Stereochemistry of isoflavone reduction during the biosynthesis of (+)-and (–)-pterocarpans: 2H n.m.r. studies on the biosynthesis of (+)-pisatin and (–)-medicarpin
Abstract
2 H N.m.r. Spectroscopy has indicated the overall Z addition of hydrogen to the double bond of formononetin (3) during the bisosynthesis of (+)-(6aR, 11aR)-pisatin (6), in contrast with an E addition during production of (–)-(6aR, 11aR)-medicarpin (1).