InChI=1S/C16H16O9S/c17-10(18)4-2-1-3-8-5-6-9(26-8)7-24-16-13(21)11(19)12(20)14(25-16)15(22)23/h2,4-6,11-14,16,19-21H,7H2,(H,17,18)(H,22,23)/b4-2+