The molecule is a tetrasaccharide consisting of beta-D-Delta(4)-glucopyranuronic acid, beta-D-glucopyranosyl, alpha-L-rhamnopyranosyl and beta-D-glucopyranosyl residues, joined in sequence by (1->4), (1->4) and (1->3)-glycosidic bonds, respectively. It is a conjugate acid of a beta-D-Delta(4)-GlcpA-(1->4)-beta-D-Glcp-(1->4)-alpha-L-Rhap-(1->3)-beta-D-Glcp(1-).
(2R,3R,4S)-2-[(2R,3S,4R,5R,6S)-6-[(2S,3R,4S,5R,6S)-4,5-dihydroxy-2-methyl-6-[(2R,3R,4S,5R,6R)-2,3,5-trihydroxy-6-(hydroxymethyl)oxan-4-yl]oxyoxan-3-yl]oxy-4,5-dihydroxy-2-(hydroxymethyl)oxan-3-yl]oxy-3,4-dihydroxy-3,4-dihydro-2H-pyran-6-carboxylic acid