A method of reversed-phase high performance liquid chromatography (RP-HPLC) using diode array detection (DAD) was developed for the quantitative determination of 3'-geranyl-5,7,4'-trihydroxyisoflavone (compound 1) and 8,9-dihydroxy-1-methoxy-[6',6'-dimethylpyrano(2',3': 2,3)]pterocarpene (compound