InChI=1S/C13H14N2O6/c14-11(18)9(5-6-10(16)17)15-12(19)7-3-1-2-4-8(7)13(20)21/h1-4,9H,5-6H2,(H2,14,18)(H,15,19)(H,16,17)(H,20,21)