InChI=1S/C20H20O11/c21-10-6-9(14(24)12(23)7-10)3-1-8-2-4-13(11(22)5-8)30-20-17(27)15(25)16(26)18(31-20)19(28)29/h1-7,15-18,20-27H,(H,28,29)/b3-1+