1,2,4,5-Benzenetetracarboxylic 1,2:4,5-diimide 1,2,4,5-Benzenetetracarboxylic acid diimide 2550-73-4 Benzo[1,2-c:4,5-c']dipyrrole-1,3,5,7(2H,6H)-tetrone NSC55160 Pyromellitic acid diimide Pyromellitic diimide Pyromellitimide