6-benzyl-1-methylpyridin-2-one

(3R,5S)-3-benzyl-5-{(1S)-1-[(tert-butoxycarbonyl)amino]-2-phenylethyl}dihydrofuran-2-(3H)-one

tert-butyl (1S)-1-[(2S)-5-oxotetrahydrofuran-2-yl]-2-phenylethylcarbamate

(4S,5S)-4-Benzyl-5-[((S)-1-methoxycarbonyl-ethylamino)-methyl]-2,2-dimethyl-oxazolidine-3-carboxylic acid tert-butyl ester

(4S,5S)-4-Benzyl-5-[((S)-1-methoxycarbonyl-2-methyl-propylamino)-methyl]-2,2-dimethyl-oxazolidine-3-carboxylic acid tert-butyl ester