2-(4-Dipropylaminophenylazo)benzoic acid 2641-01-2 Benzoic acid, 2-((4-(dipropylamino)phenyl)azo)- Benzoic acid, o-((p-(dipropylamino)phenyl)azo)- EINECS 220-140-8 EK-944 NSC 7803 Propyl red