1,3-isobenzofurandione, 4,5,6,7-tetrafluoro- 4,5,6,7-tetrafluoro-2-benzofuran-1,3-dione InChI=1/C8F4O3/c9-3-1-2(8(14)15-7(1)13)4(10)6(12)5(3)1