SMILES: C1=C(C(=CC(=C1[O-])[O-])C(=O)O)C(=O)O
Description: The molecule is dicarboxylate anion of 4,5-dihydroxyphthalic acid; major species at pH 7.3. It is a conjugate base of a 4,5-dihydroxyphthalic acid.