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

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

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

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

{2-[((S)-2-Amino-3-methyl-butyryl)-ethyl-amino]-cyclohexyl}-carbamic acid benzyl ester

((R)-1-Benzyl-piperidin-3-ylamino)-acetic acid

[((S)-1-Benzyl-pyrrolidin-2-ylmethyl)-methyl-amino]-acetic acid

[((S)-1-Benzyl-pyrrolidin-3-yl)-ethyl-amino]-acetic acid

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

[(1-Benzyl-piperidin-3-ylmethyl)-isopropyl-amino]-acetic acid

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