IMPROVED PROCESS FOR PREPARING THE ANTIVIRAL AGENT [1S-(1 alpha , 3 alpha , 4 beta )]-2-AMINO-1,9-DIHYDRO-9-[4-HYDROXY-3-(HYDROXYMETHYL)-2-METHYLENECYCLOPENTYL]-6H-PURIN-6-ONE

摘要

Improvements in the yield of the antiviral agent of formula (I) are obtained by employing Dess-Martin periodinane to convert the cyclopentol of formula (VI) to the cyclopentanone of formula (VIII) and the methylenation of this cyclopentanone to the compound of formula (XI) by use of a Nysted reagent, Tebbe reagent, or a reagent prepared from zinc powder, diiodomethane, lead powder or lead chloride, and titanium tetrachloride in a suitable solvent.