InChI=1S/C21H28O8/c1-3-4-9-29-20(26)21(27)11-14(19(25)17(24)12-21)15(22)7-5-13-6-8-16(23)18(10-13)28-2/h5-8,10,14,17,19,23-25,27H,3-4,9,11-12H2,1-2H3/b7-5+/t14-,17+,19-,21+/m0/s1