has role has role is conjugate base of independent continuant bilirubin IXalpha dicarboxylic acid dianion bilirubin(2-) chebi_ontology (4Z,15Z)-bilirubin IXalpha A dicarboxylic acid dianion obtained by deprotonation of the two carboxy groups of bilirubin; major species at pH 7.3. bilirubin dianion (4Z,15Z)-bilirubin IX-alpha 2,7,13,17-tetramethyl-1,19-dioxo-3,18-divinyl-1,10,19,22,23,24-hexahydro-21H-biline-8,12-dipropanoate CHEBI:57977 linear tetrapyrrole anion human metabolite