Isoflavones from stems of Euchresta horsfieldii

Abstract Four new prenyl(=3-methyl-2-butenyl)isoflavones, euchrenones b 6 -b 9 , were isolated from stems of Euchresta horsfieldii from Thailand in addition to four known isoflavones (warangalone, osajin, 6,8-di(3-methyl-2-butenyl)genistein and 8- O -methylretusin) and two pterocarpans (maackiain and sophoracarpan B). 1 H NMR spectral properties of regio-isomers, such as warangalone and osajin, are also discussed.