The molecule is a tripyrrole that is an oxidized metabolite of bilirubin, in which methyl groups are present at positions 3, 7 and 13 with a vinyl group at position 2. It derives from a hydride of a tripyrrin.
3-[2-[[3-(2-carboxyethyl)-5-hydroxy-4-methyl-1H-pyrrol-2-yl]methylidene]-5-[(4-ethenyl-3-methyl-5-oxopyrrol-2-yl)methylidene]-4-methylpyrrol-3-yl]propanoic acid