Biomimetic protecting-group-free 2', 3'-selective aminoacylation of nucleosides and nucleotides

Aminoacyl phosphate monoesters can be prepared free of an amino-protecting group and used directly in lanthanum-promoted selective monoacylation of either the 2' or 3'-hydroxyl of nucleosides and nucleotides. For example, phenylalanyl ethyl phosphate rapidly forms esters with either of the 2' or 3'-hydroxyls of ribonucleosides and nucleotides in the presence of lanthanum ions in aqueous buffer. Oligomerization of the aminoacyl phosphate is much slower than ester formation and is not a competitive process. Competing hydrolysis of the reagent is slow. By extension, this route should provide a simplified general route to synthetically aminoacylated derivatives of tRNA.