InChI=1S/C21H22O11/c1-30-14-5-3-9(6-12(14)22)2-4-10-7-11(8-13(23)15(10)24)31-21-18(27)16(25)17(26)19(32-21)20(28)29/h2-8,16-19,21-27H,1H3,(H,28,29)/b4-2+