InChI=1S/C18H20N2O4/c19-16(18(22)23)10-11-17(21)20-14-6-8-15(9-7-14)24-12-13-4-2-1-3-5-13/h1-9,16H,10-12,19H2,(H,20,21)(H,22,23)/t16-/m0/s1