2,7-Naphthalenedisulfonic acid, 5-amino-4-hydroxy-3-((4'-((2-hydroxy-3,6-disulfo-1-naphthalenyl)azo)-3,3'-dimethoxy(1,1'-biphenyl)-4-yl)azo)-, tetrasodium salt 68084-09-3 EINECS 268-421-4 Tetrasodium 5-amino-4-hydroxy-3-((4'-((2-hydroxy-3,6-disulphonato-1-naphthyl)azo)-3,3'-dimethoxy(1,1'-biphenyl)-4-yl)azo)naphthalene-2,7-disulphonate