Asymmetric Synthesis and Antiviral Activity of Novel Carbocyclic Nucleosides

With the aim to expand the repertoire of these bioactive nucleosides, we are currently exploring the antiviral properties of novel cyclohexenyl nucleosides 2 and ent-2, lacking the OH group at C5' position and therefore being conceived as chain terminators. Herein, the asymmetric synthesis of 2 and ent-2 (B = Pu or Py) starting from achiral cyclohexanone is reported (Figure 2). Main attention has been devoted to the key Tsuji-Trost rearrangement step of 3 and ent-3, whose unprecedented stereoconvergent outcome has been studied by chemical methods, as well as, by spectroscopic and in silico analysis.