[(S)-1-((S)-2-Amino-propionyl)-piperidin-3-yl]-isopropyl-carbamic acid benzyl ester

[1-((S)-2-Amino-propionyl)-piperidin-4-yl]-isopropyl-carbamic acid benzyl ester

[1-((S)-2-Amino-propionyl)-piperidin-3-ylmethyl]-cyclopropyl-carbamic acid benzyl ester

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

(1R,4R)-[4-((S)-2-Amino-3-methyl-butyrylamino)-cyclohexyl]-methyl-carbamic acid benzyl ester

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

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

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

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

((S)-3-Benzyloxycarbonylamino-pyrrolidin-1-yl)-acetic acid

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