1,5-Bis(2-methoxy-4-nitro-5-sulfophenyl)-3-((phenylamino)carbonyl)formazan 70709-62-5 Benzenesulfonic acid, 3,3'-(3-((phenylamino)carbonyl)-1,5-formazandiyl)bis(4-methoxy-6-nitro- Xtt formazan