51473-76-8 EINECS 257-228-0 Tetrasodium 4-amino-3-((4-(2-(4-((2,4-diaminophenyl)azo)-2-sulphonatophenyl)vinyl)-3-sulphonatophenyl)azo)-5-hydroxy-6-(phenylazo)naphthalene-2,7-disulphonate