The molecule is a disaccharide comprising a D-glycero-alpha-D-talo-oct-2-ulosonyl unit in (2->4) linkage with 3-deoxy-alpha-D-manno-oct-2-ulopyranonosonic acid; it forms part of the core structure of bacterial lipopolysaccharides.
(2R,3S,4S,5R,6R)-2-[(2R,4R,5R,6R)-2-carboxy-6-[(1R)-1,2-dihydroxyethyl]-2,5-dihydroxyoxan-4-yl]oxy-6-[(1R)-1,2-dihydroxyethyl]-3,4,5-trihydroxyoxane-2-carboxylic acid