InChI=1S/C20H20O7/c1-9-6-12(11-3-2-10(21)8-16(11)24)17(20(26)27)13(7-9)18-14(22)4-5-15(23)19(18)25/h2-5,7-8,12-13,17,21-25H,6H2,1H3,(H,26,27)