The molecule is an organophosphate oxoanion arising from deprotonation of the phosphate OH groups of D-ribose 1,5-diphosphate; major species at pH 7.3. It is a conjugate base of a D-ribose 1,5-bisphosphate.
[(3R,4S,5R)-3,4-dihydroxy-5-(phosphonatooxymethyl)oxolan-2-yl] phosphate