5-[3-(Acetyloxy)-1-propyn-1-yl]-2-amino-3,7-dihydro-7-β-D-ribofuranosyl-4H-pyrrolo[2,3-d]pyrimidin-4-one

2-Amino-3,7-dihydro-5-[2-(4-pyridinyl)ethynyl]-7-β-D-ribofuranosyl-4H-pyrrolo[2,3-d]pyrimidin-4-one

N-[7-[5-O-[Bis(4-methoxyphenyl)phenylmethyl]-3-O-[[bis(1-methylethyl)amino](2-cyanoethoxy)phosphino]-2-deoxy-β-D-erythro-pentofuranosyl]-4,7-dihydro-4-oxo-5-[2-(4-pyridinyl)ethynyl]-3H-pyrrolo[2,3-d]pyrimidin-2-yl]-2,2-dimethylpropanamide

N-[7-[5-O-[Bis(4-methoxyphenyl)phenylmethyl]-2-deoxy-β-D-erythro-pentofuranosyl]-4,7-dihydro-4-oxo-5-[2-(4-pyridinyl)ethynyl]-3H-pyrrolo[2,3-d]pyrimidin-2-yl]-2,2-dimethylpropanamide

N-[7-[5-O-[Bis(4-methoxyphenyl)phenylmethyl]-3-O-[[bis(1-methylethyl)amino](2-cyanoethoxy)phosphino]-2-deoxy-β-D-erythro-pentofuranosyl]-4,7-dihydro-4-oxo-5-(2-phenylethynyl)-3H-pyrrolo[2,3-d]pyrimidin-2-yl]-2,2-dimethylpropanamide

N-[7-[5-O-[Bis(4-methoxyphenyl)phenylmethyl]-2-deoxy-β-D-erythro-pentofuranosyl]-4,7-dihydro-4-oxo-5-(2-phenylethynyl)-3H-pyrrolo[2,3-d]pyrimidin-2-yl]-2,2-dimethylpropanamide

N-[7-[5-O-[Bis(4-methoxyphenyl)phenylmethyl]-3-O-[[bis(1-methylethyl)amino](2-cyanoethoxy)phosphino]-2-deoxy-β-D-erythro-pentofuranosyl]-4,7-dihydro-5-iodo-4-oxo-3H-pyrrolo[2,3-d]pyrimidin-2-yl]-2,2-dimethylpropanamide

N-[7-[5-O-[Bis(4-methoxyphenyl)phenylmethyl]-2-deoxy-β-D-erythro-pentofuranosyl]-4,7-dihydro-5-iodo-4-oxo-3H-pyrrolo[2,3-d]pyrimidin-2-yl]-2,2-dimethylpropanamide

N-[7-(2-Deoxy-β-D-erythro-pentofuranosyl)-4,7-dihydro-5-iodo-4-oxo-3H-pyrrolo[2,3-d]pyrimidin-2-yl]-2,2-dimethylpropanamide

N-[7-[2-Deoxy-3,5-bis-O-(4-methylphenyl)-β-D-erythro-pentofuranosyl]-4,7-dihydro-5-iodo-4-oxo-3H-pyrrolo[2,3-d]pyrimidin-2-yl]-2,2-dimethylpropanamide

N-[4-Chloro-7-[2-deoxy-3,5-bis-O-(4-methylphenyl)-β-D-erythro-pentofuranosyl]-5-iodo-7H-pyrrolo[2,3-d]pyrimidin-2-yl]-2,2-dimethylpropanamide