1-[2,5-di-O-(tert-butyldimethylsilyl)-3-C-(ethoxycarbonylethyl)-β-D-ribo-pentofuranosyl]cytosine

(2R,3R,4R,5R)-4-(tert-Butyl-dimethyl-silanyloxy)-2-(tert-butyl-dimethyl-silanyloxymethyl)-5-(2,4-dioxo-3,4-dihydro-2H-pyrimidin-1-yl)-3-hydroxy-tetrahydro-furan-3-carbaldehyde

1-[2,5-di-O-(tert-butyldimethylsilyl)-3-C-(methoxycarbonyl)-β-D-ribo-pentofuranosyl]uracil

1-[2,5-di-O-(tert-butyldimethylsilyl)-3-C-(methoxycarbonylmethyl)-β-D-ribo-pentofuranosyl]uracil

1-[2,5-di-O-(tert-butyldimethylsilyl)-3-C-(N-methylcarbamoylmethyl)-β-D-ribo-pentofuranosyl]uracil