The molecule is a lipid A oxoanion arising from deprotonation of the phosphate OH groups and protonation of the amino group of lipid IIB; major species at pH 7.3. It is a conjugate base of a lipid IIB.
[(2R,3S,4R,5R,6R)-6-[[(2R,3S,4R,5R,6R)-6-[[(2R,3R,4S,5S)-5-azaniumyl-3,4-dihydroxyoxan-2-yl]oxy-oxidophosphoryl]oxy-5-[[(3R)-3-hexadecanoyloxytetradecanoyl]amino]-3-hydroxy-4-[(3R)-3-hydroxytetradecanoyl]oxyoxan-2-yl]methoxy]-2-(hydroxymethyl)-5-[[(3R)-3-hydroxytetradecanoyl]amino]-4-[(3R)-3-hydroxytetradecanoyl]oxyoxan-3-yl] phosphate