Flavones and isoflavones from the west African Fabaceae Erythrina vogelii.
The CH(2)Cl(2)/MeOH extract of the stem bark of Erythrina vogelii (Fabaceae) from Nigeria has yielded two novel isoflavones, 7,4'-dihydroxy-8-(gamma,gamma-dimethylallyl)-2''zeta-(4''-hydroxyisopropyl)dihydrofurano[1'',3'':5,6]isoflavone (vogelin H) (1) and 7,4'-dihydroxy-8-[(2'''zeta,3'''-dihydroxy-3'''-methyl)butyl]-2'',2''-dimethyl-3'',4''-dehydropyrano[1'',4'':5,6]isoflavone (vogelin I) (2), a novel flavone, 7,4'-dihydroxy-2'',2''-dimethyl-3'',4''-dehydropyrano[1'',4'':5,6]flavone (vogelin J) (3), and eight known flavonoids.