InChI=1S/C19H14N2O6/c1-10(22)27-16(11-6-3-2-4-7-11)19(26)20-13-9-5-8-12-14(13)15(23)18(25)21-17(12)24/h2-9,16H,1H3,(H,20,26)(H,21,24,25)/t16-/m0/s1