Methods for preparing anti-hypertensive agents.

A plurality of methods are disclosed for preparing compounds having the formula: <CHEM> wherein R is hydrogen, formyl, acetyl, propanoyl, butanoyl, phenylacetyl, phenylpropanoyl, benzoyl, cyclopentanecarbonyl, tert-butyloxycarbonyl, cyclopentanecarbonyl-L-lysyl, pyro-L-glutamyl-L-lysyl, L-lysyl, L-arginyl or pyro-L-glutamyl; A is phenylalanyl, alanyl, tryptophyl, tryptophyl, tyrosyl, glycyl isoleucyl, leucyl, histidyl, or valyl, the alpha -amino group thereof being in amide linkage with R; R1 is hydrogen or methyl, R2 is L-proline, L-3,4-dehydroproline, D,L-3,4-dehydroproline, L-3-hydroxyproline, L-4-hydroxyproline, L-thiazolidine-4-carboxylic acid, or L-5-oxo-proline, the imino group thereof being in imide linkage with the adjacent - @-; and, n is 0 or 1, such that when n is 0, R1 is methyl, and where n=1, and R1 is methyl the -CH2-@@3- moiety is in the D-configuration. These compounds are inhibitors of angiotensin converting enzyme.