-4-piperidinol hydrochlorides 5-8, were synthesized. The aryl part was phenyl in 1 and 5, p-methylphenyl in 2 and 6, p-chlorophenyl in 3 and 7, and 2-thienyl in 4 and 8. The chemical stuructures of the compounds were confirmed by 1H-NMR, 13C-NMR, UV, IR and elemental analyses. Anticonvulsant activities of the compounds were evaluated by the maximum electroshock (MES) and subcutaneous pentylenetetrazole (scMet) tests in the dose range of 30-300 mg/kg. Alterations in biological activity depending on modifications in chemical structure were also followed. Compounds 1-4, 6, and 8 were toxic and caused death of the animals 20 min after the injection. Compounds 2, 3 and 6 were also neurotoxic at the 100 mg/kg dose level. While only compound 7 was active in the scMet test at 300 mg/kg within 4 h, all the compounds showed activity in the MES test at different dose levels and time periods. In conclusion, compounds 5 and 7, which were not toxic and did not show neurotoxicity, seemed to be candidate compounds to develop new anticonvulsant compounds useful in the treatment of the grand mal (compounds 5, 7) and petit mal (compound 7) epilepsies.