7-(2-chlorophenyl)-6b-cyano-4a,6a-dimethyl-1,2,3,4,4a,4b,5,6,6a,6b,7,7a,8,8a,8b,9-hexadecahydronaphtho[2',1':4,5]indeno[1,2-b]aziren-2-yl acetate