The molecule is a linear tetrapyrrole anion obtained by deprotonation of both the carboxy groups of 15-oxo-beta-bilirubin. It is a linear tetrapyrrole anion and a dicarboxylic acid dianion. It is a conjugate base of a 15-oxo-beta-bilirubin.
3-[(2Z)-2-[[3-(2-carboxylatoethyl)-5-[4-ethenyl-5-[(Z)-(4-ethenyl-3-methyl-5-oxopyrrol-2-ylidene)methyl]-3-methyl-1H-pyrrole-2-carbonyl]-4-methyl-1H-pyrrol-2-yl]methylidene]-4-methyl-5-oxopyrrol-3-yl]propanoate