diammonium 7-acetamido-4-hydroxy-3-[[4-[(4-sulphonatophenyl)azo]phenyl]azo]naphthalene-2-sulphonate

7-(Acetylamino)-4-hydroxy-3-[[4-[[4-(ammoniosulfo)phenyl]azo]phenyl]azo]-2-naphthalenesulfonic acid ammonium salt