• Bulletin of the Korean Chemical Society
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• 제28권11호
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• pp.2015-2019
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• 2007

The article reports the synthesis of a novel bispyridino-18-crown-6 ether, 7-{[(5S,15S)-5,15-diphenyl- 3,6,14,17-tetraoxa-23,24-diazatricyclo[17.3.1.18,12]tetracosa-1(23),8(24),9,11,19,21-hexaen-10-yl]oxy}heptylferrocenamide 6, bearing the C2-symmetric diphenyl substituents as chiral barriers and the ferrocenyl groups serving as an electrochemical sensor, and its electrochemical study with D- and L-AlaOMe·HCl as the guest by cyclovoltametry.

• Bulletin of the Korean Chemical Society
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• 제16권10호
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• pp.977-980
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• 1995

A new chiral stationary phase (CSP 2) derived from cyclohexylamide of (S)-naproxen has been prepared. CSP 2 has shown greater enantioselectivities for the two enantiomers of N-(3,5-dinitrobenzoyl)-a-amino esters and amides than the CSP derived from 3,5-dimethylanilide of (S)-naproxen (CSP 1) as expected from the reciprocity conception of chiral recognition. However, CSP 2 has been found to be worse than CSP 1 in resolving N-(3,5-dinitrobenzoyl)-a-arylalkylamines, supporting the previously proposed chiral recognition mechanism which utilizes the 3,5-dimethylphenyl group of CSP 1 as an alternative π-basic interaction site. In addition, CSP 2 has been found to be reasonably good in resolving the two enantiomers of a variety of other π-acidic racemates.

• Bulletin of the Korean Chemical Society
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• 제10권6호
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• pp.578-581
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• 1989

Two enantiomers of various 2-hydroxy acid esters have been resolved as the 3,5-dinitrophenyl carbamates on chiral stationary phases (CSPs) derived from ${\alpha}-arylalkylamines.$ Two CSPs, each of which contains the same type of chiral moiety, but shows different mode of connection to a silica support, have been found to show the contrasting resolution behaviors. From the contrasting resolution behaviours of two CSPs used in this study, two competing chiral recognition mechanisms are proposed.

• KSBB Journal
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• 제27권4호
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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.

• Bulletin of the Korean Chemical Society
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• 제24권11호
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• pp.1627-1631
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• 2003

Molecular modeling was performed to comprehend the chiral recognition of ${\alpha}$-methoxy-${\alpha}$-trifluoromethylphenylacetic acid (MTPA) enantiomers by cyclomaltoheptaose (${\beta}$-cyclodextrin,${\beta}$-CD) and 6-amino-6-deoxy-cyclomaltoheptaose (am-${\beta}$-CD). Monte Carlo (MC) docking coupled to constant temperature molecular dynamics (MD) simulations was applied to the investigation for the ${\alpha}$-methoxy-${\alpha}$-trifluoromethylphenylacetic acid complexation with two different CDs in terms of the relative distribution of the interaction energies. The calculated results are finely correlated with the experimental observations in chiral recognition thermodynamics. Am-${\beta}$-CD as a host showed the superior enantio-discrimination ability to the native ${\beta}$-CD where the amino group of am-${\beta}$-CD was critically involved in enhancing the ability of chiral discrimination via the Coulombic interaction with MTPA.

• Bulletin of the Korean Chemical Society
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• 제34권10호
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• pp.2978-2982
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• 2013

A doubly tethered $N-CH_3$ amide chiral stationary phase (CSP 4) based on (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid was applied to the resolution of an antiarrythmic agent, tocainide, and its analogues and the chromatographic resolution results were compared with those on a singly tethered N-H amide CSP (CSP 1), a singly tethered $N-CH_3$ amide CSP (CSP 2) and a doubly tethered N-H amide CSP (CSP 3) under an identical aqueous mobile phase condition. CSP 4 was found to be generally better than other CSPs in terms of the separation factors (${\alpha}$) and resolutions (RS). The retention times of analytes denoted by the retention factors ($k_1$) on CSP 4 were quite long compared to those on other CSPs because of the improved lipophilicity of CSP 4. The long retention times of analytes on CSP 4 were successfully controlled by the addition of a small amount of ammonium acetate to aqueous mobile phase without hurting the chiral recognition efficiency. The variation of the content and type of organic and acidic modifier in aqueous mobile phase was found not to change the chiral recognition efficiency significantly.

• 청정기술
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• 제22권2호
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• pp.75-81
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• 2016

문명의 발달과 더불어 경제적으로 생활이 윤택하여지고 산업기술이 고도화 되어감에 따라 평균수명이 급격히 연장되었고, 건강식품과 의약품에 대한 의존도와 수요도 급격하게 증가하는 추세이다. 최근에는 건강식품과 의약품의 부작용이 사회적인 이슈로 등장하고 부작용이 없는 의약품의 개발, 환경과 식품산업의 건전성 향상을 위해 신속 간편하며 정확하게 건강과 환경을 계측할 수 있는 기술의 개발 또한 시급한 과제로 부각되고 있다. 의약품의 생산 공정뿐만 아니라 소비자 스스로 자기 건강을 자가 진단하고자 하며, 자기가 먹는 음식의 안전성 여부와 자기가 사는 환경의 안전성 여부를 스스로 확인하고자 하는 욕구 또한 증대되고 있다. 본고에서는 키랄 의약품, 기존의 키랄 의약품 분리기술, 분자자기인식 기법, 그리고 분자자기인식 기법에 의한 키랄 의약품 분리기술 개발동향에 대한 간단한 소개와 분자자기인식 기법에 의한 키랄 의약품 분리ㆍ분석 기술 개발 현황과 그 시장성에 대해 고찰하고자 한다.

• KSBB Journal
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• 제29권3호
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• pp.205-209
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• 2014

Chromatographic enantiomer resolution of chiral amines was performed on several covalently immobilized and coated chiral stationary phases (CSPs) based on polysaccharide derivatives under the mobile phase conditions containing base or acid or acid/base additive. The chromatographic parameters including separation factors and capacity factors were greatly influenced by the nature of the mobile phase containing base or acid or salt additive as well as the used CSPs. When 0.05% triethylamine/0.05% trifluoroacetic acid as an additive in the mobile phase was used on all CSPs in this study, the greatest enantiomer resolution was observed except for Chiralpak AD. Also, it was shown that the change of base additive into acid or salt in the mobile phase may directly affect chiral recognition mechanisms between the chiral selectors and analytes occurring during enantiomer separation, resulting in the change of elution orders.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.214.2-214.2
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• 2002

• Macromolecular Research
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• 제15권2호
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• pp.134-141
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• 2007

The direct chromatographic separation of enantiomers by chiral stationary phases (CSPs) has been extensively developed over the past two decades, and has now become the most popular method for the analytical and preparative separations of enantiomers. Polysaccharide derivatives coated onto silica gel, as CSPs, playa significantly important role in the enantioseparations of a wide range of chiral compounds using high-performance liquid chromatography (HPLC). Unfortunately, the strict solvent limitation of the mobile phases is the main defect in the method developments of these types of coated CSPs. Therefore, the immobilization of polysaccharide derivatives onto silica gel, via chemical bonding, to obtain a new generation of CSPs compatible with the universal solvents used in HPLC is increasingly important. In this article, our recent studies on the immobilization of polysaccharide derivatives onto the silica gel, as CSPs, through radical copolymerization with various vinyl monomers are reported. Polysaccharide derivatives, with low vinyl content, can be efficiently fixed onto silica gel with high chiral recognition.