Baclofen (8-@-chloropheny1)-GABA) is a selective agonist for the bicuculline-insensitive GABAB receptor. The search for new compounds that bind to the GABAB receptor is very important to clarify structural requirements. We report herein the synthesis and the binding studies of variously substituted 3-thienyl-and 3-furylaminobutyric acids. 4Amino-3-(5-methyl- 2-thienyl) butyric acid (6d) and 4-amino-3-(5-chloro-2-thienyl) buty~ ic acid (5h) are potent ...
