(3S,3aR,9S,10aR,12aR,12bS)-N,3a,10,10,12b-pentamethyl-3-[(1R)-1-(propan-2-ylideneamino)ethyl]-1,2,3,3a,4,7,8,9,10,10a,11,12,12a,12b-tetradecahydrobenzo[4,5]cyclohepta[1,2-e]inden-9-amine