InChI=1S/C11H12N2O7/c14-5-8(12-10(16)11(17)18)9(15)6-1-3-7(4-2-6)13(19)20/h1-4,8-9,14-15H,5H2,(H,12,16)(H,17,18)/t8-,9-/m1/s1