InChI=1S/C20H21NO8/c1-8-7-10-9-5-3-4-6-11(9)21-12(10)17(16(8)27-2)28-20-15(24)13(22)14(23)18(29-20)19(25)26/h3-7,13-15,18,20-24H,1-2H3,(H,25,26)