The molecule is dicarboxylate anion of 5-formyl-2-hydroxyhepta-2,4-dienedioic acid; major species at pH 7.3. It is a conjugate base of a 5-formyl-2-hydroxyhepta-2,4-dienedioic acid.
(E,3Z)-7-hydroxy-3-(oxidomethylidene)-6,7-dioxohept-4-enoate