Chiral stationary phases macrocyclic glycopeptides

Method Development and Optimization of Enantiomeric Separations Using Macrocyclic Glycopeptide Chiral Stationary Phases... 

Because plasma and urine are both aqueous matrixes, reverse-phase or polar organic mode enantiomeric separations are usually preferred as these approaches usually requires less elaborate sample preparation. Protein-, cyclodextrin-, and macrocyclic glycopeptide-based chiral stationary phases are the most commonly employed CSPs in the reverse phase mode. Also reverse phase and polar organic mode are more compatible mobile phases for mass spectrometers using electrospray ionization. Normal phase enantiomeric separations require more sample preparation (usually with at least one evaporation-to-dryness step). Therefore, normal phase CSPs are only used when a satisfactory enantiomeric separation cannot be obtained in reverse phase or polar organic mode. 

Ahoul-Enein, H.Y. and Ali, I. Macrocyclic glycopeptide antihiotics-hased chiral stationary phase, in Chiral Separation by Liquid Chromatography and Related Technologies, Marcel Dekker New York, 2003, chap. 2. 

Staroverov, S.M. et al.. New chiral stationary phase with macrocyclic glycopeptide antibiotic eremomycin chemically bonded to sihca, J. Chromatogr. A, 1108, 263, 2006. 

Petrusevska, K. et al.. Chromatographic enantioseparation of amino acids using a new chiral stationary phase based on a macrocyclic glycopeptide antibiotic, J. Sep. ScL, 29, 1447, 2006. 

Berthod, A. et al.. Evaluation of the macrocyclic glycopeptide A-40,926 as a high-performance liquid chromatographic chiral selector and comparison with teicoplanin chiral stationary phase, J. Chromatogr. A, 897, 113, 2000. 

Beesley, T.E., Lee, J.T., and Wang, A.X., Method development and optimization of enantiomeric separations using macrocyclic glycopeptide chiral stationary phases, in Chiral Separation Techniques, Second completely revised and updated edition, Subramanian, G., Ed., Wiley-VCH Weinheim, 2001, 25. 

Xiao, T.L., Reversal of enantiomeric elution order on macrocyclic glycopeptide chiral stationary phases, J. Liq. Chrom. Rel. TechnoL, 24, 2673, 2001. 

Sztojkov-lvanov, A. et al., Comparison of separation efficiency of macrocyclic glycopeptide-based chiral stationary phases for the LC enantioseparation of fi-amino acids, Chromatographia, 64, 89, 2006. 

Xiao, T.L. et al.. Separation of enantiomers of substituted dihydrofurocoumarins by HPLC using macrocyclic glycopeptide chiral stationary phases, Anal. Bioanal. Chem., 377, 639, 2003. 

Figure 4.10 shows the effect of additive concentration on the separation of clen-buterol enantiomers on a polysaccharide-based chiral stationary phase [79]. The peak shapes were dramatically improved by adding an amine additive and the separation time was also reduced from 14 to 7 min when 1.0% amine was added to the mobile phase. Phinney and Sander [100] investigated the effect of amine additives using chiral stationary phases having either a macrocyclic glycopeptide or a... 

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. 

The chiral recognition mechanisms in NLC and NCE devices are similar to conventional liquid chromatography and capillary electrophoresis with chiral mobile phase additives. It is important to note here that, to date, no chiral stationary phase has been developed in microfluidic devices. As discussed above polysaccharides, cyclodextrins, macrocyclic glycopeptide antibiotics, proteins, crown ethers, ligand exchangers, and Pirkle s type molecules are the most commonly used chiral selectors. These compounds... 

Aboul-Enein, H. and Ali, I. (2002) Optimization Strategies for HPLC Enantioseparation of Racemic Drugs Using Polysaccharides and Macrocyclic Glycopeptide Antibiotic Chiral Stationary Phases, Farmaco 57, 513-529. 

Tesarova and Bosakova [58] proposed an HPLC method for the enantio-selective separation of some phenothiazine and benzodiazepine derivatives on six different chiral stationary phases (CSPs). These selected CSPs, with respect to the structure of the separated compounds, were either based on b-CD chiral selectors (underivatized (J>-CD and hydroxypropyl ether (3-CD) or on macrocyclic antibiotics (vancomycin, teicoplanin, teicoplanin aglycon and ristocetin A). Measurements were carried out in a reversed-phase separation mode. The influence of mobile phase composition on retention and enantio-selective separation was studied. Enantioselective separation of phenothiazine derivatives, including levopromazine (LPZ), promethazine and thioridazine, was relatively difficult to achieve, but it was at least partly successful with both types of CSPs used in this work (CD-based and glycopeptide-based CSP), except for levomepromazine for which only the [CCD-based CSP was suitable. 

W. S., Armstrong, D. W. Separation of chiral sulfoxides by liquid chromatography using macrocyclic glycopeptide chiral stationary phases, J. Chromatogr. 

Liu,Y., Berthod, A., Mitchell, C. R., Xiao,T. L., Zhang, B., Armstrong, D. W. Super/subcritical fluid chromatography chiral separations with macrocyclic glycopeptide stationary phases, J. Chromati. A, 2002, 978, 185-204. 

The chromatographic system chosen to examine was the chiral stationary phase Chirobiotic V (as already described, this is a macrocyclic glycopeptide called Vancomycin bonded to silica gel particles 5 pm in diameter) which was used in the normal phase mode (solute retention controlled largely by polar interactions), employing mixtures of hexane and ethanol as the mobile phase. 

Protein Based Stationary Phases The Pirkle Type Stationary Phases Coated Cellulose and Amylose Derivatives Macrocyclic Glycopeptide Stationary Phases Cyclodextrin Based Chiral Stationary Phases Synopsis References Chapter 9... 

Since first demonstration in 1994 of the potential use of macrocyclic antibiotics as chiral selectors in analysis, glycopeptide antibiotics have been successfully applied for enantiomer separations by liquid chromatography, as recognition components of chiral stationary phases, and by capillary electrophoresis (CE) as soluble chiral selec-tors. Four chiral stationary phases for chromatography with the selectors vancomycin, ristocetin, teicoplanin, and the teicoplanin aglycone are commercialized under the trade name Chirobiotic by Astec and Supelco. Various aspects of analytical applications of glycopeptide antibiotics have been extensively covered in the recent reviews cited above. As an example. Table 2 shows some representative results for CE enantioseparations with vancomycin, ristocetin A, and teicoplanin, which were taken from Ref. 39. 

Han X, Huang Q, Ding J, Larock RC, Armstrong DW (2005) Enantiomeric separation of fused polycycles by HPLC with cyclodextrin and macrocyclic glycopeptides chiral stationary phases. Sep Sci Tech 40 2745-2759... 

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