InChI=1S/C16H10N2O5S/c19-15-9-3-1-2-4-11(9)17-14(15)13-10-7-8(24(21,22)23)5-6-12(10)18-16(13)20/h1-7,17H,(H,18,20)(H,21,22,23)/b14-13-