Studies on chemical constituents of Hypericum japonicum

OBJECTIVE To investigate the chemical constituents of Hypericum japonicum.METHODS The compounds were separated by chromatography and their chemical structures were elucidated by means of MS,1H-NMR and 13C-NMR spectral methods,respectively.RESULTS Twelve compounds were isolated from the plant,they were identified as isojacareubin(Ⅰ),quercetin(Ⅱ),kaempferol(Ⅲ),quercetin-7-Oα-L-rhamnoside(Ⅳ),quercitrin(quercetin-3-O-α-L-rhamnoside,Ⅴ),isoquercitrin(quercetin-3-O-β-D-glucoside,Ⅵ),miguelianin(quercetin-3-O-β-D-glucuronide,Ⅶ),bijaponicaxanthone(Ⅷ),3,8″-biapigenin(Ⅸ),betulinic acid(Ⅹ),stigmasterol(Ⅺ) and stigmasterol-3-O-β-D-glucopyranoiside(Ⅻ).CONCLUSION Compound Ⅶ,Ⅸ and Ⅻ are isolated from this plant for the first time.