InChI=1S/C22H24N2O7/c25-16-6-3-14(11-18(16)27)4-7-21(30)23-9-1-2-10-24-22(31)8-5-15-12-19(28)20(29)13-17(15)26/h3-8,11-13,25-29H,1-2,9-10H2,(H,23,30)(H,24,31)/b7-4+,8-5?