CSPs , glycopeptides containing

SYNTHETIC STRATEGIES FOR THE PREPARATION OF GLYCOPEPTIDES CONTAINING CSPs FOR HPLC... 

ENANTIOSELECTIVE HPLC SEPARATIONS USING THE GLYCOPEPTIDES CONTAINING CSPs... 

If a certain analyte contains more than one polar functional groups capable of interacting with the glycopeptide-containing CSP and at least one of these groups is near the... 

The majority of the HPLC chiral separations obtained with glycopeptides-containing CSPs are anyway achieved by UV/visible (see Section 2.3.2) or fluorescence [102] detection. 

Since the natural target of macrocyclic antibiotics is the A-acyl-D-alanyl-D-alanine terminus (see Section 2.1), the early choice of suitable substrates for this kind of CSPs was that of amino acids [45]. However, it turned out that the macrocyclic CSPs were very successful not only in amino acids enantioresolution, but also in the separation of a wide variety of different structures. The early stages of application of macrocyclic antibiotics have been surveyed in the different fields of chromatography [1,2]. A summary of the different categories of chiral compounds separated by HPLC on glycopeptides containing CSPs is reported in Table 2.3. 

Classes of Compounds Separated by HPLC on Glycopeptides Containing CSPs... 

This class of compounds has been investigating on glycopeptides-containing CSPs for the past 2 years. Twelve underivatized 5-lactams were separated on commercially... 

Alcaro, S et al., Glycopeptide-containing CSP new synthesis, apphcations and insight into mechanism of chiral recognition, presented at 22 hit. Symp. on Chromatography, Roma, September 13-18, 1998, 39. 

Non steroidal antiinflammatory drugs were among the first classes of chiral compounds investigated in the early stages of the application of macrocyclic antibiotics as chiral selectors therefore, they were screened on vancomycin [7], teicoplanin [30], ristocetin A [33] CSPs under RPmode systems, and on avoparcin CSP under NP mode systems [37]. The enantioresolution of a variety of pro fens was later reported on commercially available vancomycin CSPs [128, 168], and recently on a ME-TAG CSP [58]. Ibuprofen enantiomers were also separated on a CDP-1-containing CSP [55]. Glycopeptide A-40,926 CSP was successfully employed in the analytical and semipreparative separation of 2-arylpropionic acids [63]. 

The most popular and commonly used chiral stationary phases (CSPs) are polysaccharides, cyclodextrins, macrocyclic glycopeptide antibiotics, Pirkle types, proteins, ligand exchangers, and crown ether based. The art of the chiral resolution on these CSPs has been discussed in detail in Chapters 2-8, respectively. Apart from these CSPs, the chiral resolutions of some racemic compounds have also been reported on other CSPs containing different chiral molecules and polymers. These other types of CSP are based on the use of chiral molecules such as alkaloids, amides, amines, acids, and synthetic polymers. These CSPs have proved to be very useful for the chiral resolutions due to some specific requirements. Moreover, the chiral resolution can be predicted on the CSPs obtained by the molecular imprinted techniques. The chiral resolution on these miscellaneous CSPs using liquid chromatography is discussed in this chapter. 

We performed this difficult study using the Supelco Chirobiotic0 CSPs based on macrocyclic glycopeptide selectors. The system parameters, e, s, a, b, and v, of the four different columns, namely ristocetin, vancomycin, teicoplanin, and teicoplanin aglycon, were obtained for six different normal heptane-ethanol mobile phases and ten different acetonitrile or methanol-water reversed mobile phases [47, 48]. The 44 achiral probe solutes contained aldehydes, ketones, amides, halogenated phenols, nitro-substituted benzenes, and nitro-alkanes. About 2,400 chromatograms were needed to obtain the 5 fl-v system parameters for the 4 CSP columns and the 16 mobile phases [47]. 

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