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

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

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

[1-((S)-2-Amino-3-methyl-butyryl)-piperidin-4-yl]-carbamic acid benzyl ester

[1-((S)-2-Amino-3-methyl-butyryl)-piperidin-4-yl]-methyl-carbamic acid benzyl ester

[1-((S)-2-Amino-3-methyl-butyryl)-piperidin-4-ylmethyl]-methyl-carbamic acid benzyl ester

[1-((S)-2-Amino-3-methyl-butyryl)-piperidin-4-yl]-ethyl-carbamic acid benzyl ester

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

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

((R)-3-Benzyloxycarbonylamino-piperidin-1-yl)-acetic acid

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