• Proceedings of the Korean Information Science Society Conference
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• 2006.10a
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• pp.563-567
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• 2006

현재 IT분야의 끊임없는 발전과 더불어 BT/NT 분야와의 협업이 활발히 진행되고 있는 가운데, 광학 이성질체에 대한 연구는 그 중요성이 점점 증가되고 있다. 광학 이성질체는 생체 내에서 작용할 경우 성질, 기능, 효과에서 정반대 결과를 일으키기에 제약 산업 등 응용분야에서는 사용을 위해 효과적으로 식별하여 분리할 필요성이 존재한다. 이런 실험은 단계가 복잡하고 결과를 분석하고 시각화하기 어렵다. 이를 해결하기 위해 본 논문에서는 광학 이성질체의 분리연구를 위한 그리드 기반의 Chiral-MGrid 시스템을 제공한다. Chiral-MGrid 시스템은 분리연구 관련 실험을 그리드 기반에서 one set operation으로 수행할 수 있는 서비스를 제공한다.

• Bulletin of the Korean Chemical Society
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• v.8 no.4
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• pp.276-280
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• 1987

Several chiral potassium B-alkyl-9-boratabicyclo[3.3.1]nonanes $(K\; B-R^*-9-BBNH)$ and potassium B-alkoxy-9-boratabicyclo[3.3.1]nonanes $(K \;B-OR^*-9-BBNH)$ were synthesized by treatment of the corresponding trialkylboranes and dialkylmonoalkoxyboranes with a small excess of potassium hydride. The chiral B-alkoxy derivatives generally reduce representative ketones, such as acetophenone and 3-methyl-2-butanone, with greater optical induction than the corresponding B-alkyl derivatives, suggesting the involvement of the oxygen atom in the control process for asymmetric synthesis.

• Bulletin of the Korean Chemical Society
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• v.16 no.4
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• pp.344-348
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• 1995

As an effort to elucidate the chiral recognition mechanisms exerted by the (S)-naproxen-derived CSP bearing both π-acidic and π-basic sites, a homologues series of π-basic N-acyl-α-(1-naphthyl)alkylamines and π-acidic N-(3,5-dinitrobenzoyl)-α-amino esters were prepared and resolved. Based on the chromatographic resolution trends of the homologues series of analytes on the (S)-naproxen-derived chiral stationary phase, we proposed chiral recognition mechanisms which demonstrate that the intercalation of the substituent in the analyte molecule between the strands of bonded phase does significantly influence the enantioselectivity for resolving N-acyl-α-(1-naphthyl)alkylamines but the intercalation process is not involved in resolving N-(3,5-dinitrobenzoyl)-α-amino esters.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.278.1-278.1
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• 2003

Recently, particular attention has been paid to the chiral separation of amino acid enantiomers because of their different biological activities. Hence, the high optical purity of aromatic amino acids is critical because of their important functions in the central nervous system. For the accurate chiral discrimination. we attempted to exploit the crosschecking each enantiomeric migraion orders of aromatic amino acids measured using (+)-18C6H4TA and (-)-18C6H4TA as the chiral selectors under pH 2.0, tris/citric acid buffer.

• Bulletin of the Korean Chemical Society
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• v.26 no.5
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• pp.769-775
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• 2005

An efficiency of Monte Carlo (MC) docking simulations was examined for the prediction of chiral discrimination by cyclodextrins. Docking simulations were performed with various computational parameters for the chiral discrimination of a series of 17 enantiomers by $\beta$-cyclodextrin ($\beta$-CD) or by 6-amino-6-deoxy-$\beta$-cyclodextrin (am-$\beta$-CD). A total of 30 sets of enantiomeric complexes were tested to find the optimal simulation parameters for accurate predictions. Rigid-body MC docking simulations gave more accurate predictions than flexible docking simulations. The accuracy was also affected by both the simulation temperature and the kind of force field. The prediction rate of chiral preference was improved by as much as 76.7% when rigid-body MC docking simulations were performed at low-temperatures (100 K) with a sugar22 parameter set in the CHARMM force field. Our approach for MC docking simulations suggested that the conformational rigidity of both the host and guest molecule, due to either the low-temperature or rigid-body docking condition, contributed greatly to the prediction of chiral discrimination.

