A Novel Flavonoid from Sophora flavescens

A new dihydroflavonol named kosamol A (1) has been isolated from the roots of Sophora flavescens (Leguminosae) along with twelve related flavonoids. The structure of 1 was determined to be (2R,3R)-5,7,2',4'-tetrahydroxy-6-(3-hydroxy-3-methylbutyl)-8-lavandulylflavanonol on the basis of spectral analyses.