A general synthesis of 4-substituted 1-(β-D-ribofuranosyl)imidazo[4,5-c]pyridines

Abstract

The trimethylsilyl derivative (I) of 4,6-dichloroimidazo[4,5-c]pyridine was condensed with 2,3,5-tri-O-benzoyl-D-ribofuranosyl bromide (II) to afford, after removal of protecting groups, the isomeric 1- and 3-(β-D-ribofuranosyl) derivatives [(V) and (VI)]. The reaction of the nucleoside (V) with a variety of nucleophiles afforded various 4-substituted 6-chloro-derivatives. Removal of the 6-chloro-group by catalytic hydrogenation provided a general synthesis of 4-substituted 1-(β-D-ribofuranosyl)imidazo[4,5-c]pyridines, including the 4-amino-compound (3-deaza-adenosine).