Abstract: A series of(25)N-phenyl piperazine derivatives was screened for tranquillizing and adrenolytic actions. Compound(25), 1-(3,4,5-trimethexy phenethyl)-4-(p-chloro-phenyl) piperazine was found to be the most active. This compound was active in the following tests in addition to preliminary screening: anti-mescaline, anti-amphetamine toxicity in grouped mice, catalepsy and ptosis, hypothermia, potentiation of morphine analgesia, anti-emetic and Rhesus monkey taming. Gompound(25) also showed a pronounced α-adrenoreceptor blocking action and certain cardiovascular effects.