InChI=1S/C20H21NO6/c1-23-15-7-10-5-6-21-17-11-3-4-14-19(26-9-25-14)16(11)20(24-2)27-18(17)12(10)8-13(15)22/h3-4,7-8,17-18,20-22H,5-6,9H2,1-2H3/t17-,18?,20?/m1/s1