ANTICONVULSANT AND CONVULSANT EFFECTS OF CHEMICALLY RELATED THIOSEMICARBAZIDE. THIOUREA AND UREA DERIVATIVES

¹ Baxter Laboratories, Inc., Morton Grove, Illinois

Eleven thiourea derivatives and their corresponding urea and thiosemicarbazide (TSC) analogues were tested for anticonvulsant properties. Compounds which had o-chlorobenzyl or o-methylbenzyl substitutions on one of the nitrogens had the greatest anticonvulsantpotency. The TSC derivatives may be divided into three groups, according to the relationship of activity and structure, as follows: 1) convulsant, with alkyl or allyl substitutions;2) anticonvulsant against maximal electroshock seizures, with substituted phenyl or benzyl groups; and 3) both anticonvulsant and convulsant, with simple or substituted phenyl or benzyl groups. None of the TSC derivatives was anticonvulsant against Metrazol, and all tended to exacerbate this clonic seizure pattern. The convulsions produced by TSC derivatives could be abolished or prevented by pyridoxal HCl. All TSC derivatives with antimaximal electroshock seizure activity, including those which also induced delayedseizures, caused a reduction in spontaneous motor activity.