(S)-1-[2-(2-Oxo-piperidin-1-yl)-acetyl]-pyrrolidine-2-carboxylic acid ethyl ester

1-[2-(4-Isobutyl-5-oxo-oxazolidin-3-yl)-2-oxo-ethyl]-piperidin-2-one

1-[2-((R)-4-Isobutyl-5-oxo-oxazolidin-3-yl)-2-oxo-ethyl]-piperidin-2-one

1-((bromomethyl)dimethylsilyl)-2-piperidone