Synthesis and anticonvulsant activity of substituted thiourea derivatives

Twelve new thiourea derivatives were prepared by the reacting of 4-aminophenylacetic acide with substituted isothiocyanates. Their chemical structures were proved by means of IR, 1H-NMR, mass spectroscopic and elemental analyses. These compounds were tested at dose of 50 mg/kg for their anticonvulsant activity using by pentylenetetrazole induced seizure (PTZ) and maximal electroshock seizure (MES) tests in mice. Compound 1b, (4-{[(4-chlorophenyl) thiocarbamoyl] amino} phenyl) acetic acid, was found to be more active than the other tested compounds. The compound 1b reduced convulsions in all types of grades (from grade I to V), therefore it increased convulsive threshold. It also increased onset time from 1.20 to 2.58 sec. and survival % from 50 to 95.