2,7-Naphthalenedisulfonic acid, 4-amino-3,6-[bis(4-nitrophenyl)azo]-5-hydroxy-, disodium salt 2,7-Naphthalenedisulfonic acid, 4-amino-5-hydroxy-3,6-bis[(4-nitrophenyl)azo]-, disodium salt 68084-24-2 NSC65544