2,6-Bis(3-hydroxyphenyl)benzo[1,2-c:4,5-c']dipyrrole-1,3,5,7(2H,6H)-tetrone

2,6-Bis(3-hydroxyphenyl)-1,3,5,7-tetraoxo-1,2,3,5,6,7-hexahydrobenzo[1,2-c:4,5-c']dipyrrole