合成路线1

2) The reaction of the previously described (R)-2-(2-tetrahydropyranyloxy)-1-propanol (III) with benzyl bromide (XI) by means of NaH in DMF, followed by a treatment with Dowex 50X, gives 1-benzyloxy-2(R)-propanol (XII), which is condensed with tosyloxymethylphosphonic acid diisopropyl ester (IX) by means of NaH in THF, yielding 2-benzyloxy-1(R)-methylethoxymethylphosphonic acid diisopropyl ester (XIII). The hydrogenolysis of (XIII) over Pd/C in methanol affords 2-hydroxy-1(R)-methylethoxymethylphosphonic acid diisopropyl ester (XIV), which is tosylated with tosyl chloride/dimethyl-aminopyridine in pyridine to give the expected tosylate (XV). The condensation of (XV) with adenine (VI) by means of Cs2CO3 in hot DMF yields 9-[2(R)-(diisopropoxyphosphorylmethoxy)propyl]adenine (X), which is finally hydrolyzed as before.