InChI=1S/C14H11N3O4S2/c15-14-17-13(18)12(22-14)7-9-3-6-11(21-9)8-1-4-10(5-2-8)23(16,19)20/h1-7H,(H2,15,17,18)(H2,16,19,20)/b12-7-