The molecule is a trisaccharide that is lactose in which the hydroxy group at the 3' position has been converted to the corresponding D-galactopyranosyl derivative. It is a trisaccharide and a partially-defined glycan. It derives from a lactose and a D-galactopyranose.
(3R,4S,5R,6R)-2-[(2R,3S,4S,5R,6S)-3,5-dihydroxy-2-(hydroxymethyl)-6-[(2R,3S,4R,5R)-4,5,6-trihydroxy-2-(hydroxymethyl)oxan-3-yl]oxyoxan-4-yl]oxy-6-(hydroxymethyl)oxane-3,4,5-triol