4-{[(2-Amino-acetyl)-methyl-amino]-methyl}-piperidine-1-carboxylic acid benzyl ester

3-[(2-Amino-acetyl)-cyclopropyl-amino]-piperidine-1-carboxylic acid benzyl ester

2-[((S)-2-Amino-propionylamino)-methyl]-pyrrolidine-1-carboxylic acid benzyl ester

(1R,4R)-[4-((S)-2-Amino-propionylamino)-cyclohexyl]-carbamic acid benzyl ester

[2-((S)-2-Amino-propionylamino)-cyclohexyl]-carbamic acid benzyl ester

(R)-3-[((S)-2-Amino-propionyl)-ethyl-amino]-pyrrolidine-1-carboxylic acid benzyl ester

4-[((S)-2-Amino-propionyl)-ethyl-amino]-piperidine-1-carboxylic acid benzyl ester

3-[((S)-2-Amino-propionyl)-isopropyl-amino]-piperidine-1-carboxylic acid benzyl ester

(1R,4R)-{4-[((S)-2-Amino-propionyl)-isopropyl-amino]-cyclohexyl}-carbamic acid benzyl ester

2-{[((S)-2-Amino-propionyl)-cyclopropyl-amino]-methyl}-piperidine-1-carboxylic acid benzyl ester

(R)-3-((S)-2-Amino-3-methyl-butyrylamino)-piperidine-1-carboxylic acid benzyl ester