trisodium 4-amino-3-[[4-[[4-[(2,4-dihydroxyphenyl)azo]phenyl]amino]-3-sulphonatophenyl]azo]-5-hydroxy-6-(phenylazo)naphthalene-2,7-disulphonate

4-Amino-3-[[4-[[4-[(2,4-dihydroxyphenyl)azo]phenyl]amino]-3-sulfophenyl]azo]-5-hydroxy-6-(phenylazo)-2,7-naphthalenedisulfonic acid trisodium salt