InChI=1S/C21H18O9/c22-13-11-8-4-5-9-12(11)28-17(10-6-2-1-3-7-10)18(13)29-21-16(25)14(23)15(24)19(30-21)20(26)27/h1-9,14-16,19,21,23-25H,(H,26,27)