InChI=1S/C16H13N3O7S2/c17-12-8-11(27(21,22)23)6-9-7-13(28(24,25)26)15(16(20)14(9)12)19-18-10-4-2-1-3-5-10/h1-8,20H,17H2,(H,21,22,23)(H,24,25,26)/b19-18+