disodium 2-[[5-carbamoyl-1,6-dihydro-2-hydroxy-4-methyl-6-oxo-1-[2-(4-sulphonatophenyl)ethyl]-3-pyridyl]azo]-5-[(3-phosphonophenyl)azo]benzenesulphonate

2-[[[5-(Aminocarbonyl)-1,6-dihydro-2-hydroxy-4-methyl-6-oxo-1-[2-[4-(sodiosulfo)phenyl]ethyl]pyridin]-3-yl]azo]-5-[(3-phosphonophenyl)azo]benzenesulfonic acid 1-sodium salt