InChI=1S/C18H16N4O9S2/c1-9-7-11(32(26,27)28)4-6-15(9)22-17(23)16(10(2)21-22)20-19-14-8-12(33(29,30)31)3-5-13(14)18(24)25/h3-8,23H,1-2H3,(H,24,25)(H,26,27,28)(H,29,30,31)/b20-19+