Chemical constituents of Tripterygium wilfordii

The two new triterpenoids, (5 beta ,8 alpha ,9 beta ,10 alpha ,13 beta ,14 beta)-5,9,13-trimethyl-4-oxo-3,24.25,26-tetranor-2,3-secooleanane-2,29-dioi c acid (=4-oxo-D:A-friedo-3-nor-2,3-secooleanane-2,29-dioc acid; 1) and (2 alpha ,3 beta ,4 beta ,5 beta ,8 alpha ,9 beta ,10 alpha ,13 alpha ,14 beta ,24R)-3,24-epoxy-24-ethoxy-2-hydroxy-5,9,13-trimethyl-24,25,26-trinorolean an-29-oic acid (=3 beta ,24-epoxy-24 alpha -ethoxy-2 alpha -hydroxy-D:A-fri edooleanan-29-oic acid; 2) (absolute configurations tentative), together wi th a novel bi-2H-benzopyran, namely (rel-(3R,3'S,4R,4'S)-3,3',4,4'-tetrahyd ro-6,6'-dimethoxy[3,3'-bi-2H-benzopyran]-4,4'-diol (3),were isolated from T ripterygium wilfordii HOOK. F. Their structures were established by chemica l and spectroscopic studies and by X-ray crystallography.