1-Oxa-2,7-diazaspiro[4.4]non-2-ene-8-carboxamide, 3-(4-chlorophenyl)-7-[(2S)-2-[(2-cyclohexylacetyl)amino]-3,3-dimethyl-1- oxobutyl]-N-[(1S)-1-[2-(cyclopropylamino)-2-oxoacetyl]butyl]-, (5S,8S)-