Benzolactams. A new class of converting enzyme inhibitors

Abstract A series of potent inhibitors of angiotensin-converting enzyme (dipeptidyl carboxy-peptidase, E.C. 3.4.15.1) derived from benzofused 1-carboxyalkyl-3-(1-carboxy-3-phenylpropylamino) lactams ( III ) is described. In the most effective inhibitors (I 50 2-4X10 −9 M) the lactam is 7 or 8 membered and the N-1 side chain is carboxymethyl or carboxyethyl. Conformational and steric factors pertinent to binding to the enzyme are discussed.