The molecule is a linear tetrasaccharide comprising three L-glycero-alpha-D-manno-heptose residues and a 3-deoxy-alpha-D-manno-oct-2-ulosonic acid (2-keto-3-deoxy-alpha-D-mannooctanoic acid, alpha-Kdo) residue in a (1->7), (1->3), (1->5) sequence.
(2R,4R,5R,6R)-6-[(1R)-1,2-dihydroxyethyl]-5-[(2R,3S,4S,5R,6R)-6-[(1S)-1,2-dihydroxyethyl]-4-[(2R,3S,4S,5S,6R)-6-[(1S)-2-[(2S,3S,4S,5S,6R)-6-[(1S)-1,2-dihydroxyethyl]-3,4,5-trihydroxyoxan-2-yl]oxy-1-hydroxyethyl]-3,4,5-trihydroxyoxan-2-yl]oxy-3,5-dihydroxyoxan-2-yl]oxy-2,4-dihydroxyoxane-2-carboxylic acid