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

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

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

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

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

{(S)-2-[(Benzyloxycarbonyl-methyl-amino)-methyl]-pyrrolidin-1-yl}-acetic acid

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

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

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

{(S)-2-[(Benzyloxycarbonyl-isopropyl-amino)-methyl]-pyrrolidin-1-yl}-acetic acid

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