Studies on chemical constituents of flavonids in Hypericum attenuatun

OBJECTIVE: To study the chemical constituents of flavonids in Hypericum attenuatum Chois. METHODS: Various chromatographic techniques were used to separate and purify the constituents. The spectral data(MS and NMR) were obtained for structure elucidation. RESULTS: Eleven compounds of flavonids were elucidated as 5,7,3′,4′-tetrahydroxyflavanol(I), kaempferol(II), C-3/C-8″ biapigenin(III), quercetin(IV), quercetin-3′-O-β-D- glucoside(V), quercetin-3′-O-L-rhamnoside(VI), hyperin(VII), 5,7,3′,4′-tetrahydroxy-dihydroflavanol-3-O-L-rhamnoside(VIII), quercetin-4′-O-β-D-glucoside(IX), isoquerecitrin(X), querecitrin(XI). CONCLUSION: Flavonids are the main chemical constituents of Hypericum attenuatum Chois. Compounds I, III, V, VI, VIII and IX are isolated from this plant for the first time.