InChI=1S/C18H18N4O4/c1-21-14-6-5-12(10-13(14)20-16(21)11-23)18(26)22(9-7-17(24)25)15-4-2-3-8-19-15/h2-6,8,10,23H,7,9,11H2,1H3,(H,24,25)