ethyl 3-{[3-(dimethylamino)-2,2-dimethylpropyl]amino}propanoate

tert-butyl 2-methyl-3-[(4-phenylbutan-2-yl)amino]propanoate

methyl 2-methyl-3-[(pentan-3-yl)amino]propanoate

methyl 3-[(2-methylpropyl)amino]butanoate

methyl 3-[(2-phenylethyl)amino]butanoate

methyl 3-[(2-methoxyethyl)amino]butanoate

methyl 2-methyl-3-{[(pyridin-4-yl)methyl]amino}propanoate

methyl 3-{[2-(diethylamino)ethyl]amino}butanoate

methyl 3-{[2-(4-methoxyphenyl)ethyl]amino}-2-methylpropanoate

methyl 3-[(3-phenylpropyl)amino]butanoate

methyl 3-{[(4-chlorophenyl)methyl]amino}butanoate