(3E,5R,6S,7S)-8-[(tert-butyldimethylsilyl)oxy]-6,7-(isopropylidenedioxy)-5-[(2,2,2-trichloroethoxycarbonyl)amino]-oct-3-ene

(4S,5S)-4-[(S)-(tert-Butoxycarbonylamino)methoxycarbonylmethyl]-5-(tert-butyldimethylsilyloxymethyl)-2,2-dimethyl-1,3-dioxolane

methyl 2-N-[(tert-butoxycarbonyl)amino]-2-deoxy-3,4-O-isopropylidene-L-xylonate

(3E,5R,6S,7S)-5-[(tert-butoxycarbonyl)amino]-8-[(tert-butyldimethylsilyl)oxy]-6,7-(isopropylidenedioxy)-oct-3-ene

tert-Butoxycarbonylamino-((4S,5S)-5-carbamoyloxymethyl-2,2-dimethyl-[1,3]dioxolan-4-yl)-acetic acid methyl ester

{(S)-1-[(4S,5S)-5-(tert-Butyl-dimethyl-silanyloxymethyl)-2,2-dimethyl-[1,3]dioxolan-4-yl]-2-oxo-ethyl}-carbamic acid tert-butyl ester