InChI=1S/C20H25NO2/c1-21-13-12-20(16-6-4-3-5-7-16)17(14-21)15-23-19-10-8-18(22-2)9-11-19/h3-11,17,20H,12-15H2,1-2H3/t17-,20-/m1/s1