InChI=1S/C20H16O10S/c1-20(9-21)7-6-12-14(29-20)8-13(22)15-16(23)17(24)18(28-19(12)15)10-2-4-11(5-3-10)30-31(25,26)27/h2-8,21-22,24H,9H2,1H3,(H,25,26,27)