The N-amination of 4-(2-pyridylthio)piperidine (I) with hydroxylamine O-sulfonic acid afforded hydrazine (II). This was condensed with dichloropurine derivative (III) to yield the piperidinyl adenosine (IV). Deacetylation of (IV) by treatment with methanolic ammonia gave (V). Finally, the primary hydroxyl group of (V) was converted to the title chloride by reaction with SOCl2 in the presence of pyridine.