O-Glycopeptides synthesis

P. Schultheiss-Reimann and H. Kunz, O-Glycopeptide synthesis using 9-fluorenylmethoxycar-bonyl (Fmoc)-protected synthetic units, Angew. Chem. lnt. Ed. Engl. 22 62 (1983). 

Reimer, K., Meldal, M., Kusumoto, S., Fukase, K., and Bock, K. (1993) Small-scale solid-phase O-glycopeptide synthesis of linear and cyclized hexapeptides from blood-clotting factor IX containing 0-(a-D-Xyl-(l-3)-a-D-Xyl-(l-3)-(3-D-Glc)-L-Ser../. Am. Chem. Soc. Perkin Trans /., 925-932. 

Seitz O, Glycopeptide synthesis and the effects of glycosylation on protein structure and activity, Chembiochem, l(4) 214-46, 2000. 

Nakahara, Y, lijima, H, Ogawa, T, StereocontroUed approaches to O-glycopeptide synthesis. In Synthetic Oligosaccharides, Kovac, P, Ed., American Chemical Society, Washington DC, ACS Symp. Ser., Vol. 560, pp. 249-266, 1994. 

The Fmoc group can also be combined with the fert-butyl ester in O-glycopeptide synthesis [16,34]. The Fmoc serine and threonine tert-butyl esters with free P-hydroxyl groups are required as starting materials for this chemistry. These compounds (e.g., the threonine... 

The protocol for O-glycopeptide synthesis described below has been optimized in our labs to fulfill the requirements for our covalent microarray platform. Key features in this respect are (1) small-scale synthesis, in which only few milligrams of resin are used per peptide, in order to allow for higher throughput by parallel robotic... 

Schultheiss-Reimann P, Runz H (1983) O-glycopeptide synthesis using 9-fluorenyl methoxycarbonyl (Emoc)-protected synthetic units. Angew Chem Int Ed Eng 22 62-63... 

Scheme 2 O- and /V-S ugar Protecting Groups Used in Glycopeptide Synthesis...

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. 

O-Glycopeptides and glycoconjugates, in which the saccharide is linked to a peptide or a protein through a linear or a branched aliphatic spacer, have been used to enhance biological activity. 298 301 373,472,481-483 Peracetylated galabiose and lactose react with 3-sulfanylpropanoic acid in the presence of BF3 and the products have been used in the synthesis of HEL(46-61) and shorter fragments thereof. 164 ... 

O- and N-Glycopeptides Synthesis of Selectively Deprotected Building Bloc... 

A major progress in glycopeptide synthesis was achieved when it was demonstrated that the NH2-terminal 9-fiuorenylmethoxycarbonyl (Fmoc) group can be selectively removed from glycopeptides using the weak base morpholine (pKa 8.3). This holds true for O-glycosyl serine and threonine esters, which are sensitive to base-catalyzed P-elimination of the carbohydrate [10]. 

Glycopeptides contain many functional groups of different reactivity as well as O- and /V-glycosidic bonds. Therefore, the compatibility and chemoselectivity of the applied reactions is a fundamental prerequisite in glycopeptide synthesis. In this chapter, efficient and generally applicable methods and their combinations will be illustrated by examples [5,8,91. 

Chemoenzymatic solution- and solid-phase synthesis of O-glycopeptides of the mucin domain of MAdCAM-1. A general route to O-LacNAc, O-sialyl-LacNAc, and O-sialyl-Lewis-X peptides, J. Am. Chem. Soc., 119 (1997) 8766-8776. 

Jensen, K., Hansen, P., Venugopal, D., and Barany, G. (1996) Synthesis of 2-acetamido-2-deoxy-(3-D-glucopyranose O-glycopeptides from V-dithiasuccinoyl -protected derivatives. /. Am. Chem. Soc. 118, 3148-3155. 

Kunz, H. and Birnbach, S. (1986) Synthesis of O-glycopeptides of the tumor-associated Tn- and T-antigen type and their binding to bovine serum albumin. Agnew. Chem Int Ed. 98(4), 360-362. 

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