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

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

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

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

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

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

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

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

[4-(Benzyloxycarbonyl-ethyl-amino)-piperidin-1-yl]-acetic acid

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

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