Studies On The Constituents of Luffa Acutangula roxb: I: Structures of Acutosides A—G, Oleanane-type Triterpene Saponins Isolated From The Herb

Abstract

From the herb of Luffa acutangula roxb. (Cucurbitaceae), seven oleanane-type triterpene saponins, acutosides A—G, were isolated and their structures were determined. Acutoside A is oleanolic acid 3-O-βto>;glucopyranosyl-(l->;2)-/J-D-glucopyranoside. Acutosides B, D, E, F and G have a common prosapogenin structure, acutoside A, and only differ in the structures of the ester-linked sugar moieties. Acutoside B is a 28-G-[O-β-D-xylopyranosyl-(l->;4)-0-a-L-rhamnopyranosyI-(l→2)-a-L-arabinopyranosyl] ester, D is a 28-0-[O-βl-D-xylopyranosyl-(l→3)-O-βto>;xyIopyranosy l-(1→4)-0-a-L-rhamnopyranosyl-(l 2)-a-L-arabinopyrano-syl] ester, E is a 28-0-[0-a-L-arabinopyranosyl-(l -»3)-O-β-i>;xylopyranosyl-(l→4)-0-a-L-rhamnopyranosyl-{l -°2)-a-L-arabinopyranosyl] ester, F is a 28-0-[O-βl-D-xylopyranosyl-(l->;3)-[O-βl-D-xylopyranosyl-(l->;4)]-0-;3)-O-β-i>;-xylopyranosyl-(l-+4)]-0-;2)-