Neoglycopeptides and Neoglycoproteins

The linear assembly of glycosylated amino acids in particular usually provides well-defined products following this approach, the required carbohydrate structure is attached to an amino acid residue, typically serine and threonine for O-linked glycopeptides and asparagine for N-linked glycopeptides (Fig. I).16 

The second is a convergent approach that relies on the formation of the link late in the synthesis, once the protein scaffold for its presentation is in place. In this case, site-selective glycosylation must be in order to have chemically defined structures.17 

Although the resulting linkages do not precisely replicate natural connections, the simplified procedures allow rapid, convenient access to a wide array of neoglycopeptides that have been shown by some researchers to maintain their native biological activity.20 

Changes in glycosylation are often a hallmark of disease states.21 The structures of glycans, which decorate all eukaryotic-cell surfaces, change, for example, with the onset of cancer22 and inflammation.23 Synthetic mimics of the complex glycocopeptides and glycoproteins found on cell surfaces can modulate 

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