InChI=1S/C18H20N2O6/c19-13(17(22)23)7-10-1-4-12(5-2-10)26-16-9-11(3-6-15(16)21)8-14(20)18(24)25/h1-6,9,13-14,21H,7-8,19-20H2,(H,22,23)(H,24,25)/t13-,14?/m0/s1