InChI=1S/C22H18O7/c1-27-21(25)17-18(22(26)28-2)20-16(12-5-9-14(24)10-6-12)15(19(17)29-20)11-3-7-13(23)8-4-11/h3-10,19-20,23-24H,1-2H3/t19-,20+