(4R,5R)-4-(tert-Butyl-diphenyl-silanyloxymethyl)-2,2-dimethyl-5-((R)-1-methyl-3-oxo-propyl)-oxazolidine-3-carboxylic acid tert-butyl ester

(4R,5R)-4-(tert-Butyl-diphenyl-silanyloxymethyl)-2,2-dimethyl-5-((S)-1-methyl-3-oxo-propyl)-oxazolidine-3-carboxylic acid tert-butyl ester

(4R,5R)-4-(tert-Butyl-diphenyl-silanyloxymethyl)-2,2-dimethyl-5-((Z)-(R)-1-methyl-pent-3-enyl)-oxazolidine-3-carboxylic acid tert-butyl ester

(4R,5R)-4-(tert-Butyl-diphenyl-silanyloxymethyl)-2,2-dimethyl-5-((E)-(R)-1-methyl-pent-3-enyl)-oxazolidine-3-carboxylic acid tert-butyl ester

(4R,5S)-5-benzyloxymethyl-3-N-tert-butoxycarbonyl-4-hydroxymethyl-2,2-dimethyl-1,3-oxazolidine