1-<5-O-(tert-butyldimethylsilyl)-2,3-dideoxy-β-L-ribofuranosyl>-5-fluorocytosine

4-amino-1-((2S,5R)-5-(((tert-butyldiphenylsilyl)oxy)methyl)tetrahydrofuran-2-yl)-5-fluoropyrimidin-2(1H)-one

5-(1-diphenylsilyloxy-2,2-dimethylpropyl)oxolan-2-one

(2R,5S)-5-(4-Acetylamino-5-fluoro-2-oxo-2H-pyrimidin-1-yl)-tetrahydro-furan-2-carboxylic acid ethyl ester

4-Amino-1-[(2S,3S,5R)-5-(tert-butyl-diphenyl-silanyloxymethyl)-3-phenylselanyl-tetrahydro-furan-2-yl]-5-fluoro-1H-pyrimidin-2-one