InChI=1S/C21H20O12/c1-30-18-11(23)4-8-5-12(32-17(8)16(18)27)7-2-9(22)6-10(3-7)31-21-15(26)13(24)14(25)19(33-21)20(28)29/h2-6,13-15,19,21-27H,1H3,(H,28,29)