1-[(2R,4S,5S)-4-Allyl-5-(tert-butyl-dimethyl-silanyloxymethyl)-tetrahydro-furan-2-yl]-5-methyl-3-(2-trimethylsilanyl-ethoxymethyl)-1H-pyrimidine-2,4-dione

(2R,3S,5R)-2-(4-((2S,3R,5R)-2-(hydroxymethyl)-5-(5-methyl-2,4-dioxo-3-((2-(trimethylsilyl)ethoxy)methyl)-3,4-dihydropyrimidin-1(2H)-yl)tetrahydrofuran-3-yl)-3-oxobutyl)-5-(5-methyl-2,4-dioxo-3,4-dihydropyrimidin-1(2H)-yl)tetrahydrofuran-3-yl acetate

{(2S,3R,5R)-2-(tert-Butyl-dimethyl-silanyloxymethyl)-5-[5-methyl-2,4-dioxo-3-(2-trimethylsilanyl-ethoxymethyl)-3,4-dihydro-2H-pyrimidin-1-yl]-tetrahydro-furan-3-yl}-acetic acid

3'-O-Acetyl-5'-{3-[(3'R)-5'-(4,4'-dimethoxytrityl)-3'-deoxythymidin-3'-yl]-2-oxopropyl}-5'-deoxythymidine

{(2S,3R,5R)-2-(tert-Butyl-dimethyl-silanyloxymethyl)-5-[5-methyl-2,4-dioxo-3-(2-trimethylsilanyl-ethoxymethyl)-3,4-dihydro-2H-pyrimidin-1-yl]-tetrahydro-furan-3-yl}-acetaldehyde