Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-2′-deoxy-3′-O-[(1R,1′S,3′aS)-2,3,3′a,4′,5′,6′-hexahydrospiro[1H-indene-1,3′-[1H,3H]pyrrolo[1,2-c][1,3,2]oxazaphosphol]-1′-yl]-N-(2-methyl-1-oxopropyl)-

Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-2′-deoxy-3′-O-[(3′aS)-1,3,3′a,4′,5′,6′-hexahydrospiro[2H-indene-2,3′-[1H,3H]pyrrolo[1,2-c][1,3,2]oxazaphosphol]-1′-yl]-N-(2-methyl-1-oxopropyl)-

Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-3′-O-[(2R,4S)-4-cyclohexyl-3-methyl-1-oxa-3-aza-2-phosphaspiro[4.4]non-2-yl]-2′-deoxy-N-(2-methyl-1-oxopropyl)-

Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-3′-O-[(2S,4S)-4-cyclohexyl-3-methyl-1-oxa-3-aza-2-phosphaspiro[4.4]non-2-yl]-2′-deoxy-N-(2-methyl-1-oxopropyl)-

Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-2′-deoxy-3′-O-[(1S,3aS)-3,3-diethyltetrahydro-1H,3H-pyrrolo[1,2-c][1,3,2]oxazaphosphol-1-yl]-N-(2-methyl-1-oxopropyl)-

Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-2′-deoxy-N-(2-methyl-1-oxopropyl)-3′-O-(2′S,5′S)-spiro[cyclopentane-1,4′-[3]oxa[1]aza[2]phosphabicyclo[3.2.0]hept]-2′-yl-

Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-2′-deoxy-N-(2-methyl-1-oxopropyl)-3′-O-[(1′R,3′aS)-tetrahydrospiro[cyclopentane-1,3′(3′aH)-[1H][1,3,2]oxazaphospholo[3,4-a]pyridin]-1′-yl]-

Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-2′-deoxy-N-(2-methyl-1-oxopropyl)-3′-O-[(1′S,3′aS)-tetrahydrospiro[cyclopentane-1,3′(3′aH)-[1H][1,3,2]oxazaphospholo[3,4-a]pyridin]-1′-yl]-

Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-3′-O-[(2S,3aS,7aS)-7a-cyclohexylhexahydro-3-methyl-1,3,2-benzoxazaphosphol-2(3H)-yl]-2′-deoxy-N-(2-methyl-1-oxopropyl)-

Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-3′-O-[(2R,3aS,7aS)-7a-cyclohexylhexahydro-3-methyl-1,3,2-benzoxazaphosphol-2(3H)-yl]-2′-deoxy-N-(2-methyl-1-oxopropyl)-

Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-2′-deoxy-N-(2-methyl-1-oxopropyl)-3′-O-[(1′S,3′aS)-tetrahydrospiro[cyclohexane-1,3′-[1H,3H]pyrrolo[1,2-c][1,3,2]oxazaphosphol]-1′-yl]-

Cytidine, N-acetyl-5′-O-[bis(4-methoxyphenyl)phenylmethyl]-2′-deoxy-3′-O-[(1′S,3′aS)-tetrahydrospiro[cyclopentane-1,3′-[1H,3H]pyrrolo[1,2-c][1,3,2]oxazaphosphol]-1′-yl]-

Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-2′-deoxy-N-(2-methyl-1-oxopropyl)-3′-O-[(1′R,3′aR)-tetrahydrospiro[cyclopentane-1,3′-[1H,3H]pyrrolo[1,2-c][1,3,2]oxazaphosphol]-1′-yl]-

Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-2′-deoxy-N-(2-methyl-1-oxopropyl)-3′-O-[(1′S,3′aS)-tetrahydrospiro[cyclopentane-1,3′-[1H,3H]pyrrolo[1,2-c][1,3,2]oxazaphosphol]-1′-yl]-

Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-2′-deoxy-N-(2-methyl-1-oxopropyl)-3′-O-[(1′S,3′aS)-tetrahydrospiro[cyclopropane-1,3′-[1H,3H]pyrrolo[1,2-c][1,3,2]oxazaphosphol]-1′-yl]-

Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-2′-deoxy-N-(2-methyl-1-oxopropyl)-3′-O-[(1S,3S,3aS)-tetrahydro-3-methyl-3-(1-methylethyl)-1H,3H-pyrrolo[1,2-c][1,3,2]oxazaphosphol-1-yl]-

Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-2′-deoxy-N-(2-methyl-1-oxopropyl)-3′-O-[(1S,3R,3aS)-tetrahydro-3-methyl-3-(1-methylethyl)-1H,3H-pyrrolo[1,2-c][1,3,2]oxazaphosphol-1-yl]-

Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-2′-deoxy-3′-O-[(1S,3S,4aS)-hexahydro-3-phenyl-1H-pyrrolo[1,2-c][1,3,2]oxazaphosphor-1-yl]-N-(2-methyl-1-oxopropyl)-

Cytidine, 5′-O-[bis(4-methoxyphenyl)phenylmethyl]-2′-deoxy-3′-O-[(1R,3S,4aS)-hexahydro-3-phenyl-1H-pyrrolo[1,2-c][1,3,2]oxazaphosphor-1-yl]-N-(2-methyl-1-oxopropyl)-

Adenosine, N-benzoyl-5′-O-[bis(4-methoxyphenyl)phenylmethyl]-2′-deoxy-3′-O-[(3S,3aS)-tetrahydro-3-[(1-methylsilacyclohex-1-yl)methyl]-1H,3H-pyrrolo[1,2-c][1,3,2]oxazaphosphol-1-yl]-