[Development of new antiepileptics. II. Anticonvulsant effect of hydantoin derivatives].

From a series of N-substituted hydantoin derivatives, 1-phenyl-3-(o-chloro-p-sulfonamide-phenyl)-hydantoin was found to exhibit the best anticonvulsant activity against electroshock seizures. This substance showed also a weak activity against pentylenetetrazole seizures, as well as minor analgesic and sedative effects. The toxic effects are negligible; the lethal dose in mice was higher than 5000 mg/kg p.o. The other tested hydantoin derivatives showed much weaker anticonvulsant activities.