Dipeptide mimics. Conformationally restricted inhibitors of angiotensin-converting enzyme

A series of potent inhibitors of angiotensin-converting enzyme (dipeptidyl carboxy-peptidase, E.C. 3.4.15.1) is described which addresses conformational aspects of the enzyme-inhibitor interaction. Conformational probes were derived from simple lactams containing the required recognition and binding elements. The inhibitor potencies vary with lactam ring size in a manner predicted from molecular modeling studies and help map the active site of this important enzyme.