InChI=1S/C20H18O13S/c21-9-3-1-2-8(4-9)18-19(16(25)14-11(23)5-10(22)6-12(14)31-18)33-20-17(26)15(24)13(32-20)7-30-34(27,28)29/h1-6,13,15,17,20-24,26H,7H2,(H,27,28,29)