Also Called: 2,7-Naphthalenedisulfonic acid, 5-amino-4-hydroxy-3-[[4-[ [4-[[4-hydroxy-2-(phenylamino)phenyl]azo]phenyl]amino ]phenyl]azo]-, sodium salt;2,7-Naphthalenedisulfonic acid, 5-amino-4-hydroxy-3-[[4-[[4-[[4-hydroxy-2-(phenylamino)phenyl]azo]phenyl]amino]phenyl]azo]-, sodium salt