2-Oxa-5-azabicyclo[2.2.1]heptane-5-carboxylic acid, 3-[1,6-dihydro-2-[(2-methyl-1-oxopropyl)amino]-6-oxo-9H-purin-9-yl]-7-hydroxy-1-(hydroxymethyl)-, 9H-fluoren-9-ylmethyl ester, (1R,3R,4R,7S)-

2-Oxa-5-azabicyclo[2.2.1]heptane-5-carboxylic acid, 1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-3-[6-[[(dimethylamino)carbonyl]oxy]-2-[(2-methyl-1-oxopropyl)amino]-9H-purin-9-yl]-7-[(trimethylsilyl)oxy]-, 9H-fluoren-9-ylmethyl ester, (1R,3R,4R,7S)-

2-Oxa-5-azabicyclo[2.2.1]heptane-5-carboxylic acid, 1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-3-[6-[[(dimethylamino)carbonyl]oxy]-2-[(2-methyl-1-oxopropyl)amino]-9H-purin-9-yl]-7-hydroxy-, 9H-fluoren-9-ylmethyl ester, (1R,3R,4R,7S)-

Propanamide, N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]hept-3-yl]-6,9-dihydro-6-oxo-1H-purin-2-yl]-2-methyl-

Methanimidamide, N′-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-7-[(trimethylsilyl)oxy]-2-oxa-5-azabicyclo[2.2.1]hept-3-yl]-1,2-dihydro-5-methyl-2-oxo-4-pyrimidinyl]-N,N-dimethyl-