The molecule is a trisaccharide consisting of beta-L-fucopyranose and D-glucopyranose residues joined in sequence by a (1->2) glycosidic bond, in which the hydroxy group at position 3 of the glucopyranose moiety has been glycosylated by beta-D-galactopyranose.
(2R,3S,4R,5S,6S)-2-[(3R,4S,5R,6R)-2,5-dihydroxy-6-(hydroxymethyl)-4-[(2S,3R,4S,5R,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxyoxan-3-yl]oxy-6-methyloxane-3,4,5-triol