(2R,3R)-3-Benzyloxycarbonylamino-2-tert-butoxycarbonylamino-butyric acid

tert-butyl (3-hydroxy-1-oxo-1-(1-oxo-2,5-diazaspiro[3.4]octan-5-yl)butan-2-yl)carbamate

(S)-3-t-butoxycarbonyl-4<(S)-1-hydroxyethyl>-2,2-dimethyl-1,3-oxazolidine

Boc-D-Thr(Ms)-OMe