InChI=1S/C21H22O12/c1-29-11-7-10(31-13(22)8-11)5-3-9-4-6-12(18(30-2)14(9)23)32-21-17(26)15(24)16(25)19(33-21)20(27)28/h3-8,15-17,19,21,23-26H,1-2H3,(H,27,28)/b5-3+