The molecule is a trisaccharide consisting of alpha-L-arabinofuranose and alpha-L-arabinopyranose residues joined in sequence by a (1->2) glycosidic bond, and in which a beta-D-glucopyranose residue has been attached to the arabinopyranose residue by a (1->3) glycosidic bond. It derives from a 3-O-beta-D-Glcp-(1->3)-alpha-L-Arap.
(2S,3R,4S,5S,6R)-2-[(2R,3R,4S,5S)-3-[(2S,3R,4R,5S)-3,4-dihydroxy-5-(hydroxymethyl)oxolan-2-yl]oxy-2,5-dihydroxyoxan-4-yl]oxy-6-(hydroxymethyl)oxane-3,4,5-triol