3-{[(tert-butoxy)carbonyl](2,2-dimethoxyethyl)amino}propanoic acid

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

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

tert-butyl 3-(pentylamino)propanoate

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

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

tert-butyl 3-{[(4-methylphenyl)methyl]amino}propanoate

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

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

ethyl 3-[(prop-2-en-1-yl)amino]propanoate

ethyl 3-{[(2-methoxyphenyl)methyl]amino}propanoate