[(S)-1-((S)-2-Amino-3-methyl-butyryl)-pyrrolidin-3-yl]-methyl-carbamic acid benzyl ester

[4-((S)-2-Amino-3-methyl-butyrylamino)-cyclohexyl]-methyl-carbamic acid benzyl ester

[1-((S)-2-Amino-3-methyl-butyryl)-pyrrolidin-2-ylmethyl]-isopropyl-carbamic acid benzyl ester

[1-((S)-2-Amino-3-methyl-butyryl)-pyrrolidin-3-yl]-isopropyl-carbamic acid benzyl ester

[1-((S)-2-Amino-3-methyl-butyryl)-pyrrolidin-2-ylmethyl]-cyclopropyl-carbamic acid benzyl ester

[4-((S)-2-Amino-3-methyl-butyrylamino)-cyclohexyl]-cyclopropyl-carbamic acid benzyl ester

(4-Benzyloxycarbonylamino-piperidin-1-yl)-acetic acid

[(S)-3-(Benzyloxycarbonyl-methyl-amino)-pyrrolidin-1-yl]-acetic acid

[2-(Benzyloxycarbonyl-methyl-amino)-cyclohexylamino]-acetic acid

[(S)-3-(Benzyloxycarbonyl-isopropyl-amino)-pyrrolidin-1-yl]-acetic acid

{3-[(Benzyloxycarbonyl-isopropyl-amino)-methyl]-pyrrolidin-1-yl}-acetic acid