A Convenient Method for the Synthesis of Adenylyl-(2′–5′)-adenylyl(2′–5′)-adenosine Using 3′-O-Benzoyladenosine Derivatives

N 6,3′-O-Dibenzoyladenosine was prepared by treating 2′,3′-O-(dibutylstannylene)-N6-benzoyladenosine with benzoyl chloride in methanol. The trimeric adenylyl-(2′–5′)-adenylyl-(2′–5′)-adenosine was synthesized in a good yield using N6,3′-O-dibenzoyladenosine as the starting material via the phosphotriester approach.