Patent ID: 7339054

Claim:
A process for preparing a compound of structural formula I: wherein R 1 is C 1-6 alkyl and B is a purine or pyrimidine nucleobase selected from the group consisting of cytosine, uracil, thymine, hypoxanthine, adenine, guanine, 7-deazaguanine, 7-deazaadenine, 7-deaza-2,6-diaminopurine, and 7-deazahypoxanthine; comprising the steps of (a) producing a compound of structural formula IV: wherein B′ is optionally protected B, by contacting a compound of structural formula II: wherein PG is a hydroxyl protecting group, with a nucleophile B′ in a suitable organic solvent; and (b) removing the hydroxyl protecting groups PG and optional protecting groups in B′.