2,2-(1,3,5,7-tetraoxo-5,7-dihydropyrrolo(3,4-f)isoindole-2,6(1H,3H)diyl)dibenzoic acid

2,2-(1,3,5,7-tetraoxo-5,7-dihydropyrrolo(3,4-f)isoindole-2,6(1H,3H)diyl)dibenzoic acid · CAS 37881-74-6