tetrasodium 3,3'-[(3,3'-diethoxy[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[5-(benzoylamino)-4-hydroxynaphthalene-2,7-disulphonate]

3,3'-[(3,3'-Diethoxy[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[5-(benzoylamino)-4-hydroxy-2,7-naphthalenedisulfonic acid]tetrasodium salt