Hypoxanthine nucleoside counterparts of the antibiotic, cordycepin

Analogues of 3'-deoxyinosine, although of potential RNA antiviral interest, are virtually unknown. This paper reports on approaches to the synthesis of base-modified hypoxanthine 3'-deoxynucleosides. All of the target compounds are new and contain functionality at the 2-position that can be further elaborated for the synthesis of a variety of other novel analogues of 3'-deoxyinosine. Intact natural guanosine was used as the precursor and the key transformations utilized were regioselective bis- silylation thermal radical deoxygenation, regiospecific radical halogenation, metal-mediated functionalization, and selective ozonolysis. The synthetic approaches described have considerable generality in terms of entry to novel analogues of 3'-deoxyinosine. fa]1.Presented in part at the 9th International Round Table conference on Nucleosides, Nucleotides and Their Biological Applications, Uppsala, Sweden,1990.