benzyl 2-[(2S,7S)-7-(aminomethyl)-3-oxo-4-(2-phenylethyl)-1,4-diazepan-2-yl]acetate;benzyl 2-[(2S,7R)-7-ethyl-3-oxo-4-(2-phenylethyl)-1,4-diazepan-2-yl]acetate;benzyl (3S)-3-[(2-methylpropan-2-yl)oxycarbonylamino]-4-[[4-[(2-methylpropan-2-yl)oxycarbonylamino]-3-oxobutyl]-(2-phenylethyl)amino]-4-oxobutanoate;2-[(2S,7S)-7-[[[(2R)-5-(diaminomethylideneamino)-2-[(2-methylpropan-2-yl)oxycarbonylamino]pentanoyl]amino]methyl]-3-oxo-4-(2-phenylethyl)-1,4-diazepan-1-ium-2-yl]acetate