phenylmethyl (2S,3S)-2-azido-3-hydroxy-4-methylpentanoate

benzyl (2S,3R)-Nα-(benzyloxycarbonyl)-3-isopropylaziridine-2-carboxylate

(4S,5S) 5-isopropyl-2-oxo-oxazolidine-3,4-dicarboxylic acid 4-benzyl ester 3-tert-butyl ester

(4S,5S) 5-isopropyl-2-oxo-oxazolidine-4-carboxylic acid benzyl ester

[(3S,4S)-3-((S)-1-Hydroxy-2-methyl-propyl)-1-[(S)-1-(4-methoxy-phenyl)-ethyl]-2-oxo-4-(2-oxo-2,5-dihydro-furan-3-yl)-azetidin-3-yl]-carbamic acid tert-butyl ester

[(3S,4S)-3-((S)-1-Hydroxy-2-methyl-propyl)-1-[(S)-1-(4-methoxy-phenyl)-ethyl]-2-oxo-4-(2-trimethylsilanyl-furan-3-yl)-azetidin-3-yl]-carbamic acid tert-butyl ester

(1S,4R,5S)-4-(2-Chloro-ethyl)-1-((S)-1-hydroxy-2-methyl-propyl)-2,6-diaza-bicyclo[3.2.0]heptane-3,7-dione