502-02-3 Benzenesulfonic acid, 4-[[4-(dimethylamino)phenyl]azo]- Benzenesulfonic acid, p-[[p-(dimethylamino)phenyl]azo]- Methyl orange NSC9595 p-(p'-Dimethylaminophenylazo)benzene sulfonate p-[[p-(Dimethylamino)phenyl]azo]benzenesulfonic acid