Coupling of 2-fluoro-3,5-di-O-benzoyl-α-D-arabinofuranosyl bromide with 4-methoxypyrazolo[3,4-d]pyrimidine gave an α-D/β-D mixture of NL and N2- coupled products. All the anomers were separated and deblocked to yield the corresponding nucleosides. The β-D-anomer 7 was converted to the 4-amino derivative 11, which was deaminated by adenosine deaminase to give the 4-oxo compound 12. Compound 7 showed significant activity against human cytomegalovirus and hepatitis B virus, and compound 11 showed activity against human herpes virus 8. All the compounds were noncytotoxic in several human tumor-cell lines in culture.