tert-butyl ((S)-1-(((R)-2-((3aR,5R,6R,6aR)-6-(benzyloxy)-2,2,6-trimethyltetrahydrofuro[2,3-d][1,3]dioxol-5-yl)-2-hydroxyethyl)amino)-1-oxopropan-2-yl)carbamate

tert-butyl ((S)-2-(((R)-2-((3aR,5R,6R,6aR)-6-(benzyloxy)-2,2,6-trimethyltetrahydrofuro[2,3-d][1,3]dioxol-5-yl)-2-hydroxyethyl)amino)-2-oxo-1-phenylethyl)carbamate

tert-butyl ((R)-1-(((R)-2-((3aR,5R,6R,6aR)-6-(benzyloxy)-2,2,6-trimethyltetrahydrofuro[2,3-d][1,3]dioxol-5-yl)-2-hydroxyethyl)amino)-3-methyl-1-oxobutan-2-yl)carbamate