5-Carb­oxy-1,3-bis­(carb­oxy­meth­yl)-4-imidazolinium-4-carboxyl­ate

The title compound, C₉H₈N₂O₈, was obtained by the reaction of imidazole-4,5-dicarb­oxy­lic acid and 2-chloro­acetic acid. An intra­molecular O—H...O hydrogen bond occurs. The crystal packing is stabilized by intermolecular O—H...O and C—H...O hydrogen bonds, which link mol­ecules into a three-dimensional network.