2,7-Naphthalenedisulfonic acid,4-amino-6-[(4-dodecylphenyl)azo]-5-hydroxy-3-[[5-[[3-[[[3-[(1-hydroxy-8-sulfo-2-naphthalenyl)azo]-4-sulfophenyl]amino]carbonyl]benzoyl]amino]-2-sulfophenyl]azo]-