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

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

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

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

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

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

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

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

(1-Benzyl-pyrrolidin-3-ylamino)-acetic acid

[(1-Benzyl-piperidin-4-ylmethyl)-amino]-acetic acid

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