The molecule is a pyrroloquinoline having hydroxy groups at the 4- and 5-positions and carboxy groups at the 2-, 7- and 9-positions. It is a tricarboxylic acid and a pyrroloquinoline cofactor. It is a conjugate acid of a pyrroloquinoline quinol(3-) and a pyrroloquinoline quinol(4-).
4,5-dihydroxy-6H-pyrrolo[2,3-f]quinoline-2,7,9-tricarboxylic acid