The molecule is a dicarboxylic acid dianion obtained by deprotonation of the carboxy groups of 2-oxohept-4-ene-1,7-dioic acid; major species at pH 7.3. It is a conjugate base of a 2-oxohept-4-ene-1,7-dioic acid. It is a tautomer of a 2-hydroxyhepta-2,4-dienedioate.
(E)-6-oxohept-3-enedioate