Abstract: Hypotensive activity is exhibited by compounds having the formula ##STR1## and pharmaceutically acceptable salts thereof wherein R.sub.1 is hydrogen or alkyl;R.sub.2 and R.sub.3 are each independently phenyl, substituted phenyl, cycloalkyl, or R.sub.2 is hydrogen and R.sub.3 is heteroaryl;R.sub.4 and R.sub.5 are the same or different and each is hydrogen, hydroxy, alkoxy, alkanoyl or alkyl;R.sub.6 is hydrogen or alkyl; andn is 1, 2, 3 or 4; with the proviso that if R.sub.2 and R.sub.3 are each phenyl, at least one of R.sub.1, R.sub.4, R.sub.5 and R.sub.6 is other than hydrogen.

Abstract: A method is provided for making substituted prolines of the structure ##STR1## wherein X is lower alkyl or aryl, R is H, lower alkyl or an alkali metal and Z is an N-protecting group, which method includes the step of reacting a compound of the structure ##STR2## wherein Z and R are as defined above and Q is Br. tosyloxy or mesylate, with an organic copper lithium compound of the structureXYCuLiwherein X is as defined above and Y is lower alkyl, aryl or CN.Where X is phenyl, the corresponding 4-cyclohexyl compound may be produced by conventional hydrogenation techniques.The compounds produced are useful as intermediates in the preparation of phosphinic acid derivatives useful in the treatment of hypertension.