• Journal of Integrative Natural Science
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• v.9 no.1
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• pp.28-34
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• 2016

A number of chiral selectors have been developed and applied for enantiomer separation of a variety of chiral compounds. Among these chiral selectors are chiral crown ethers, a class of synthetic host polyether molecules that bind protonated chiral primary amines with high selectivity and affinity. In this paper, two important chiral crown ethers as chiral selectors of bis-(1,1'-binaphthyl)-22-crown-6 and (18-crown-6)-2,3,11,12-tetracarboxylic acid (18-C-6-TA) are focused. They have been widely used to resolve the enantiomers of chiral compounds containing a primary amino moiety using chiral stationary phases (CSPs) or chiral selectors by high-performance liquid chromatography (HPLC), capillary electrophoresis (CE) and so on in chirotechnology. Also, it was described that the commercially available covalent type HPLC CSPs derived from (+)- and (-)-18-C-6-TA have been developed and successfully applied for the resolution of various primary amino compounds including amino acids.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.167-168
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• 2002

Because of the differences between biological and pharmacological properties of chiral drugs in human body, accurate determinations of their optical purities have been in great need. There are two major approaches in chiral separation: indirect method performed under achiral condition, and direct method under the chiral environment. We have been conducting chiral separation of acidic chiral compounds and also amino acidic chiral compounds employing indirect GC methods and direct CE enantiomeric separation methods. (omitted)

• Bulletin of the Korean Chemical Society
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• v.34 no.6
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• pp.1809-1813
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• 2013

Sulfated ${\beta}$-cyclodextrin (SCD)-coated zirconia monolith was used as the chiral stationary phase in capillary electrochromatography for enantiomeric separation of basic chiral compounds. SCD adsorbed on the zirconia surface provided a stable chiral stationary phase in reversed-phase eluents. Retention, chiral selectivity and resolution of a set of six basic chiral compounds were measured in eluents of varying pH, composition of methanol and buffer. Optimum mobile phase condition for the separation of the compounds was found to be methanol content of 30%, buffer concentration of 30 mM and pH of 4.0.

• KSBB Journal
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• v.15 no.6
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• pp.541-547
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• 2000

Simulated moving bed (SMB) chromatography has been investigated in order to separate chiral compounds for pharmaceutical use. SMB utilizes the principle of true moving bed (TMB) chromatography, and has the advantages of low solvent usage, flexible configuration of columns and hardwares, and high productivity of the chiral compounds over the TMB. Large scale separation of xylene isomers and saccharides has been conducted since 1960s. However, the application of SMB in the fine chemical industries is still in the infant stage. The study of SMB for the chiral compounds production was initiated in the mid 1990s and further researches are actively undergoing. This review summarizes the principle of SMB as well as the chemistry of chiral stationary phase and chiral compounds.

• KSBB Journal
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• v.20 no.3
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• pp.177-182
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• 2005

Simulated moving bed (SMB) chromatography was used in the petrochemical industry in the 1960s and its use has been widened to separate chiral compounds in the 1990s. Chiral stationary phase (CSP) is the key component in SMB for the separation of the chiral compounds. CSP has been developed for the analytical use in HPLC, however, its development successfully adapted for the preparative use in SMB chromatography. This review covers the present state-art technology of CSP for SMB chromatography in terms of selectivity, stability, and capacity.

• Bulletin of the Korean Chemical Society
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• v.26 no.8
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• pp.1153-1163
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• 2005

Crown ether-based HPLC chiral stationary phases (CSPs) have been successfully utilized in the resolution of various racemic compounds containing a primary amino group. Especially, CSPs based on chiral crown ethers incorporating chiral binaphthyl unit or tartaric acid unit and based on phenolic pseudo chiral crown ethers have shown high chiral recognition efficiency. In this account paper, a review on the development of crown etherbased HPLC CSPs, their structural characteristics and applications to the resolution of racemic compounds including chiral drugs containing a primary or secondary amino group with the variation of the type and the content of mobile phase components and with the variation of the column temperature is presented.

• KSBB Journal
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• v.27 no.4
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• pp.199-206
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• 2012

Chiral crown ethers are synthetic macrocyclic polyethers that bind protonated chiral primary amines with high selectivity and affinity. They have been widely used to separate or distinguish the enantiomers of chiral compounds containing a primary amino moiety by high-performance liquid chromatography, capillary electrophoresis, and NMR spectroscopy. In this paper, two important chiral crown ethers including chiral binaphthyl unit and (18-crown-6)-2,3,11,12-tetracarboxylic acid as chiral selectors are focused. And several chiral resolution techniques and their applications in chirotechnology using these chiral crown ethers with related chiral recognition mechanism studies are reviewed. Especially, it was shown that the commercially available HPLC columns based on (18-crown-6)-2,3,11,12-tetracarboxylic acid have been developed and successfully applied for the resolution of various primary amino compounds including amino acids.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.285.1-285.1
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• 2003

ChiroSil RCA(+) and SCA(-) HPLC chiral stationary phases (CSPs) developed by covalently bonding (+)- and (-)-(18-crown-6)-2,3,11,12-tetracarboxylic acid (18-C-6-T A) to silica gel were employed for enantioresolution of racemic amino compounds, respectively. Also, these 18-C-6-TA covalently bonded CSPs were compared to a commercially available Crownpak CR CSP prepared by coating chiral crown ether as a chiral selector on ODS column. (omitted)

• KSBB Journal
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• v.15 no.5
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• pp.415-422
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• 2000

Enzymatic resolution is becoming increasingly important in the production of optically active pharmaceutical drugs and is now challenging the traditional synthetic methods for production of a variety of chiral intermediates and products. This article reviews the recent advances in chirotechnology using enzymes as a catalyst to resolve chiral compounds. The review focuses on the recent trends in chirotechnology and the application of enzymes to the production of industrially valuable pharmaceutical drugs.

• Bulletin of the Korean Chemical Society
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• v.31 no.1
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• pp.82-86
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• 2010

Quinine (QN) is a weak anion-exchange type chiral selector and QN-based silica stationary phases have been widely used for enantioseparation of acidic chiral analytes in HPLC and recently in CEC. In this work we report enantioseparation of non-acidic chiral analytes on a quinine carbamate-immobilized zirconia (QNZ) in reversed-phase (RP) CEC. Influences of pH, composition of the buffer, acetonitrile content and the applied voltage on enantioseparation were examined. Enantiomers of the analytes investigated are well separated in acetonitrile/phosphate buffer mobile phases. Separation data on QNZ were compared to those on QN-bonded silica (QNS). Retention was longer but better enantioselectivity and resolution were obtained on QNZ than QNS.