• Bulletin of the Korean Chemical Society
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• v.27 no.5
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• pp.637-641
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• 2006

Although chiral separation has been one of the main topics of chromatographic practice for over twenty-five years, it still presents many difficulties. In this work, the ultrasonic dependence of chiral resolution was investigated at various temperatures to improve resolution and reduce analysis time. The chiral resolution was performed on recently commercialized two HPLC chiral stationary phases (CSP 1 and CSP 2) with the analogues of racemic N-acylnaphthylethylamines (1a-d) and racemic amino acid derivatives (2a-c, 3a-c) as analytes. The CSP 1 was prepared from a (R)-N-(3,5-dinitrobenzoyl)phenylglycinol and the CSP 2 was prepared from a (S)-N-3,5-(dinitrobenzoyl) leucine. From the comparison of the chromatographic results under sonic condition with those under non-sonic condition, we found that the ultrasound decreased the elution time in chiral chromatography at all temperatures and improved the enantioselectivity at high temperature (45, 50, 60 ${^{\circ}C}$).

• Analytical Science and Technology
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• v.24 no.5
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• pp.360-367
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• 2011

Optical purities of 10 commercialized naproxens prepared from eight Korean drug companies were examined by an optimized chiral HPLC condition. The Chiralcel OD-H column and ChiralHyun-LE(S)-1 column were used as chiral stationary phases and the mixed eluent of hexane/isopropanol/acetic acid as 100:2.85:0.1 was used as a mobile phase for effective enantioseparation. Optical purity values of most samples were higher than 97 percents, only one of them was about 95 percents. The average relative standard deviation of them appeared very small (0.034%).

• Journal of Pharmaceutical Investigation
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• v.35 no.1
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• pp.57-63
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• 2005

Numerous drugs are chiral because they possess one or more chiral centers. Enantiomers may differ in their pharmacokinetic, pharmacological and toxicological properties. However, the significance of stereochemistry of drugs in their therapeutic uses has received relatively little attention until recently. The US FDA issued a guideline on stereoisomeric drugs in 1992, and the European agency describes tests for new drug substances which are optically active in an ICH(International Conference of Harmonization) guideline. According to the guidance, enantiomers may differ in their pharmacokinetic, pharmacological and toxicological properties. Therefore, in this paper, we examined the recently published Canadian guidance, stereochemical issues in chiral drug development, which will be references to make a guidance on stereochemical issues in chiral drug development in Korea.

• Analytical Science and Technology
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• v.23 no.1
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• pp.97-101
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• 2010

(R)-N-3,5-dinitrobenzoyl (DNB) phenylglycinol derived chiral selector was used as a HPLC chiral stationary phase (CSP) for the resolution of racemic N-acylnaphthylalkylamines. In this study, determination of optical purity was performed by both chiral chromatography and NMR spectroscopy by using the (R)-phenylglycinol derived chiral selector. The data of accuracy and precision of each optical purity value are calculated from the results of NMR and HPLC experiments by comparing with true value. Average error of the NMR method was +2.2% with average RSD of 4.54%, while that of HPLC method was -3.5% with average RSD of 3.23%.

• KSBB Journal
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• v.28 no.6
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• pp.423-427
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• 2013

A new convenient derivatization method of ${\alpha}$-amino acid esters as nitrobenzoxadiazole (NBD) derivatives for chiral resolution was introduced and the enantiomer separation of ${\alpha}$-amino acid esters as NBD derivatives was performed by normal HPLC using chiral columns based on polysaccharide derivatives. The NBD derivatives were readily prepared by stirring NBD-Cl and ${\alpha}$-amino acid methyl ester HCl with $NaHCO_3$ in ethanol. The performance of Chiralpak IA was superior to the other chiral stationary phases for enantiomer resolution of NBD derivatives of several ${\alpha}$-amino acid methyl esters. Owing to fluorescence detection as well as strong UV absorption, it is expected that the convenient analytical method developed in this study will be very useful for enantiomer separation of ${\alpha}$-amino acid esters as NBD derivatives on polysaccharide-derived chiral columns.