InChI=1S/C21H20O14/c22-7(3-1-6-2-4-8(23)13(26)12(6)25)11-10(5-9(24)14(27)15(11)28)34-21-18(31)16(29)17(30)19(35-21)20(32)33/h1-5,16-19,21,23-31H,(H,32,33)/b3-1+