Application of a solid-phase β-triphosphitylating reagent in the synthesis of nucleoside β-triphosphates

A β-triphosphitylating reagent was subjected to reaction with aminomethyl polystyrene resin-bound p-acetoxybenzyl alcohol to yield the corresponding polymer-bound β-triphosphitylating reagent. The solid-phase reagent was reacted with unprotected nucleosides (e.g., 3′-azido-3′- deoxythymidine, cytidine, thymidine, uridine, inosine, or adenosine) in the presence of 1H-tetrazole. Polymer-bound nucleosides underwent oxidation with t-butyl hydroperoxide, deprotection of cyanoethoxy groups with DBU, and the acidic cleavage, respectively, to afford only monosubstituted 5′-O-β-triphosphorylated nucleosides.