[2(1S),4S,5S]-4,5-dicyclohexyl-2-[1-azido-2-[[(1,1-dimethylethyl)dimethylsilyl]oxy]ethyl]-1,3,2-dioxaborolane

[2(1R),4S,5S]-4,5-dicyclohexyl-2-[1-chloro-2-[[(1,1-dimethylethyl)dimethylsilyl]oxy]ethyl]-1,3,2-dioxaborolane