(S)-2-(2-Amino-ethylsulfanylmethyl)-pyrrolidine-1-carboxylic acid tert-butyl ester

4-(Carboxymethyl-ethyl-amino)-piperidine-1-carboxylic acid tert-butyl ester

(R)-3-(Carboxymethyl-isopropyl-amino)-pyrrolidine-1-carboxylic acid tert-butyl ester

(1R,4R)-[(4-tert-Butoxycarbonylamino-cyclohexyl)-isopropyl-amino]-acetic acid

[(2-tert-Butoxycarbonylamino-cyclohexyl)-cyclopropyl-amino]-acetic acid

3-(2-Chloro-acetylamino)-piperidine-1-carboxylic acid tert-butyl ester

(R)-3-[(2-Chloro-acetyl)-methyl-amino]-pyrrolidine-1-carboxylic acid tert-butyl ester

(S)-3-[(2-Chloro-acetyl)-methyl-amino]-piperidine-1-carboxylic acid tert-butyl ester

(S)-3-[(2-Chloro-acetyl)-ethyl-amino]-pyrrolidine-1-carboxylic acid tert-butyl ester

(R)-3-[(2-Chloro-acetyl)-isopropyl-amino]-pyrrolidine-1-carboxylic acid tert-butyl ester

(1R,4R)-{4-[(2-Chloro-acetyl)-isopropyl-amino]-cyclohexyl}-carbamic acid tert-butyl ester