5'-O-(tert-butyldimethylsilyl)-N2-isobutyryl-3'-tritylamino-2',3'-dideoxyguanosine

Diphenyl-carbamic acid 9-[(2R,4S,5S)-5-hydroxymethyl-4-(trityl-amino)-tetrahydro-furan-2-yl]-2-isobutyrylamino-9H-purin-6-yl ester

Diphenyl-carbamic acid 9-[(2R,4S,5S)-5-(tert-butyl-dimethyl-silanyloxymethyl)-4-(trityl-amino)-tetrahydro-furan-2-yl]-2-isobutyrylamino-9H-purin-6-yl ester

N-{9-[(2R,4S,5S)-4-Amino-5-(tert-butyl-dimethyl-silanyloxymethyl)-tetrahydro-furan-2-yl]-6-oxo-6,9-dihydro-1H-purin-2-yl}-isobutyramide

N2-isobutyryl-3'-S-benzoyl-2',3'-dideoxy-3'-thioguanosine