tert-butyl N-[(2R)-1-[(2S)-2-[[(2S)-5-(diaminomethylideneamino)-1-oxopentan-2-yl]carbamoyl]pyrrolidin-1-yl]-1-oxo-3-phenylpropan-2-yl]carbamate
tert-butyl N-[(1R)-2-[(2S)-2-[[(1S)-1-formyl-4-guanidino-butyl]carbamoyl]pyrrolidin-1-yl]-2-oxo-1-(phenylmethyl)ethyl]carbamate
N-[(1R)-2-[(2S)-2-[[[(1S)-1-formyl-4-guanidinobutyl]amino]-oxomethyl]-1-pyrrolidinyl]-2-oxo-1-(phenylmethyl)ethyl]carbamic acid tert-butyl ester
N-[(1R)-1-(benzyl)-2-[(2S)-2-[[(1S)-1-formyl-4-guanidino-butyl]carbamoyl]pyrrolidin-1-yl]-2-keto-ethyl]carbamic acid tert-butyl ester
tert-butyl N-[(2R)-1-[(2S)-2-[[(2S)-5-(diaminomethylideneamino)-1-oxo-pentan-2-yl]carbamoyl]pyrrolidin-1-yl]-1-oxo-3-phenyl-propan-2-yl]carbamate