Piperazine derivatives of formula I ##STR1## and their pharmaceutically acceptable acid addition salts are 5-HT.sub.1A binding agents, particularly 5-HT.sub.1A antagonists and may be used, for example, as anxiolytics. In the formula R is hydrogen or one or two lower alkyl groups, R.sup.1 is a mono of bicyclic aryl or heteroaryl radical, R.sup.2 is aryl and A is a C.sub.2-5 alkylene chain optionally substituted by lower alkyl.
式I中的
哌嗪衍
生物##STR1##及其药学上可接受的酸加盐是5-HT.sub.1A结合剂,特别是5-HT.sub.1A拮抗剂,例如可用作
抗焦虑药物。在公式中,R是氢或一个或两个较低的烷基,R.sup.1是单个或双环芳基或杂环芳基基团,R.sup.2是芳基,A是C.sub.2-5的烷基链,可选地被较低的烷基取代。