(1R,4R)-{4-[(2-Amino-acetyl)-methyl-amino]-cyclohexyl}-carbamic acid benzyl ester

{2-[(2-Amino-acetyl)-cyclopropyl-amino]-cyclohexyl}-carbamic acid benzyl ester

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

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

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

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

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

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

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

3-[((S)-2-Amino-3-methyl-butyrylamino)-methyl]-pyrrolidine-1-carboxylic acid benzyl ester

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