SMILES: CC1=C(NC(=C1CCC(=O)O)N=NC2=CC=C(C=C2)S(=O)(=O)O)/C=C\\3/C(=C(C(=O)N3)C)C=C
Description: The molecule is a synthetic dipyrrin derived from rings A and D of bilirubin IXalpha in which C-9 carries a 2-(4-sulfophenyl)diazenyl substituent. It is an azo compound and a member of dipyrrins.