Improved Method for the Solid-Phase Synthesis of Oligoribonucleotide 5′-Triphosphates

Abstract

We have developed an improved solid-phase method for the synthesis of 5′-triphosphates (5′-TPs) of oligoribonucleotides. The method is based on the use of salicyl phosphorochloridite as the phosphitylating reagent and the improvement is characterized by the use of the highly reactive pyrophosphorylating reagent tris(tetra-n-butylammonium) hydrogen pyrophosphate instead of the conventional tri-n-butylammonium salt for the nucleophilic substitution reaction to form the cyclic ester intermediate. The improved method can be used to generate oligoribonucleotide 5′-TPs efficiently and reproducibly.