An updated review of enantioselective syntheses and biological actions of carbanucleosides.

Carbocyclic nucleosides are nucleoside analogues where the oxygen atom of the furanose ring is replaced by a methylene group, in many cases a substituted methylene moiety, giving rise to metabolically stable nucleosides analogues that are recognized by the same enzymes that interact with canonical nucleosides. In this article, we were focused on the relevant features of the chemistry and biological properties of this family of compounds emphasizing synthetic aspects to access carbocyclic nucleosides enantioselectively and a comprehensive panorama of their biological properties. Molecular recognition outlook of enzymes of pharmacological importance are discussed. The influence of sugar conformation and puckering in modulating the biological activity and the use of carbanucleosides are illustrated. The image presents a typical nucleoside structure at the center, with six chemical compounds branching out from it, each labeled and connected by arrows. These compounds are variations or derivatives of the nucleoside, including carbanucleosides bearing a sulfur atom in the sugar ring, abacavir, neplanocin C, deazaneplanocin A, and a dopamine uptake inhibitor. Each compound is shown with its molecular structure, highlighting differences in the sugar ring or attached groups relative to the typical nucleoside.