InChI=1S/C21H24O12/c1-28-13-7-10(4-2-9-3-5-11-12(6-9)30-8-29-11)31-20(27)17(13)32-21-16(24)14(22)15(23)18(33-21)19(25)26/h2-6,10,13-18,21-24H,7-8H2,1H3,(H,25,26)/b4-2+