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

(S)-2-Amino-1-[(R)-3-(benzyl-cyclopropyl-amino)-piperidin-1-yl]-3-methyl-butan-1-one

(S)-2-Amino-1-[4-(benzyl-cyclopropyl-amino)-piperidin-1-yl]-3-methyl-butan-1-one

3-[(2-Amino-acetyl)-isopropyl-amino]-piperidine-1-carboxylic acid tert-butyl ester

2-{[(2-Amino-acetyl)-isopropyl-amino]-methyl}-piperidine-1-carboxylic acid tert-butyl ester

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

(R)-3-((S)-2-Amino-propionylamino)-pyrrolidine-1-carboxylic acid tert-butyl ester

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

(R)-3-((S)-2-Amino-propionylamino)-piperidine-1-carboxylic acid tert-butyl ester

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

{4-[((S)-2-Amino-propionyl)-methyl-amino]-cyclohexyl}-carbamic acid tert-butyl ester