InChI=1/C21H26O9/c1-5-21(2,3)11-6-10-7-13(27-4)14(8-12(10)28-19(11)26)29-20-18(25)17(24)16(23)15(9-22)30-20/h5-8,15-18,20,22-25H,1,9H2,2-4H3