InChI=1S/C19H18O11S/c1-10(20)28-8-19(9-29-16-7-12(21)6-13(22)17(16)18(19)23)11-3-4-14(27-2)15(5-11)30-31(24,25)26/h3-7,21-22H,8-9H2,1-2H3,(H,24,25,26)