InChI=1S/C21H20O12/c1-6-3-8(22)12-9(32-21-17(27)15(25)16(26)19(33-21)20(28)29)4-7-5-10(30-2)13(23)14(24)11(7)18(12)31-6/h3-5,15-17,19,21,23-27H,1-2H3,(H,28,29)