InChI=1S/C21H22O11/c1-28-11-5-3-10(4-6-12-7-13(29-2)9-15(22)30-12)14(8-11)31-21-18(25)16(23)17(24)19(32-21)20(26)27/h3-9,16-19,21,23-25H,1-2H3,(H,26,27)/b6-4+