tetrasodium 7,7'-(carbonyldiimino)bis[4-hydroxy-3-[(2-methyl-4-sulphonatophenyl)azo]naphthalene-2-sulphonate]

7,7'-Ureylenebis[4-hydroxy-3-[[2-methyl-4-(sodiooxysulfonyl)phenyl]azo]-2-naphthalenesulfonic acid sodium] salt

2-Naphthalenesulfonic acid, 7,7'-(carbonyldiimino)bis[ 4-hydroxy-3-[(2-methyl-4-sulfophenyl)azo]-, tetrasodium salt