InChI=1S/C20H21NO/c21-20(19(22)15-9-5-2-6-10-15)17-12-11-16(13-17)18(20)14-7-3-1-4-8-14/h1-10,16-18H,11-13,21H2/t16-,17+,18+,20+/m0/s1