(2S)-2-amino-5-[3-(phenylmethoxycarbonylamino)pyrrolidin-1-yl]pentanoic acid;(2R)-2-amino-N-quinolin-3-yl-3-[4-(trifluoromethyl)phenyl]propanamide;benzyl N-pyrrolidin-3-ylcarbamate;tert-butyl (2-methylpropan-2-yl)oxycarbonyl carbonate;tert-butyl N-[(2-methylpropan-2-yl)oxycarbonyl]-N-[(2R)-5-[3-(phenylmethoxycarbonylamino)pyrrolidin-1-yl]pentan-2-yl]carbamate;(2S)-2-[(2-methylpropan-2-yl)oxycarbonylamino]-5-[3-(phenylmethoxycarbonylamino)pyrrolidin-1-yl]pentanoic acid