A new class of angiotensin-converting enzyme inhibitors.

Much current attention focuses on the renin-angiotensin system in relation to mechanisms controlling blood pressure and renal function. Recent demonstrations (ref. 1, ref. 2 and refs therein) that angiotensin-converting enzyme inhibitors show promising clinical antihypertensive properties have been of particular interest. We now report on the design of a novel series of substituted N-carboxymethyl-dipeptides which are active in inhibiting angiotensin-converting enzyme at nanomolar levels. We suggest that these compounds are transition-state inhibitors and that extensions of this design to other metalloendopeptidases merit further study.

Structural requirements for the binding of prostaglandins.

The binding of prostaglandins and analogs to the lipocyte PGE receptor was shown to exhibit a high degree of structural specificity. Small changes, particulary at the 9-keto or 15-hydroxyl position, were found to drastically diminish interaction with the receptor. Studies of a rather substantial number of compounds revealed a close relationshio between affinity for the lipocyte PGE receptor and the ability to stimulate cyclic AMP synthesis in the isolated mouse ovary. In general, activities in these two parameters follow the biological potencies generally recognized for the compounds.