4-[(6-{[4-({6-[(4-Carboxyphenyl)diazenyl]-5-hydroxy-7-sulfo(2-naphthyl)}amino)-2,3-dioxocyclobut-1(4)-enyl]amino}-1-hydroxy-3-sulfo-2-naphthyl)diazenyl]benzoic acid AIDS-104473 AIDS104473