InChI=1S/C20H21NO6/c1-21-6-5-10-7-15(24-2)13(22)8-12(10)18-17(21)11-3-4-14-19(26-9-25-14)16(11)20(23)27-18/h3-4,7-8,17-18,20,22-23H,5-6,9H2,1-2H3