The molecule is the carbohydrate acid derivative anion formed by proton loss from the free carboxy group of alpha-Kdo1Me-(2->8)-alpha-Kdo-OAll It is a conjugate base of an alpha-Kdo1Me-(2->8)-alpha-Kdo-OAll.
(2R,4R,5R,6R)-6-[(1R)-2-[(2R,4R,5R,6R)-6-[(1R)-1,2-dihydroxyethyl]-4,5-dihydroxy-2-methoxycarbonyloxan-2-yl]oxy-1-hydroxyethyl]-4,5-dihydroxy-2-prop-2-enoxyoxane-2-carboxylate