Use of a 1- hydrorybenzotriazole activated pbospborylating reagent towards the synthesis of short RNA fragments in solution

Abstract

Evidence will be presented to show that the reagents 3a-c (X=0) obtained by the reaction of 2-chlorophenylphosphorodichloridate with 1- hydroxybenzotri-azole or l-hydroxy-6-trifluoromethyl(6-nitro)benzotriazoles, respectively, do not give, under normal coupling conditions, phosphorylation of the lactam functions in uracil or guanine. Reagent 3b (X=0) proved to be very convenient for the in situ formation of 3′–5′-phosphotriester linkages. The latter will be illustrated by the synthesis of several RNA fragments.