Unsaturated fluoro-ketopyranosyl nucleosides: Synthesis and biological evaluation of 3-fluoro-4-keto-β-d-glucopyranosyl derivatives of N4-benzoyl cytosine and N6-benzoyl adenine

The protected β-nucleosides 1-(2,4,6-tri-O-acetyl-3-deoxy-3-fluoro-β-d-glucopyranosyl)-N4-benzoyl cytosine (2a) and 9-(2,4,6-tri-O-acetyl-3-deoxy-3-fluoro-β-d-glucopyranosyl)-N6-benzoyl adenine (2b), were synthesized by the coupling of peracetylated 3-deoxy-3-fluoro-d-glucopyranose (1) with silylated N4-benzoyl cytosine and N6-benzoyl adenine, respectively. The nucleosides were deacetylated and several subsequent protection and deprotection steps afforded the partially acetylated nucleosides of cytosine 7a and adenine 7b, respectively. Finally, direct oxidation of the free hydroxyl group at 4′-position of 7a and 7b, and simultaneous elimination reaction of the β-acetoxyl group, afforded the desired unsaturated 3-fluoro-4-keto-β-d-glucopyranosyl derivatives. These newly synthesized compounds were evaluated for their potential antitumor and antiviral activities. Compared to 5FU, the newly synthesized derivatives showed to be more efficient as antitumor growth inhibitors and they exhibited direct antiviral effect toward rotavirus.

Graphical abstractWe report the synthesis of three novel unsaturated fluoro-ketopyranosyl nucleosides (compounds 8a, 8b and 9a). Compared to 5FU, the newly synthesized derivates showed to be more efficient as antitumor growth inhibitors and they exhibited direct antiviral effect toward rotavirus.Figure optionsDownload full-size imageDownload as PowerPoint slide