(4R,5S)-4-[(E)-(S)-4-Benzyloxy-1-(tert-butyl-dimethyl-silanyloxy)-but-2-enyl]-5-benzyloxymethyl-oxazolidin-2-one

methyl (2S,3a'S,6'R,7'R,7a'S)-2-methoxycarbonylamino-4[[1'-methyl-2'-oxo-7'-(triethylsilyloxy)hexahydropyrano[4,3-d]oxazol-6'-yl]methyl]pent-4-enoate

(3aS,6R,7R,7aR)-1-methyl-6-(2-oxopropyl)-7-(triethylsilyloxy)hexahydropyrano[4,3-d]oxazol-2-one

(4S,5S,1'S,E)-5-(tert-butyldimethylsilyloxy)methyl-4-[1',4-di(tert-butyldimethylsilyloxy)but-2'-enyl]-3-methyloxazolidin-2-one

methyl (2S,4R,3a'S,6'R,7'R,7a'S)-4,5-epoxy-2-methoxycarbonylamino-4-[[1'-methyl-2'-oxo-7'-(triethylsilyloxy)hexahydropyrano[4,3-d]oxazol-6'-yl]methyl]pentanoate

(3aS,6R,7R,7aR)-1-methyl-7-triethylsilyloxy-6-[(2-trifluoromethanesulfonyloxy)prop-2-enyl]hexahydropyrano[4,3-d]oxazol-2-one

(4S,5S,1'S,E)-5-(tert-butyldimethylsilyloxy)methyl-4-[4'-chloro-1'-(tert-butyldimethylsilyloxy)but-2'-enyl]-3-methyloxazolidin-2-one

(S)-4-((3aS,6R,7R,7aS)-7-Hydroxy-1-methyl-2-oxo-hexahydro-pyrano[4,3-d]oxazol-6-ylmethyl)-2-methoxycarbonylamino-pent-4-enoic acid methyl ester

(3aS,5aR,8aR,8bS)-1-aza-1-methyl-3,5,8-trioxa-as-hexahydroindacene-2,7-dione

(3a'S,6'R,7'R,7a'S)-N-methoxy-N-methyl-2-[1'-methyl-2'-oxo-7'-(triethylsilyloxy)hexahydropyrano[4,3-d]oxazol-6'-yl]acetamide