ammonium 7-[[2-hydroxy-5-[(4-hydroxyphenyl)sulphonyl]phenyl]methyl](1-methylpropyl)naphthalene-2-sulphonate

7-[[2-Hydroxy-5-[(4-hydroxyphenyl)sulfonyl]phenyl]methyl](1-methylpropyl)-2-naphthalenesulfonic acid ammonium salt