Synthesis of cholestane glycosides bearing OSW-1 disaccharide or its 1-->4-linked analogue and their antitumor activities.

For further structure-activity relationship (SAR) research of OSW saponins, a cholestane glycoside, namely 3beta, 16beta, 26-trihydroxycholest-5-en-22-one 16-O-(2-O-4-methoxybenzoyl-beta-D-xylopyranosyl)-(1-->3)-2-O-acetyl-alpha-L-arabinopyranoside (1) together with two 1-->4-linked disaccharide analogues (2 and 3) were synthesized. Their cytotoxic activities were evaluated by the standard MTT assay. Compound 1 showed potent cytotoxicity against five types of human tumor cells, with IC50 ranging between 1.3 and 73 nM. Copyright (c) 2010 Elsevier Ltd. All rights reserved.