SMILES: C(=C/C(=C(\\C(=O)O)/O)/C(=O)O)\\C=O
Description: The molecule is a carboxy-2-hydroxymuconate semialdehyde having the carboxy group at the 3-position. It is a conjugate acid of a 2-hydroxy-3-(3-oxoprop-1-enyl)but-2-enedioate.