Two new flavones from Fordia cauliflora of Yunnan

AimTo study the chemical constituents of the stem of Fordia cauliflora of Yunnan province. MethodsThe constituents were separated and purified by repeated silica column chromatography. The structures were elucidated by physical-chemical properties and spectroscopic data. ResultsSix compounds were isolated from the ethanol extract of the stem of Fordia cauliflora. They were identified as: 6-hydroxy-3-methoxy-6″,6″-dimethylchromeno-(2″,3″∶7,8)-flavone (1), 3-methoxy-6-(3-methyl-but-2-enyloxy)-6″,6″-dimethylchromeno-(2″,3″∶7, 8)-flavone (2), 3,6-dimethoxy-6″,6″-dimethylchromeno-(2″,3″∶7,8)-flavone (3), 7-hydroxy-4′-methoxyisoflavone (4), 7,4′-dihydroxyisoflavone (5) and karanjin (6). ConclusionCompounds 1 and 2 are new compounds. Compounds 3-5 were isolated from the plant for the first time.