2'-Deoxyadenosine (I) was protected as the diacetate (II) on treatment with acetic anhydride and a catalytic amount of dimethylaminopyridine. Then, reaction with an excess of isopentyl nitrite and diiodomethane under illumination of a tungsten lamp provided iodide (III). Subsequent treatment with ethanolic methylamine effected both deacetylation and substitution of iodide to give 2'-deoxy-N6-methyladenosine (IV). Finally, this was treated with phosphoryl chloride and Proton Sponge(R) in trimethyl phosphate at 0 C, followed by quenching with triethyl ammonium bicarbonate buffer to yield the target bisphosphate.