tetrasodium 7,7'-(carbonyldiimino)bis[4-hydroxy-3-[(6-sulphonato-2-naphthyl)azo]naphthalene-2-sulphonate]

7,7'-Ureylenebis[4-hydroxy-3-[(6-sodiooxysulfonyl-2-naphthalenyl)azo]-2-naphthalenesulfonic acid sodium] salt

2-Naphthalenesulfonic acid, 7,7-(carbonyldiimino)bis4-hydroxy-3-(6-sulfo-2-naphthalenyl)azo-, tetrasodium salt