Prenylisoflavone derivatives from the roots of Hedysarum scoparium

Four new prenylisoflavone derivatives, namely, 5-hydroxy-4 '-methoxy-8-prenyl-2 ''-hydroxyisopropyldihydrofurano[4,5:6,7]-isoflavone(1), 5-hydroxy-4 '-methoxy-6-prenvi-2 '''-hydroxyisopropyldihydrofurano[4,5:8,7]isoflavone (2), 5-hydroxy-4 '-methoxy-8-prenyl-1 '',2 ''-peroxyl-3 '',3 ''-dimethyldihydropyrano[5,6:6,7]-isoflavone (3), and 5-hydroxy-4 '-methoxy-6-prenyl-1 ''',2 '''-peroxyl-3 ''',3 '''-dimethyldihydropyrano[5,6:8,7]-isoflavone (4), together with three known ones 5-7, were isolated from the roots of Hedysarum scoparium. Their structures were established by means of detailed spectroscopic analysis (111, EI- or HR-ESI-MS as well as 1D- and 2D-NMR), and by comparison of their spectroscopic data with those reported for structurally related compounds.