InChI=1S/C21H24O9S/c1-13(16(22)11-21(2,3)12-29-31(24,25)26)6-8-28-20-14-4-5-19(23)30-18(14)10-17-15(20)7-9-27-17/h4-7,9-10,16,22H,8,11-12H2,1-3H3,(H,24,25,26)/b13-6+