Practical synthesis of 9-(2,3-dideoxy-2-fluoro-β- d - threo -pentofuranosyl)adenine (FddA) via a purine 3′-deoxynucleoside

Synthesis of fluorinated nucleosides

Two practical synthetic approaches to the production of lodenosine [FddA, 9-(2,3-dideoxy-2-fluoro-beta-D-threo-pentofuranosyl)adenine] via 6-chloropurine riboside or 6-chloropurine 3'-deoxyriboside are described. The reaction sequence contains new fluorination methods and new applications of radical reduction. The reagents and reaction conditions of each step have been carefully selected to ensure robustness and safety.

Synthesis of 6-arylthio analogs of 2',3'-dideoxy-3'-fluoroguanosine and their effect against hepatitis B virus replication

A key compound, 2-amino-6-chlor-9-(2,3-dideoxy-3-fluoro-beta-D-erythro-pentofuranosyl)puine, was prepared from 2-amino-6-chloropurine riboside in 5 steps, then subjected to the nucleophilic displacement with benzenethiols to afford 6-arylthio congeners. These compounds showed a similar anti-HBV effect to that of 2',3' dideoxy-3'-fluoroguanosine.

Convenient synthesis of fluorinated nucleosides with perfluoroalkanesulfonyl fluorides

Perfluoroalkanesulfonyl fluorides are effective dehydroxy-fluorination agents for the hydroxyl group at the sugar moiety of nucleoside derivatives and give the corresponding fluorinated nucleosides in good yield with an inversion of configuration in a single step.