Regio- and stereoselective synthesis of 2′-β-substituted-fluoroneplanocin A analogues as potential anticancer agents

A series of 2′-β-substituted-6′-fluoro-cyclopentenyl-pyrimidines and -purines 8 and 9 were successfully synthesized from D-ribose in a regio- and stereoselective manner. The functionalization at the C2-position of 6′-fluoro-cyclopentenyl nucleosides was achieved via regioselective protection of a hydroxyl group at the C3-position and stereoselective formation of C2-triflate followed by direct S_N2 reaction with a fluoro or azido nucleophile. All the synthesized compounds were evaluated for their anticancer activities in several tumor cell lines, but were found to be neither active nor toxic.