REGIOSELECTIVE SYNTHESIS OF 9-SUBSTITUTED-8-AZAGUANINES 6-DIHYDRO-7H-1,2,3-TRIAZOLO[4,5-D]PYRIMIDIN-7-ONE)

By modifying previously described methods for the synthesis of 9-subst ituted-guanines from imidazoles, we have developed a new procedure for the regioselective synthesis of 9-substituted-8-azaguanines 6-dihydro -7H-1,2,3-triazolo[4,5-djpyrimidin-7-one) from triazoles in high yield s. The method seems suitable for the introduction of a variety of subs tituents including sugars, carbocyclic, acyclic and carboacyclic chain s.