An efficient regioselective synthesis of substituted purine analogues of guanosine and inosine

Abstract

Condensation of 2-bromo-6-(4-nitrophenylethoxy)purine as the trimethylsilyl derivative (5a) with 1,2,3,5-tetra-O-acetyl-β-D-ribofuranose, 1-O-acetyl-2,3-di-O-benzoyl-5-diethoxy-phosphinyl-β-D-ribofuranose, and (2-acetoxythoxy)methyl bromide resulted in N⁹-regioselective alkylation to give (6a–c), which were then converted to guanine and hypoxanthine nucleosides, nucleotides, and Acyclovir analogues, respectively.