(R)-3-[((S)-2-Amino-propionyl)-cyclopropyl-amino]-pyrrolidine-1-carboxylic acid tert-butyl ester

(4-Benzyloxycarbonylamino-cyclohexylamino)-acetic acid

2-[(Carboxymethyl-amino)-methyl]-piperidine-1-carboxylic acid benzyl ester

3-[(Carboxymethyl-ethyl-amino)-methyl]-pyrrolidine-1-carboxylic acid benzyl ester

(1R,4R)-[(4-Benzyloxycarbonylamino-cyclohexyl)-ethyl-amino]-acetic acid

3-(Carboxymethyl-isopropyl-amino)-piperidine-1-carboxylic acid benzyl ester

3-[(Carboxymethyl-isopropyl-amino)-methyl]-piperidine-1-carboxylic acid benzyl ester

(R)-3-(Carboxymethyl-cyclopropyl-amino)-piperidine-1-carboxylic acid benzyl ester

4-(Carboxymethyl-cyclopropyl-amino)-piperidine-1-carboxylic acid benzyl ester

[(2-Benzyloxycarbonylamino-cyclohexyl)-cyclopropyl-amino]-acetic acid

3-{[(2-Hydroxy-ethyl)-methyl-amino]-methyl}-piperidine-1-carboxylic acid benzyl ester