InChI=1S/C21H16F2N2O4/c1-2-21(28)7-18(26)29-9-12-13(21)5-17-19-11(8-25(17)20(12)27)3-10-4-14(22)15(23)6-16(10)24-19/h3-6,28H,2,7-9H2,1H3/t21-/m1/s1