InChI=1S/C20H21NO7/c1-19(27)8-4-3-5-11(22)14(8)17(25)15-9(19)6-10-16(21-2)12(23)7-13(24)20(10,28)18(15)26/h3-5,9-10,15-16,21-22,27-28H,6-7H2,1-2H3/t9?,10?,15?,16?,19-,20-/m1/s1