InChI=1S/C20H23NO3/c1-16(2)14-21-20(22)10-8-6-4-3-5-7-9-17-11-12-18-19(13-17)24-15-23-18/h4,6-13H,1,3,5,14-15H2,2H3,(H,21,22)/b6-4+,9-7+,10-8+