Trifluoro-methanesulfonic acid (3aR,6S,6aR)-5-((R)-2,2-dimethyl-[1,3]dioxolan-4-yl)-2,2-dimethyl-tetrahydro-furo[2,3-d][1,3]dioxol-6-yl ester

(2S,3R,4R,5R)-3-Azido-4-(tert-butyl-dimethyl-silanyloxy)-5-(2-chloro-6-methylamino-purin-9-yl)-tetrahydro-furan-2-carboxylic acid methylamide

(2S,3R,4R,5R)-3-Amino-4-(tert-butyl-dimethyl-silanyloxy)-5-(2-chloro-6-methylamino-purin-9-yl)-tetrahydro-furan-2-carboxylic acid methylamide

(2S,3R,4R,5R)-4-(tert-Butyl-dimethyl-silanyloxy)-3-[3-(2-chloro-acetyl)-ureido]-5-(2-chloro-6-methylamino-purin-9-yl)-tetrahydro-furan-2-carboxylic acid methylamide

(2S,3S,4R,5R)-3-Azido-5-(2-chloro-6-methylamino-purin-9-yl)-4-hydroxy-tetrahydro-furan-2-carboxylic acid methylamide