The structure of an acidic polysaccharide isolated from Abtorna august
a root bark was determined by sugar and methylation analyses and high
resolution H-1- and C-13-NMR spectroscopy. The main chain of the polys
accharide was composed of 1,2-linked alpha-L-rhamnopyranose and 1,4- o
r 1,3-lifiked alpha-D-galacturonic acid residues. The terminal beta-D-
glucuronic acid residue was attached to the 3- and/or 4-position of th
e alpha-D-galacturonic acid residue.