InChI=1S/C15H13N3O4S2/c1-17-24(20,21)11-5-2-9(3-6-11)12-7-4-10(22-12)8-13-14(19)18-15(16)23-13/h2-8,17H,1H3,(H2,16,18,19)/b13-8-