InChI=1S/C20H18O12/c1-29-6-2-9(22)13-12(3-6)30-10-5-8(21)11(4-7(10)14(13)23)31-20-17(26)15(24)16(25)18(32-20)19(27)28/h2-5,15-18,20-22,24-26H,1H3,(H,27,28)