Glycoproteins carbohydrate-protein linkages

Glycoproteins or mucoproieins. Compounds of proteins with carbohydrates. All glycoproteins contain a hexosamine and usually sulphate, ethanoate and glucuronic acid. The carbohydrate-protein linkages are, in some cases covalent and in others of the salt type. Aqueous solutions of glycoproteins are extremely viscous. 

V. Structural Analysis of Glycopeptides and Glycoproteins Containing Unusual Carbohydrate-Protein Linkages... 

A linkage involving 4-hydroxy-L-proline and L-arabinose has been detected in glycoproteins of plant origin, and it is also possible that L-cys-teine is part of a carbohydrate-protein linkage. Of the types of linkages just mentioned, which have been extensively discussed in reviews,2-9 only the first three have been the subject of synthetic studies, and it is this aspect of the work that will be discussed in the present Chapter. 

Jones, J.K.N., Perry, M.B., Shelton, B., and Walton, D.T. (1961) Carbohydrate-protein linkage in glycoproteins. I. Syntheses of some model substituted amides and a (2-amino-2-deoxy-D-glucosyl)-L-serine. Can. J. Chem. 39, 1005-1016. 

The Carbohydrate-Protein Linkage in Glycoproteins. Part I. The Syntheses of Some Model Substituted Amides and an L-Seryl-D-glucosaminide, J. K. N. Jones, M. B. Perry, B. Shelton, and D. J. Walton, Can.. Chem., 39 (1961) 1005-1016. 

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