The molecule is a trisaccharide that is D-galactopyranose in which the hydroxy groups at positons 3 and 4 have been converted into the corresponding beta-D-glucopyranosyl and beta-L-fucopyranosyl derivatives, respectively.
(2R,3S,4R,5S,6S)-2-[(2R,3S,4R,5R)-5,6-dihydroxy-2-(hydroxymethyl)-4-[(2S,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxyoxan-3-yl]oxy-6-methyloxane-3,4,5-triol