3-{[(tert-butoxy)carbonyl](3-methylbutan-2-yl)amino}propanoic acid

3-{[(tert-butoxy)carbonyl][(2-methoxyphenyl)methyl]amino}propanoic acid

3-{[(tert-butoxy)carbonyl][2-(4-fluorophenyl)ethyl]amino}propanoic acid

3-{[(tert-butoxy)carbonyl][(4-methoxyphenyl)methyl]amino}propanoic acid

tert-butyl 3-[(1-methoxypropan-2-yl)amino]propanoate

tert-butyl 3-{[2-(pyrrolidin-1-yl)ethyl]amino}propanoate

tert-butyl 3-[(3-methylbutyl)amino]propanoate

tert-butyl 3-[(2,2-dimethoxyethyl)amino]propanoate

tert-butyl 3-[(3-ethoxypropyl)amino]propanoate

tert-butyl 3-{[(thiophen-2-yl)methyl]amino}propanoate

ethyl 3-[(2-methylpropyl)amino]propanoate

tert-butyl 3-(cycloheptylamino)propanoate

ethyl 3-{[2-(piperidin-1-yl)ethyl]amino}propanoate

ethyl 3-(cyclopropylamino)propanoate

ethyl 3-[(3-ethoxypropyl)amino]propanoate