InChI=1/C11H12N2O6/c14-9(15)5-12-2-1-6-3-7(10(16)17)13-8(4-6)11(18)19/h1-3,8,13H,4-5H2,(H,14,15)(H,16,17)(H,18,19)/b6-1-,12-2-/t8-/s2