2,7-Naphthalenedisulfonic acid, 4-(acetylamino)-5-hydroxy-6-((4-((2-(sulfooxy)ethyl)sulfonyl)phenyl)azo)- 2,7-Naphthalenedisulfonic acid, 4-acetamido-5-hydroxy-6-((4-((2-hydroxyethyl)sulfonyl)phenyl)azo)-, hydrogen sulfate (ester) 68134-16-7