Cucurbitacins as Constituents of Wilbrandia ebracteata.

The methanolic extract from the roots of WILBRANDIA EBRACTEATA afforded, in addition to the known dihydrocucurbitacins B and E, dihydroisocucurbitacin B, Cucurbitacins B, D, E, G, H, P, and 22-deoxycucurbi-tacin D, four new compounds whose structures were elucidated as (20 R,24xi)-3)3beta,16alpha,20)24,25-pentahydroxy-10alpha-cucurbit-5-ene-2,11,22-trione (3- EPI-isocucurbitacin G) ( 8), (20 R,22xi)-2beta16a,20,22,25-pentahydroxy-10alpha-cucurbita-5,23 T-diene-3,11-dione ( 13), (20 R)-25-acetoxy-3,16alpha,20-trihydroxy-30- NOR-2-(beta- D-glucopyranosyloxy)-1,2,3,4,5,10-dehydrocucurbit-6-ene-11,22-dione ( 14), and dihydroisocucurbitacin B-3-glucoside ( 16).