[(S)-1-((S)-2-Amino-3-methyl-butyryl)-piperidin-3-yl]-methyl-carbamic acid tert-butyl ester

[4-(tert-Butoxycarbonyl-ethyl-amino)-piperidin-1-yl]-acetic acid

(1R,4R)-[4-(tert-Butoxycarbonyl-ethyl-amino)-cyclohexylamino]-acetic acid

[3-(tert-Butoxycarbonyl-isopropyl-amino)-piperidin-1-yl]-acetic acid

[(S)-3-(tert-Butoxycarbonyl-isopropyl-amino)-piperidin-1-yl]-acetic acid

[3-(tert-Butoxycarbonyl-cyclopropyl-amino)-piperidin-1-yl]-acetic acid

(1R,4R)-[4-(tert-Butoxycarbonyl-cyclopropyl-amino)-cyclohexylamino]-acetic acid

[1-(2-Hydroxy-ethyl)-piperidin-4-yl]-carbamic acid benzyl ester

[1-(2-Hydroxy-ethyl)-piperidin-4-ylmethyl]-carbamic acid benzyl ester

[1-(2-Hydroxy-ethyl)-pyrrolidin-3-ylmethyl]-methyl-carbamic acid benzyl ester

[2-(2-Hydroxy-ethylamino)-cyclohexyl]-methyl-carbamic acid benzyl ester