SMILES: C(=C\\C(=O)O)\\C(=O)/C=C/[O-]
Description: The molecule is an aldehydic acid anion resulting from the deprotonation of the carboxy group of (2Z,4E)-4-hydroxymuconic semialdehyde. It is a 6-oxo monocarboxylic acid anion and an aldehydic acid anion. It is a conjugate base of a (2Z,4E)-4-hydroxymuconic semialdehyde.