COMPARATIVE CENTRAL DEPRESSANT ACTIONS OF SOME 5-PHENYL-5-ALKENYL BARBITURIC ACIDS

The maximum anticonvulsant activity within the series of 5-phenyl-5-alkyl barbituric acids was found to be exhibited by the butyl derivative in the study of Alles, Effis, Feigen and Redemann (1). This phenyl butyl barbituric acid exerted markedly less hypnotic action than related derivatives having more moderate anticonvulsive effectiveness. However, it now appears that the low solubiity in water of the free phenyl butyl barbituric acid makes oral administra-tion of this compound, even in the form of its sodium salt, only partially effective as compared with its effectiveness when injected intraperitoneally as a solution of the sodium salt. After oral administration of the sodium salt into the stomach a considerable amount of the salt is converted into the relatively insoluble free acid from reaction with the resting hydrochloric acid of the stomach or neutral buffering systems of the tissues of the gastrointestinal tract. To search for compounds that might have greater water solubiity, yet share with phenyl butyl barbituric acid its relatively high anticonvulsive effectiveness, study was extended to the phenyl unsaturated-alkyl barbituric acids. To valu