3-[5-O-[Bis(4-methoxyphenyl)phenylmethyl]-3-O-[[bis(1-methylethyl)amino](2-cyanoethoxy)phosphino]-2-O-[(1,1-dimethylethyl)dimethylsilyl]-β-D-ribofuranosyl]-3H-[1,2,4]triazolo[5,1-i]purine

3-[5-O-[Bis(4-methoxyphenyl)phenylmethyl]-3-O-[(1,1-dimethylethyl)dimethylsilyl]-β-D-ribofuranosyl]-3H-[1,2,4]triazolo[5,1-i]purine

3-[5-O-[Bis(4-methoxyphenyl)phenylmethyl]-2-O-[(1,1-dimethylethyl)dimethylsilyl]-β-D-ribofuranosyl]-3H-[1,2,4]triazolo[5,1-i]purine

3-[5-O-[Bis(4-methoxyphenyl)phenylmethyl]-β-D-ribofuranosyl]-3H-[1,2,4]triazolo[5,1-i]purine