Mitsunobu Coupling of Nucleobases and Alcohols: An Efficient, Practical Synthesis for Novel Nonsugar Carbon Nucleosides

A simple facile synthesis of substituted purine derivatives
has been developed by using Mitsunobu conditions for an
alcohol and a respective nucleobase. A wide range of
alcohols produces good to excellent yield (>90%). The
resulting purine analogues show good regioselectivity with
N-9 substitution as the dominant products in most of the
cases. Application of diastereospecific alcohols reveals a
complete inversion of the carbon stereogenic center giving
a single diastereomer. More than two dozen novel nucleobase
derivatives have been prepared in high yield.