InChI=1S/C25H18O6/c1-9-6-14-18(15(27)7-9)24(30)21-16(28)8-10(2)17-13-5-4-12(11(3)26)23(29)20(13)25(31)19(14)22(17)21/h4-8,26,28-30H,1-3H3