InChI=1S/C29H20O11S/c30-18-8-5-15(6-9-18)4-7-16-10-19(31)13-23-25(16)29(28(34)39-23)26-22(33)12-20(32)14-24(26)38-27(29)17-2-1-3-21(11-17)40-41(35,36)37/h1-14,27,30-33H,(H,35,36,37)/b7-4+