7-[[3-(acetamido)benzoyl]amino]-4-hydroxy-3-[[2-methyl-4-[(2-methyl-4-sulphophenyl)azo]phenyl]azo]naphthalene-2-sulphonic acid, sodium salt

7-[[3-(Acetylamino)benzoyl]amino]-4-hydroxy-3-[[2-methyl-4-[(2-methyl-4-sulfophenyl)azo]phenyl]azo]-2-naphthalenesulfonic acid/sodium,(1:x) salt