InChI=1S/C16H16O11S/c17-10-3-1-8(5-12(10)27-28(23,24)25)2-4-14(19)26-13-7-9(16(21)22)6-11(18)15(13)20/h1-6,11,13,15,17-18,20H,7H2,(H,21,22)(H,23,24,25)/b4-2+