Glycopeptide amino acid

The advantages of the methoxyethyl ester over some of the other water-solubilizing esters are that many of the amino acid esters are crystalline and thus easily purified, are cleaved with a number of readily available lipases, and are useful for the synthesis of A-linked glycopeptides. ... 

For most free amino acids and small peptides, a mixture of alcohol with water is a typical mobile phase composition in the reversed-phase mode for glycopeptide CSPs. For some bifunctional amino acids and most other compounds, however, aqueous buffer is usually necessary to enhance resolution. The types of buffers dictate the retention, efficiency and - to a lesser effect - selectivity of analytes. Tri-ethylammonium acetate and ammonium nitrate are the most effective buffer systems, while sodium citrate is also effective for the separation of profens on vancomycin CSP, and ammonium acetate is the most appropriate for LC/MS applications. 

Polymers containing covalently bound monosaccharide and amino-acid residues are termed glycoproteins, glycopeptides or peptidogiycans. It is not possible to give... 

Several results are quite apparent from the data shown in Table II. It is evident from the pentapeptide model compounds that substitution of amino acid residues at positions 4 and 5 does not significantly affect the structure about the N-terminus. This observation corroborated earlier work from agglutination-inhibition assays, which demonstrated that the nature of the amino acid at position 4 of the peptide (or glycopeptide) is not a requirement for specificity. 

RPLC was used for the simultaneous determination of amino acids and amino sugars, including galactosamine and glucosamine, in glycopeptide analysis.124... 

During the synthesis of glycopeptides, Pavia and coworkers had to confront the proposition that racemization of the amino acids may occur during either the peptide-coupling stage, or the glycosylation stage, or both. This presented a potential problem that had to be resolved. 

One of the most unusual carbohydrate - amino acid linkages so far found in Nature is the thio linkage between glucose or galactose and cysteine.35,40 41 This glycopeptide has not yet been isolated or synthesized. Therefore, in order to obtain 13C-n.m.r. chemical-shift data for... 

Haase C, Seitz O (2007) Chemical Synthesis of Glycopeptides. 267 1-36 Hahn F, Schepers U (2007) Solid Phase Chemistry for the Directed Synthesis of Biologically Active Polyamine Analogs, Derivatives, and Conjugates. 278 135-208 Hansen SG, Skrydstrup T (2006) Modification of Amino Acids, Peptides, and Carbohydrates through Radical Chemistry. 264 135-162... 

Owing to flexibility in the substrate, the TycATE was also used to synthesize a variety of novel cyclic structures. Inclusion of a propargylated amino acid into the linear substrate allowed the synthesis of over 247 macrocyclic glycopeptides, where azido-sugars were coupled onto the cyclized alkyne via copper-catalyzed 1,3-dipolar cycloaddition [44] (Figure 13.12). 

Using the ethyl 1 -thio derivative (97) of 2,3,4-tri-O-benzoyl-D-xylose, the fully protected and free O-glycopeptides 99 and 100, having the TV-terminal amino acid sequence 3 to 6 (98) of the protein core of a proteodermatan sulfate have been prepared (69). 

Sequential solid-phase glycopeptide synthesis using glycosylated amino acid building blocks... 

The most effective and general route to synthetic glycopeptides includes the employment of glycosylated amino acids in stepwise solid-phase syntheses based on... 

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