Patent ID: 7271157

Claim:
A method of preparing compounds of Formula I: wherein R is optionally substituted phenyl, comprising the steps of: a. in the presence of base, contacting (4S,2R,3R,5R)-2-(6-chloropurin-9-yl)-5-(hydroxymethyl)oxolane-3,4-diol with a protected (2-hydroxy) cyclopentylamine compound having a protecting group on the 2-hydroxy moiety; b. contacting the product of step (a) with thionyl chloride in the presence of a second base; c. contacting the product of step (b) with a third base; d. removing the protecting group from the 2-hydroxy moiety either before or after reacting the product of step (c) with a compound of the formula RSH in the presence of a fourth base.