InChI=1S/C21H26O9S/c1-11-12(2)20(14-9-17(26-3)21(28-5)18(10-14)27-4)29-19(11)13-6-7-15(22)16(8-13)30-31(23,24)25/h6-12,19-20,22H,1-5H3,(H,23,24,25)