Asymmetric Synthesis of (−)-6′-β-Fluoro-aristeromycin via Stereoselective Electrophilic Fluorination

(−)-6′-β-Fluoro-aristeromycin (2), a potent inhibitor of S-adenosylhomocysteine (AdoHcy) hydrolase, has been synthesized via stereoselective electrophilic fluorination followed by a purine base build-up approach. Interestingly, purine base condensation using a cyclic sulfate resulted in a synthesis of (+)-5′-β-fluoro-isoaristeromycin (2a). Computational analysis indicates that the fluorine atom controlled the regioselectivity of the purine base substitution.