Renin inhibitors. Design of angiotensinogen transition-state analogs containing novel (2R,3R,4R,5S)-5-amino-3,4-dihydroxy-2-isopropyl-7-methyloctanoic acid

Abstract

A highly stereoselective synthesis of 2(R)-[5(R)-[1(S)-[(tert-butyloxycarbonyl)amino]-3-methylbutyl]2,2-dimethyl-4(R)-dioxolanyl]-3-methylbutanoic acid (11) is described. This is a suitably protected carboxylic acid useful as an intermediate for the preparation of renin inhibitory peptides. Angiotensinogen analogues such as peptides IX and X that contain the dipeptide isostere (2R,3R,4R,5S)-5-amino-3,4-dihydroxy-2-isopropyl-7-methyloctanoic acid residue at the scissile site are shown to be potent inhibitors of human plasma renin. The glycol moiety in this novel acid, dihydroxyethylene isostere, is suggested to act as a transition-state analogue and mimics the tetrahedral intermediate formed during the enzyme-catalyzed hydrolysis of the peptidic bond.