[(R)-Cyano-((4S,5R)-2,2,4,5-tetramethyl-[1,3]dioxolan-4-yl)-methyl]-carbamic acid tert-butyl ester

(2S,3R)-2-Azido-3-(tert-butyl-dimethyl-silanyloxy)-butyric acid

(R)-2-[(2S,3R)-2-(9H-Fluoren-9-ylmethoxycarbonylamino)-3-hydroxy-butyrylamino]-3-hydroxy-propionic acid methyl ester

(R)-2-{(2S,3R)-2-[(2S,3R)-2-Azido-3-(tert-butyl-dimethyl-silanyloxy)-butyrylamino]-3-triethylsilanyloxy-thiobutyrylamino}-3-hydroxy-propionic acid methyl ester

(R)-2-{(2S,3R)-2-[(2S,3R)-2-Azido-3-(tert-butyl-dimethyl-silanyloxy)-butyrylamino]-3-triethylsilanyloxy-thiobutyrylamino}-3-triethylsilanyloxy-propionic acid methyl ester