InChI=1S/C16H18N2O9/c19-13(9-26-10-4-2-1-3-5-10)17-12(16(24)25)8-27-18-11(15(22)23)6-7-14(20)21/h1-5,12H,6-9H2,(H,17,19)(H,20,21)(H,22,23)(H,24,25)/b18-11+/t12-/m0/s1