A novel method for the labelling of peptides and proteins through a bioorthogonal Staudinger reaction by using 2-cyanoethyl phosphoramidites.

Chemoselective modification of biomolecules: The reaction between 2-cyanoethyl phosphoramidites and azides is economical and can be performed in different solvents, including aqueous buffers. The course of the reaction with azido-modified amino acids, peptides or proteins and different label molecules was followed by (31)P NMR spectroscopy.

Site specific chemoselective labelling of proteins with robust and highly sensitive Ru(II) bathophenanthroline complexes.

The bioorthogonal and chemoselective fluorescence labelling of several cell-free synthesized proteins containing a site-specifically incorporated azido amino acid was possible using different alkyne-functionalized Ru(II) bathophenanthroline complexes. We were able to achieve a selective labelling even in complex mixtures of proteins despite the fact that ruthenium dyes normally show a high tendency for unspecific interactions with proteins and are commonly used for total staining of proteins. Since the employed Ru complexes are extremely robust, photo-stable and highly sensitive, the approach should be applicable to the production of labelled proteins for single molecule spectroscopy and fluorescence-based interaction studies.

NBS-DMSO as a nonaqueous nonbasic oxidation reagent for the synthesis of oligonucleotides.

A new method for the oxidation of nucleoside phosphite triester into phosphate triester under nonbasic and nonaqueous conditions using NBS-DMSO in CH(3)CN has been developed. The utility of this method for solution- and solid-phase synthesis of oligonucleotide is demonstrated.