InChI=1S/C21H24O11/c1-2-3-6-11-10-5-4-7-12(16(10)20(28)30-11)31-21-19(27)18(26)17(25)13(32-21)9-29-15(24)8-14(22)23/h4-7,13,17-19,21,25-27H,2-3,8-9H2,1H3,(H,22,23)/b11-6+