A new O-prenylated flavonol from the roots of Sophora interrupta.

A new O-prenylated flavonol, 3′,4′-dimethoxy-7-(γ,γ-dimethylallyloxy)flavonol (1), together with three known compounds, 2′-hydroxy-3,4-dimethoxychalcone (2), biochanin A (3) and kaempferol-3-O-β-d-glucopyranoside (4), were isolated from the roots of Sophora interrupta Bedd. The structure of compound 1 was elucidated by extensive 1D and 2D NMR spectral studies.