(4S,5R)-3-N-tert-butyloxycarbonyl-4-methoxycarbonyl-5-((1''R,3''E)-1''-methylpent-3''-enyl)-2,2-dimethyl-1,3-oxazolidine

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

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

(4R,5R)-3-N-tert-butoxycarbonyl-4-tert-butyldiphenylsilyloxymethyl-5-<3''-hydroxypropyl>-2,2-dimethyl-1,3-oxazolidine