Schoeprin A, B, C:: three new chalcone C-glycosides from Schoepfia chinensis

Three new chalcone C-glycosides named schoepfin A, B, C (1-3), together with three known compounds 4,2 ',4 '-trihydroxy-3 '-C-beta-D-glucosylchalcone (4), nothofagin (5) and hemiphloin (6) were isolated from ethanolic extract of the bark of Schoepfia chinensis Gardn. et Champ (Olacaceae). Their structures were determined mainly by spectroscopic techniques including 2D-NMR (HMBC, HMQC) and MS experiments.