Two new prosapogenins from Albizia adianthifolia

Two new triterpenoidal prosapogenins 1 and 2 were obtained from the mild alkaline hydrolysate of the crude saponin fraction of Albizia adianthifolia (Mimosaceae) roots. Their structures were mainly determined by spectral analyses as acacic acid 3-O-beta-D-xylopyranosyl-(1-->2)-beta-D-fucopyranosyl-(1-->6)- 2-acetylamino-2-deoxy-beta-D-glucopyranoside (1) and acacic acid 3-O-(beta-D-xylopyranosyl-(1-->2)-beta-D-fucopyranosyl-(1-->6)- [beta-D-glucopyranosyl-(1-->2)]-beta-D-glucopyranosyl)-21-O-(6(S)-2- hydroxymethyl-6-methyl-6-O-(beta-D-quinovopyranosyl)-2,7-octadienoyl) ester (2). Furthermore, the known julibroside A3 was isolated from the crude saponin mixture. Compounds 1 and 2 did not show any ability to potentiate in vitro cisplatin cytotoxicity in a human colon cancer cell line.