STEROIDAL SAPONINS FROM FRUITS OF TRIBULUS-TERRESTRIS

Further studies on the constituents of the fruits of Tribulus terrestr is led to the isolation of six new furostanol saponins, 26-O-beta-D-gl ucopyranosyl (25R)-furostane-2 alpha,3 beta,22 alpha,26-tetrol-3-O-bet a-D-glucopyranosyl (1-4)-beta-D-galactopyranoside, 26-O-beta-D-glucopy ranosyl (25R, S)-5 alpha-furostane-2 alpha,3 beta,22 alpha, 26-tetrol- 3-O-<bane-2 alpha eta>-D-galactopyranosyl ta-D-glucopyranosyl(1-4)-bet a-D-galactopyranoside, 26-O-beta-D-glucopyranosyl (25R,S)-5 alpha-furo stane-3 beta,22 alpha, 26-triol-3-O-beta-3 beta D-galactopyranosyl(1-2 )-beta-D-glucopyranosyl (1-4)-beta-D-galactopyranoside, 26-O-beta-D-gl ucopyranosyl (25R, S)-5 alpha-furostan-12-one-3 beta,22 ta-D-glucopyra nosyl(1-4)-beta-D-galactopyranoside, 26-O-beta-D-glucopyranosyl (25R, S)-furost-5-ene-3 beta,22 alpha,26-triol-3-O-beta-D-galactopyranosyl ( 1-2)-beta-D-glucopyranosyl (1-4)-beta-D-galactopyranoside, 26-O-beta-D -glucopyranosyl (25R)-5 alpha-furost-20(22)-en-12-one-3 beta, 26-diol- 3-O-beta-D-galactopyranosyl (1-2)-beta-D-glucopyranosyl (1-4)-beta-D-g alactopyranoside, named terrestrosin F-K, respectively. The structures were elucidated on the basis of spectroscopic studies of the isolated compounds and their hydrolysed products. (C) 1997 Published by Elsevi er Science Ltd.