Uracil and adenine nucleosides having a 2′,3′-bromovinyl structure: highly versatile synthons for the synthesis of 2′-C- and 3′-C-Branched 2′,3′-Unsaturated Derivatives
Preparation of 2′- and 3′-bromo derivatives of 2′,3′-unsaturated uracil and adenine nucleosides has been carried out starting from the corresponding β-hydroxyselenides by way of bromination and successive selenoxide elimination. These compounds have been shown to serve as versatile synthons for the preparation of anti-HIV candidates, 2′-C- and 3′-C-branched 2′,3′-unsaturated nucleosides, through palladium-catalyzed