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.
(Z)-2-hydroxy-3-[(E)-3-oxoprop-1-enyl]but-2-enedioic acid