5'-O-[Bis(4-methoxyphenyl)phenylmethyl]-5-[7-[[6-[[5-[[2-[bis[2-[(2,2,2-trifluoroacetyl)amino]ethyl]amino]ethyl]amino]-9,10-dihydro-9,10-dioxo-1-anthracenyl]amino]hexyl]amino]-7-oxo-1-heptyn-1-yl]-2'-deoxyuridine

5'-O-[Bis(4-methoxyphenyl)phenylmethyl]-4'-C-[(1,3-dihydro-1,3-dioxo-2H-isoindol-2-yl)methyl]-2'-O-methyluridine

5'-O-[Bis(4-methoxyphenyl)phenylmethyl]-4'-C-(hydroxymethyl)-2'-O-methyluridine

4'-C-[[Bis(4-methoxyphenyl)phenylmethoxy]methyl]-5'-O-[bis(4-methoxyphenyl)phenylmethyl]-2'-O-methyluridine

4'-C-[[Bis(4-methoxyphenyl)phenylmethoxy]methyl]-5'-O-[bis(4-methoxyphenyl)phenylmethyl]-3'-O-[(1,1-dimethylethyl)dimethylsilyl]-2'-O-methyluridine

4'-C-(Hydroxymethyl)-2'-O-methyluridine

4'-C-[[Bis(4-methoxyphenyl)phenylmethoxy]methyl]-2'-O-methyluridine

4'-C-[[Bis(4-methoxyphenyl)phenylmethoxy]methyl]-3'-O-[(1,1-dimethylethyl)dimethylsilyl]-2'-O-methyluridine

5'-O-(Carboxyphosphonomethyl)-5-methyluridine

5'-O-(Carboxyphosphonomethyl)-2'-deoxyuridine

5'-O-[Bis(4-methoxyphenyl)phenylmethyl]-2'-O-[(1,1-dimethylethyl)dimethylsilyl]-4'-C-methyluridine

3'-O-[(1,1-Dimethylethyl)dimethylsilyl]-4'-C-(hydroxymethyl)-2'-O-methyluridine

N-[Bis(4-methoxyphenyl)phenylmethyl]-2'-O-[(1,1-dimethylethyl)dimethylsilyl]-3'-O-methyladenosine

(2'R)-4'-C-[[Bis(4-methoxyphenyl)phenylmethoxy]methyl]-2'-deoxy-3'-O-[(1,1-dimethylethyl)dimethylsilyl]-5'-O-[(1,1-dimethylethyl)diphenylsilyl]-2'-fluoro-2'-methyluridine

(2'R)-2'-Deoxy-3'-O-[(1,1-dimethylethyl)dimethylsilyl]-5'-O-[(1,1-dimethylethyl)diphenylsilyl]-2'-fluoro-4'-C-(hydroxymethyl)-2'-methyluridine

5'-O-[(1,1-Dimethylethyl)diphenylsilyl]-2'-O-[(2R)-2-methoxypropyl]-5-methyluridine

2'-O-[2-[Bis(2-methoxyethyl)amino]ethyl]-5'-O-[(1,1-dimethylethyl)diphenylsilyl]-5-methyluridine

5'-O-[(1,1-Dimethylethyl)diphenylsilyl]-2'-O-[(2S)-2-methoxypropyl]-5-methyluridine

5'-O-[(1,1-Dimethylethyl)diphenylsilyl]-2'-O-[(1R)-2-methoxy-1-methylethyl]-5-methyluridine

5'-O-[(1,1-Dimethylethyl)diphenylsilyl]-2'-O-[2-methoxy-1-(methoxymethyl)ethyl]-5-methyluridine