1,7-Dioxa-2,6-diaza-4,4-dioxide-4,7a-dithia-3H,5H-benzo(cd)pentalene 5H,7H-2,3-Dioxa-2alambda4,6-dithia-1,4-diazacyclopent(cd)indene, 6,6-dioxide 85579-27-7 Hep-IV