Glycopeptide complex

Figure 6a. Analytical separations of a crude glycopeptide complex (isocratic). Sample crude antibiotic extract. Column Beckman Ultrasphere ODS, 5 jzm, 4.6 x 150 mm. Mobile phase 35%, acetonitrile in 0.1 M KH2P04pH 3.2. Flow 1.5 ml/min. Detection ...

Figure 7. Small-scale preparative separation of glycopeptide complex. Sample crude antibiotic extract (2 g). Column ...

Figure 9a. Small-scale preparative separation of glycopeptide complex on Magnum 40 column (4.5 x 50 cm). Sample purified antibiotic (2 g). Column Whatman Partisil Prep 40 0DS-3 (37-60 jxm). Mobile phase 20 to 26% acetonitrile in 0.1 M KH2PO4PH 6.0. Flow 100 ml/min. Detection 210 nm.

Figure 9b. Recovery data for small-scale separation of glycopeptide complex on Magnum 40 column. Sample purified component I. Column Beckman Ultrasphere 0DS, 5 xm, 4.6 x 150 mm).

Figure 10a. Scale-up preparative separation of glycopeptide complex (25 g run). Sample crude antibiotic complex (25 g).

This relatively new class of CSPs incorporates glycopeptides attached covalently to silica gel. These CSPs can be used in the normal phase, reversed phase, and polar organic modes in LC [62]. Various functional groups on the macrocyclic antibiotic molecule provide opportunities for tt-tt complexation, hydrogen bonding, and steric interactions between the analyte and the chiral selector. Association of the analyte... 

The complex oligosaccharides comprising the Y and T antennae of three glycoproteins have been studied by c.d. spectroscopy. Five antennae were studied in all, because two of the proteins have two closely related forms. The c.d. for the three fundamental oligosaccharides are given in Fig. 36. These are asparagine-linked glycopeptides, and the intense, conservative c.d. band that results from the interaction between the two amides has already been discussed in Section III,2. Fig. 36 shows that the c.d. spectra... 

Vancomycin is an antibiotic isolated from Strep, orientalis and has an empirical formula of C66H75CI2N9O4 (mol. wt 1448) it has a complex tricyclic glycopeptide structure. Modern chromatographically purified vancomycin gives rise to fewer side-effects than the antibiotic produced in the 1950s. 

A feasible way of introducing acid-stable linkages into carbohydrates is N-deacetylation. This can be achieved with hydrazine.59,70,71 The use of sodium hydroxide-sodium benzenethioxide in aqueous dimethyl sulfoxide for this purpose has also been described72 The difference in the acid hydrolysis of N-acetylhexosamine-con-taining carbohydrates before and after N-deacetylation was used in the study of complex glycoprotein saccharides from human erythrocyte membranes.73-75 Methylation analysis of the glycopeptides prepared... 

The combination of the N-terminal allyloxycarbonyl (Aloe) group (34) with the tert-butyl ester proved to be a particularly efficient tool in the synthesis of complex glycopeptides, as has been demonstrated in the synthesis of sensitive fucosyl chitobiose glycopeptides (19). The Aloe group was... 

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