InChI=1S/C15H18O11S/c16-9-4-1-8(2-5-9)3-6-11(17)26-15-14(20)13(19)12(18)10(25-15)7-24-27(21,22)23/h1-6,10,12-16,18-20H,7H2,(H,21,22,23)/b6-3+