InChI=1S/C15H20N2O8/c1-5(16)8(17)6-3-2-4-7(18)12(6)24-15-11(21)9(19)10(20)13(25-15)14(22)23/h2-4,9-11,13,15,18-21H,16-17H2,1H3,(H,22,23)/b8-5-