Two short synthetic routes to the biosynthetic purine precursor 5-aminoimid
azole ribonucleotide (AIR) based on catalytic reduction of 5-nitroimidazole
s are described. The synthetic ribonucleoside AIRs, which is also available
via one of these routes, is a convenient intermediate for the synthesis of
nucleoside analogues acid preparations of the novel "pyridine-stretched''
analogues of adenosine and inosine are described.