Glycopeptides assembly

Most frequently, sugar O-acetates have been used in N-linked glycopeptide synthesis. The protection of the glycosylamines as O-acetates requires two steps in the deprotection procedure after glycopeptide assembly. 

Scheme 47 Glycopeptide Assembly with Triantennary Building Block 1491...

Vargas-Berenguel, A., Meldal, M., Paulsen, H., and Bock, K. (1994) Convenient synthesis of 0-(2-acetamido-2-deoxy-(3-D-glucopyranosyl)-serine and -threonine building blocks for solid-phase glycopeptide assembly. J. Am. Chem. Soc. Perkin Trans I., 2615-2619. 

Meldal M, St Hilaire PM. Synthetic methods of glycopeptide assembly, and biological analysis of glycopeptide products. Curr. Opin. Chem. Biol. 1997 1 552-563. 

The glycopeptide assembly process relies mainly on the established methods of solid-phase peptide chemistry. However, the synthetic strategy has to be adapted to accommodate the chemical sensitivities of the carbohydrate moiety, whether the saccharide is present during chain elongation or the carbohydrate moiety is incorporated after chain assembly is complete. Of the different reported strategies for the preparation of glycopeptides [12],... 

What is the physiological role — if any — of retinyl mannosyl phosphate Does it act as a mannosyl donor in glycopeptide assembly There is no simple answer as yet. It is clearly established that many cells can synthesise retinyl phosphate from retinol and, thence, can produce retinyl mannosyl phosphate, so the substance itself is clearly a physiological product. 

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