6492-56-4 Benzenesulfonic acid, 4-[[4-[(2,4-diaminophenyl)azo]phenyl]azo]-, monosodium salt Benzenesulfonic acid, p-[[p-[(2,4-diaminophenyl)azo]phenyl]azo]-, sodium salt C.I. 26220 NSC71958 Pontamine Brown D3G