InChI=1S/C20H20N2O6/c1-27-14-7-10(6-12(23)18(14)24)19-17(20(25)26)16-13(28-19)3-2-11-15(16)9(4-5-21)8-22-11/h2-3,6-8,17,19,22-24H,4-5,21H2,1H3,(H,25,26)