di-tert-butyl 5,5'-((12-chloro-6-phenethyl-6H-benzo[5,6][1,3]oxazino[3,4-a]indole-3,10-diyl)bis(1H-imidazole-5,2-diyl))(3R,3'R,5S,5'S)-bis(3-fluoropyrrolidine-1-carboxylate)