L-Leucine, N-phosphono-, 1-ethyl ester, cyclic (P→3',5')-ester with 2'-C-methylcytidine

L-Alanine, N-phosphono-, 1-(2-ethylbutyl) ester, cyclic (P→3',5')-ester with 2'-C-methylcytidine

L-Alanine, N-phosphono-, 1-(3-methoxypropyl) ester, cyclic (P→3',5')-ester with 2'-C-methylcytidine

L-Alanine, N-phosphono-, 1-(3-methylbutyl) ester, cyclic (P→3',5')-ester with 2'-C-methylcytidine

L-Alanine, N-phosphono-, 1-cyclohexyl ester, cyclic (P→3',5')-ester with 2'-C-methylcytidine

L-Alanine, N-phosphono-, 1-cyclopentyl ester, cyclic (P→3',5')-ester with 2'-C-methylcytidine

L-Alanine, N-phosphono-, 1-heptyl ester, cyclic (P→3',5')-ester with N-[[3-(dimethylamino)propoxy]carbonyl]-2'-C-methylcytidine

L-Alanine, N-phosphono-, 1-(3-cyclohexylpropyl) ester, cyclic (P→3',5')-ester with 2'-C-methylcytidine

L-Alanine, N-phosphono-, 1-cycloheptyl ester, cyclic (P→3',5')-ester with 2'-C-methylcytidine

L-Alanine, N-phosphono-, 1-[2-(hexyloxy)ethyl] ester, cyclic (P→3',5')-ester with 2'-C-methylcytidine

L-Alanine, N-phosphono-, 1-(2-propylpentyl) ester, cyclic (P→3',5')-ester with 2'-C-methylcytidine

L-Alanine, N-[P(S)]-phosphono-, 1-butyl ester, cyclic (P→3',5')-ester with 2'-C-methylcytidine

L-Alanine, N-[P(R)]-phosphono-, 1-heptyl ester, cyclic (P→3',5')-ester with 2'-C-methylcytidine

L-Alanine, N-[P(S)]-phosphono-, 1-heptyl ester, cyclic (P→3',5')-ester with 2'-C-methylcytidine

L-Alanine, N-[P(R)]-phosphono-, 1-butyl ester, cyclic (P→3',5')-ester with 2'-C-methylcytidine

L-Alanine, N-[P(S)]-phosphono-, 1-ethyl ester, cyclic (P→3',5')-ester with 2'-C-methylcytidine

1-[(5R,6S,8R,9R)-4-Amino-9-[[(1,1-dimethylethyl)dimethylsilyl]oxy]-1-methyl-2,2-dioxido-3-phenyl-6-[(phenylmethoxy)methyl]-7-oxa-2-thia-1-azaspiro[4.4]non-3-en-8-yl]-3,5-dimethyl-2,4(1H,3H)-pyrimidinedione

1-[(5R,6S,8R,9R)-4-Amino-9-[[(1,1-dimethylethyl)dimethylsilyl]oxy]-6-[[[(1,1-dimethylethyl)dimethylsilyl]oxy]methyl]-2,2-dioxido-3-phenyl-7-oxa-2-thia-1-azaspiro[4.4]non-3-en-8-yl]-3-ethyl-5-methyl-2,4(1H,3H)-pyrimidinedione

1-[(5R,6S,8R,9R)-4-Amino-9-[[(1,1-dimethylethyl)dimethylsilyl]oxy]-6-[[[(1,1-dimethylethyl)dimethylsilyl]oxy]methyl]-2,2-dioxido-3-phenyl-7-oxa-2-thia-1-azaspiro[4.4]non-3-en-8-yl]-3,5-dimethyl-2,4(1H,3H)-pyrimidinedione

1-[(5R,6S,8R,9R)-4-Amino-9-[[(1,1-dimethylethyl)dimethylsilyl]oxy]-6-(hydroxymethyl)-2,2-dioxido-3-phenyl-7-oxa-2-thia-1-azaspiro[4.4]non-3-en-8-yl]-5-methyl-2,4(1H,3H)-pyrimidinedione