New isoflavones and flavanol from Iris potaninii.

Two new isoflavones, 6, 3', 4'-trimethoxy-7, 8, 5'-trihydroxyisoflavone (1), 7, 4'-dimethoxy-8, 3', 5'-trihydroxy-6-O-beta-D-glucopyranosylisoflavone (2), and 5, 3, 3'-trihydroxy-7, 4'-dimethoxyflavanone (3) have been isolated from the underground parts of Iris potaninii along with known isoflavones (4-8) and iriflophenone (9). The structures of the new compounds were determined using NMR and mass spectroscopic methods.