disodium 4-[[4-(acetylmethylamino)-2-sulphonatophenyl]amino]-1-amino-9,10-dihydro-9,10-dioxoanthracene-2-sulphonate

2-Anthracenesulfonic acid, 4-4-(acetylmethylamino)-2-sulfophenylamino-1-amino-9,10-dihydro-9,10-dioxo-, disodium salt