New triterpenoidal saponins acylated with monoterpenic acid from Albizia adianthifolia

Four new triterpenoidal saponins acylated with monoterpenic acid, i.e., adianthifoliosides C. D, E, and F (1-4), besides the two known julibroside III and the monodesmonoterpenyl elliptoside A, were isolated from the roots of Albizia adianthifolia. Their structures were elucidated on the basis of extensive 1D- and 2D-NMR studies and mass spectrometry as 3-O-(O-alpha-L-arabmopyranosyl-(1 --> 2)-O-beta-D-fucopyranosyl-(I --> 6)-O-beta-D-glucopyranosyl-(1 --> 2)]-beta-D-glucopyranosyl}-21-O-{(2E,6S)-6-({4-O-[(2E,6S)-2,6-dimethyl-6-(beta-D-quinovopyranosyloxy)octa-2,7-dienoyl]-beta-D-quinovopyranosyl)oxy)-2-(hydroxymethyl)-6-methylocta-2,7-dienoyllaca-cic acid 28-[O-alpha-L-arabinofuranosyl-(1 -->4)-O-[beta-D-glucopyranosyl-(I --> 3)]-O-alpha-L-rhamnopyranosyl-(1 --> 2)[3-D-glucopyranosyll ester (1), 21-O-1(2E,6S)-6-[{4-O-[(2E,6S)-2,6-dimethyl-6-beta-D-quinovopyranosyloxy)octa-2,7-dienoyl]-beta-D-quinovopyranosylloxy)-2-(hydroxymethyl)-6-methylocta-2,7-dienoyl}-3-O-[O-beta-D-xylopyranosyl-(l - 2)-0-fi-D-fucopyranosyl-(I --> 6)-2-(acetylamino)-2-deOXy-p-D-glucopyranosyllacacic acid 28-[O-aL-arabinofuranosyl-(l --> 4-O-[beta-D-glucopyranosyl-(1 --> 3)-O-alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-glucopyranosyl) ester (2), 21-O-[(2E,6S)-6-({3-O-[(2E,6S)-2,6-dimethyl-6-(beta-D-quinovopyranosyloxy)octa-2,7-dienoyl]-beta-D-quinovopyranosylloxyl-2.6-dimethyloctit-2,7-dienoyl]-beta-D-quinovopyranosyl}(I oxy}2}-O-P-D-fucopyranosyl-(1 --> 6)-2-(acetylamino)-2-deoxy-beta-D-glucopyranosyl}acacic acid 28-{O-alpha-L-aribinofuranosyl-(I --> 4)-O-[beta-D-glucopyranosyl-(l --> 3)]-O-alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-glucopyranosyl} ester (3), and 3-O-[O-alpha-L-arabinopyranosyl-(1 --> 2)-O-beta-D-fucopyranosyl-(I --> 6)-O-[beta-D-glucopyranosyl-(I --> 2)]-beta-D-glucopyranosyl)21-O-[(2E,6S)-2,6-dimethyl-6-( beta-D-quinovopyranosyloxy)octa-2,7-dienoyl)acacic acid 28-[O-alpha-L-arabinofuranosyl-(l --> 4)-O-[beta-D-glucopyranosyl-(I --> 3)]-O-alpha-L-rhamnopyranosyl-(I --> 2)-beta-D-glucopyranosyl) ester (4).