Biomimetic protecting-group-free 2′, 3′-selective aminoacylation of nucleosides and nucleotidesElectronic supplementary information (ESI) available: Materials and methods, synthetic procedures for unprotected acyl phosphates, analytical and spectroscopic data, chromatograms. See DOI: 10.1039/c0ob00795a

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. Efficient lanthanum-promoted aminoacylation of ribonucleosides and ribonucleotides can be achieved with an aminoacyl phosphate ester with a free amino group.