InChI=1S/C18H14N4O3S2/c23-17-15(14-3-1-2-4-16(14)21-17)11-20-12-5-7-13(8-6-12)27(24,25)22-18-19-9-10-26-18/h1-11,20H,(H,19,22)(H,21,23)/b15-11-