Chemoselective ligation strategy

Scheme 1 Examples of Chemoselective Ligation Strategies Resulting in the Formation of Nonpeptidic Bonds (a) Hydrazone, (b) Oxime, (c) Thiazolidine...

Strategies for functionalization have been developed that exploit the naturally occurring amino acids as well as the non-natural ones. Post-synthetic modifications have been reported that are based on reactive sites that self catalyze the incorporation of the new functionality at the side chains of Lys residues [24,25] and on the chemoselective ligation reaction [26-29]. These developments in combination with new methodology for the synthesis of large proteins [30] provide access to a highly versatile pool of new polypeptides and proteins. 

Fig. 4. Strategy for the synthesis of RAFT-derived vaccines by chemoselective ligation.

Hackenberger CPR, Schwarzer D (2008) Chemoselective ligation and modification strategies for peptides and proteins. Angew Chem Int Ed 47 10030-10074... 

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