Enantioselective liquid chiral stationary phases

Fried, K.M., Koch, P, and Wainer, I.W., Determination of the enantiomers of albuterol in human and canine plasma by enantioselective high-performance liquid chromatography on a teicoplanin-based chiral stationary phase. Chirality, 10, 484, 1998. 

Levin, S., Abu-Lafi, S., The Role of Enantioselective Liquid Chromatography Separations Using Chiral Stationary Phases in Pharmaceutical Analysis, In Advances in Chromatography, Grushka, E. and Brown, P. R., Eds., Vol. 33, Marcel Dekker, New York, pp. 233-266, 1993. 

The preparative-scale separation of enantiomers on chiral stationary phases (CSPs) by GC cannot match the overwhelming success achieved in the realm of liquid chromatography (LC) (Francotte, 1994, 1996 and 2001). Modern commercial instrumentation for preparative-scale GC is not readily available. In contrast to LC, separation factors a in enantioselective GC are usually small (a = 1.01 - 1.20). This is beneficial for fast analytical separations but detrimental to preparative-scale separations. Only in rare instances are large chiral separation factors (a > 1.5) observed in enantioselective GC. Only in one instance, a separation factor as high as a = 10 was detected in enantioselective GC for a chiral fluorinated diether and a modified 7-cyclodextrin (Schurig and Schmidt, 2003) (vide supra). 

T. A. G. Noctor and I. W. Wainer, The use of displacement chromatography to alter retention and enantioselectivity on a human serum albumin-based HPLC chiral stationary phase A mini review, J. Liquid Chromatogr., 16 183 (1993). 

Levin, S. and Abu-Lafi, S. The Role of Enantioselective Liquid Chromatographic Separations Using Chiral Stationary Phases in Pharmaceutical Analysis , in Advances in Chromatography. 

The use of chiral stationary phases (CSP) in liquid chromatography continues to grow at an impressive rate. These CSPs contain natural materials such as cellulose and starch as well as totally synthetic materials, utilizing enantioselective and retentive mechanisms ranging from inclusion complexation to Ti-electron interactions. The major structural features found in chiral stationary phases include cellulose, starch, cyclodextrins, synthetic polymers, proteins, crown ethers, metal complexes, and aromatic w-electron systems. 

Bortocan, R. Lanchote, V.L. Cesarino, E.J. Bonato, P.S. Enantioselective analysis of disopyra-mide and mono-Y-dealkyldisopyramide in plasma and urine by high-performance liquid chromatography on an amylose-derived chiral stationary phase. J. Chromatogr. B 2000, 744, 299-306. 

Ghanem, A., Hoenen, H., Aboul-Enein, H. Y. Application and comparison of immobilized and coated amylose tris-(3,5-dimethylphenylcarbamate) chiral stationary phases for the enantioselective separation ofb-blockers enantiomers by liquid chromatography, Talanta, 2006, 68, 602-609. 

Wainer, 1. W. Enantioselective high-performance liquid affinity chromatography as a probe ofligand-biopolymer interactions an overview of a different use for high-performance liquid chromatographic chiral stationary phases,... 

K. H. Enantioselective separation of racemic secondary amines on a chiral crown ether-based liquid chromatography stationary phase, J. Chromatogr. A, 2002,... 

Mills, M.H. Mather, L.E. Gu, X.S. Hueuig, J.L. Determination of ketorolac enantiomers in plasma using enantioselective liquid chromatography on an ai-acid glycoprotein chiral stationary phase and ultraviolet detection. J.Chromatogr.B, 1994, 658, 177-182... 

Lammerhofer, M. (2010) Chiral recognition by enantioselective liquid chromatography mechanisms and modern chiral stationary phases. Review article./. Chromatogr. A, 1217, 814—856. 

Terminal alkynes substituted with chiral substituents have been polymerized by using a rhodium catalyst, [RhCl(NBD)]2 (NBD = norbomadiene) [6]. As shown in Scheme 3, polymerization of a chiral (carbamoyloxy)phenylacetylene 4 forms a cis-substituted polyacetylene 5. Due to the bulkiness of the substituents, these polymers show a helical conformation with no extended conjugation in the polymer chain. These materials are potentially useful as enantioselective permeable membranes to separate racemic amino acids and alcohols in water or in methanol. They can be also used as chiral stationary phase for enantioselective high-performance liquid chromatography (HPLC) analysis. 

Tan X, Hou S, Wang M (2007) Enantioselective and diastereoselective separation of synthetic pyrethroid insecticides on a novel chiral stationary phase by high-performance liquid chromatography. Chirality 19 574—580... 

Bosakova, Z., Cufinovd, E., and Tes ovd, E., Comparison of vancomycin-based stationary phases with different chiral selector coverage for enantioselective separation of selected drugs in high-performance liquid chromatography, J. Chromatogr. A, 1088, 94, 2005. 

Recently, optically active polythiophenes, incorporating as ring substituents chiral selectors such as (R)-(-)- and CS )-(+)-/V-(3,5-dinitrobcnzoyl)-a-phcnylglycinc used in Pirkle-type stationary phases, have been synthesized.167 These may have potential in enantioselective analysis of chiral chemicals using high performance liquid chromatography (HPLC). 

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