InChI=1S/C22H20O7/c1-12(23)29-22-10-13-4-5-16-14(6-7-26-16)21(13)28-20(22)11-27-17-9-19(25-3)18(24-2)8-15(17)22/h4-9,20H,10-11H2,1-3H3