Plant gums of the Genus Sterculia. Part IV. Acidic oligosaccharides from Sterculia urens gum

Abstract

The acidic oligosaccharides formed on partial depolymerisation of Sterculia urens gum have been further examined. Previously uncharacterised oligosaccharides include 4-O-(α-D-galactopyranosyluronic acid)-D-galactose, O-(galactopyranosyluronic acid)-(1 → 2)-O-rhamnopyranosyl-(1→ 4)-galactose, O-(galactopyranosyluronic acid)-(1 → 2)-O-rhamnopyranosyl-(1 → 4)-galacturonic acid, and 3-O-(glucopyranosyluronic acid)-galacturonic acid from partial acid hydrolysis, and O-galactopyranosyl-(1 → 2)-O-(galactopyranosyluronic acid)-(1 → 4)-galactose from partial acetolysis. The configuration of the glycosidic linkage in 2-O-(α-D-galactopyranosyluronic acid)-L-rhamnose has been confirmed by degradation to 2-O-α-D-galactopyranosylglycerol.