The molecule is a 6-oxo monocarboxylic acid anion resulting from the deprotonation of the carboxy group of (2Z,4E)-2-hydroxy-5-methyl-6-oxohexa-2,4-dienoic acid. The major species at pH 7.3. It is a conjugate base of a (2Z,4E)-2-hydroxy-5-methyl-6-oxohexa-2,4-dienoic acid.
(1Z,3E)-6-hydroxy-2-methyl-5,6-dioxohexa-1,3-dien-1-olate