Dutasteride Chloro Impurity

(4aR,4bS,6aS,7S,9aS,9bS,11aR)-N-[2,5-Bis(trifluoromethyl)phenyl]-4-chlorohexadecahydro-4a,6a-dimethyl-2-oxo-1H-indeno[5,4-f]quinoline-7-carboxamide