InChI=1S/C20H18O7/c1-20(2,25)16-6-11-14(27-16)7-15-17(18(11)23)19(24)12(8-26-15)10-4-3-9(21)5-13(10)22/h3-5,7-8,16,21-23,25H,6H2,1-2H3/t16-/m0/s1