Synthesis of a new class of spin-labeled purine ribonucleosides and development of a novel nucleophilic reaction to form 2,6,8-trifunctionalized purine derivatives

Abstract

Novel purine ribonucleosides with a tert-butylhydroxyamino function at the C8-position of the purine nucleus were synthesized, and were oxidized to aminoxyl radicals by treatment with Ag₂O; after O-acylation of the tert-butylhydroxyamino group, nucleophilic substitution at the C2-position of the purine nucleus easily proceeded with elimination of the N-acyloxy group to provide a novel method for preparing C2-functionalized purine ribonucleosides.