Abstract
The absolute configuration of (4R)-2-(2-hydroxyphenyl)-3-(3-mercaptopropionyl)-4-thiazolidinecarboxylic acid (11a), SA 446, which has a potent inhibitory activity against angiotensin I-converting enzyme (ACE), was determined to be (2R, 4R) by nuclear magnetic resonance (NMR) spectroscopy, specific rotation measurement and X-ray crystallography. The structure-activity relationships of the (2R, 4R)-and (2S, 4R)-isomers are discussed, and stereoselective acylation of (4R)-2-aryl-4-thiazolidinecarboxylic acids (1-3) is also described.
