Stereoselective Synthesis of d‑5-Homo-4-selenoribose as a Versatile Intermediate for 4′-Selenonucleosides

Stereoselective synthesis of d-5-homo-4-selenoribose, serving as a versatile intermediate for the synthesis of 4′-selenonucleosides <b>12a</b>–<b>c</b>, was accomplished using Sharpless asymmetric epoxidation, regioselective cleavage of the α,β-epoxide, and stereoselective reduction of the ketone as the key steps

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

(−)-6′-β-Fluoro-aristeromycin (<b>2</b>), a potent inhibitor of <i>S</i>-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 (<b>2a</b>). Computational analysis indicates that the fluorine atom controlled the regioselectivity of the purine base substitution