InChI=1S/C21H12O12/c1-31-19(28)11-5-7-3-9(23)15(17(25)13(7)21(30)33-11)14-8(22)2-6-4-10(18(26)27)32-20(29)12(6)16(14)24/h2-5,22-25H,1H3,(H,26,27)