InChI=1S/C28H22O6/c29-18-5-1-15(2-6-18)9-23-24-13-22(33)14-25(34)28(24)27(17-10-20(31)12-21(32)11-17)26(23)16-3-7-19(30)8-4-16/h1-14,26-27,29-34H/b23-9+