The synthesis of purines and purine nucleosides continue to attract medicinal interest 1 due to their antimicrobial properties 2 and their interaction with adenosine receptors. 3 The double condensation of 4,5-diaminopyrimidines with one-carbon electrophiles (Traube synthesis) and related methods 4 remain by far the most important routes for the construction of purines, although closure of the imidazole ring to give C(8)-substituted derivatives is generally more difficult ...
