InChI=1S/C20H18O11S/c1-20(2)14(31-32(26,27)28)4-8-3-10(17(24)18(25)19(8)30-20)11-7-29-13-6-9(21)5-12(22)15(13)16(11)23/h3,5-7,14,21-22,24-25H,4H2,1-2H3,(H,26,27,28)