2484-88-0 4-(PHENYLAZO)BENZENESULFONIC ACID Azobenzene-4-sulfonic acid Azobenzene-4-sulphonic acid Benzenesulfonic acid, 4-(phenylazo)- Benzenesulfonic acid, p-(phenylazo)- EINECS 219-624-1 NSC 1847 p-(Phenylazo)benzenesulfonic acid