InChI=1S/C21H22O7/c1-13(5-8-21(2,12-22)20(24)25)6-9-27-19-14-3-4-18(23)28-17(14)11-16-15(19)7-10-26-16/h3-4,6-7,10-11,22H,5,8-9,12H2,1-2H3,(H,24,25)/b13-6+