tetrasodium 5,5'-(carbonyldiimino)bis[8-[[4-[(4-sulphonatophenyl)azo]phenyl]azo]naphthalene-2-sulphonate]

5,5'-(Carbonyldiimino)bis[8-[[4-[(4-sulfophenyl)azo]phenyl]azo]-2-naphthalenesulfonic acid]tetrasodium salt