Synthesis and Biological Activities of 8'-Methylene- and 8'-Methylidyneabscisic Acids

Abstract

8'-Methylene- and 8'-methylidyneabscisic acids which might act as suicide inhibitors of the 8'-hydroxylase of abscisic acid, were designed, synthesized, and optically resolved. The (+)-isomers showed stronger inhibitory activity in rice elongation and in lettuce seed germination than (+)-abscisic acid. The activity of (+)-8'-methylidyneabscisic acid was the strongest of the analogues synthesized to date, 40-fold stronger than abscisic acid.