InChI=1S/C21H30O9/c1-5-9-13-10(7(2)3)6-11(22)8(4)12(13)18(14(9)23)29-21-17(26)15(24)16(25)19(30-21)20(27)28/h5,7,10-13,15-19,21-22,24-26H,4,6H2,1-3H3,(H,27,28)/b9-5+