(1S)-1-[(3aR,4R,6R,6aR)-6-{4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl}-2,2,6a-trimethyl-tetrahydro-2H-furo[3,4-d][1,3]dioxol-4-yl]ethan-1-ol

(2R,3R,4R,5R)-2-{4-amino-7H-pyrrolo[2,3-d]pyrimidin-7-yl}-5-[(1S)-1-hydroxyethyl]-3-methyloxolane-3,4-diol

2'-Azido-2',3'-dideoxy-3'-methyleneuridine

6-Chloro-9-(2-deoxy-b-L-erythro-pentofuranosyl)-9H-purin-2-amine

2',5'-C-dimethylGuanosine

3'-(Azidomethyl)-2',3'-didehydro-2',3'-dideoxyuridine

2-Thiouracil

2'-Deoxy-5-[(trifluoromethyl)seleno]uridine

3'-Azido-2',3'-dideoxy-5-methoxy-2-thiouridine

2'-azido-2',3'-dideoxy-5-methyl-3'-methyleneuridine

3'-Chloro-2',3'-dideoxy-5-[(trifluoromethyl)thio]uridine

2'-deoxy-4-thio-5-[(trifluoromethyl)thio]uridine

1-(3-Azido-2,3,6-trideoxy-α-L-lyxo-hexofuranosyl)-5-methyl-2,4(1H,3H)-pyrimidinedione

2-Amino-2-deoxy-β-D-galactopyranose

1-(3-Azido-2,3-dideoxy-α-L-lyxo-hexofuranosyl)-5-methyl-2,4(1H,3H)-pyrimidinedione

5'-Deoxy-5'-(formylamino)-2-(1-hexynyl)-Adenosine

5'-Chloro-5'-deoxy-2-(1-hexynyl)-Adenosine

N-(2-Amino-3,8-dimethylimidazo[4,5-f]quinoxalin-5-yl) 2'-deoxyguanosine

5'-(Acetylamino)-5'-deoxy-2-(1-hexynyl)-Adenosine

5'-Deoxy-2-(1-hexynyl)-5'-[(methylsulfonyl)amino]-Adenosine