3-[((S)-2-Amino-3-methyl-butyrylamino)-methyl]-piperidine-1-carboxylic acid tert-butyl ester

3-[((S)-2-Amino-3-methyl-butyryl)-cyclopropyl-amino]-piperidine-1-carboxylic acid tert-butyl ester

3-{[((S)-2-Amino-3-methyl-butyryl)-cyclopropyl-amino]-methyl}-piperidine-1-carboxylic acid tert-butyl ester

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

(R)-3-(Carboxymethyl-ethyl-amino)-pyrrolidine-1-carboxylic acid benzyl ester

(S)-2-[(Carboxymethyl-isopropyl-amino)-methyl]-pyrrolidine-1-carboxylic acid benzyl ester

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

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

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

{4-[(2-Hydroxy-ethyl)-methyl-amino]-cyclohexyl}-carbamic acid benzyl ester

(S)-3-[Ethyl-(2-hydroxy-ethyl)-amino]-piperidine-1-carboxylic acid benzyl ester