methyl (2S)-amino(phenyl)acetate

methyl N-trityl-(S)-phenylglycinate

(S)-methyl 2-oxo-3-phenyl-3-(tritylamino)propanoate

(1S)-1,4-diphenyl-1-(tritylamino)but-3-en-2-one

(S)-dimethyl (2-oxo-3-phenyl-3-(tritylamino)propyl)phosphonate