• Proceedings of the PSK Conference
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• 2002.10a
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• pp.395.1-395.1
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• 2002

Many of the chiral NSAIDs are marketed as racemates. There is an increasing interest in developing the enantiomerically pure forms of the NSAIDs because the anti-inflammatory activity of NSAIDs have previously been shown to be largely sterospecific for the (S)-(＋)-enantiomer. Therefore, simple and economic preparative method to identify the (S)-(＋)-enantiomer of NSAIDs (aryl propionic acids) as diastereomeric solvation complex was developed using several chiral solvating agents by recrystallization of racemate and solvent fractionation. (omitted)

• KSBB Journal
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• v.21 no.5
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• pp.371-375
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• 2006

Frontal analysis(FA) and Pulsed input method(PIM) have been frequently utilized to measure isotherm of single solute, as well as non-competitive isotherms of two solutes in chromatography(1). FA and PIM were used in this study as complementary methods to measure adsorption isotherms of loxoprofen racemate in HPLC. Prior to FA and PIM experiments, measurements of loxoprofen solubility were made at hexane/ethanol=50/50, 80/20, 95/5(v/v) with acetic acid(0.5%) for adjusting pH. The last composition(95/5) of hexane/ethanol allows us to separate loxoprofen racemate into two forms(retentate, extract). PIM and FA were used to determine the isotherms of re-and ex-loxoprofen.

• Journal of Integrative Natural Science
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• v.4 no.4
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• pp.315-322
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• 2011

This study was performed to investigate the current regulatory guidances of safety and efficacy evaluation for the approval of stereoisomeric drugs in Korea and US. According to the regulatory guidelines in major countries (EU, Canada, US), the important categories for the development of stereoisomeric drugs are classified as 1) development of a single enantiomer as a new active substances 2) development of a racemate as a new active substance 3) development of a new single enantiomer from an approved racemate. For this study, domestic regulatory documents for current guidelines of stereoisomeric drugs were investigated. Also four typical stereoisomeric drugs for three categories were chosen to investigate the new drug submission documents of KFDA and FDA for the safety and efficacy evaluation of stereoisomeric drugs. It is expected that these comparative results between KFDA and FDA will be useful for the safety and efficacy for the regulatory approval of stereoisomeric drugs in Korea.

• Applied Chemistry for Engineering
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• v.19 no.3
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• pp.287-294
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• 2008

Molecularly imprinted polymer (MIPs) membranes were prepared by UV polymerization to separate racemates with opposite physiological activity, and then its separation selectivity of racemates was carried out. Likewise, their properties were examined. Polycarbonate (PC) membrane was polymerized as small spot form in pore inner wall, but anodisc (AD) membrane was polymerized as film form with thickness 500~700 nm onto the membrane surface. Also the study on the separation selectivity of prepared MIPs membranes was carried out in L-Tryptophane (Trp) racemate solution. The results showed that AD MIPs membrane polymerized as a film form, which was achieved by solution polymerizaion consisting of over 90% cross-linking agent (ethylene glycol dimethacrylate; EGDMA) and under 30% dispersing agent (methanol; MeOH), had predominant 3.5 selectivity.

• Advances in materials Research
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• v.2 no.1
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• pp.51-64
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• 2013

Enantioselective macromer of trimesic acid was prepared using S(-) menthol with trimesoyl chloride on polyimide (PI) ultrafiltration membrane. The chemical composition of macromer as well as polyimide ultrafiltration membrane was determined by ATR-FTIR Spectroscopy. The optical resolution of chiral alcohols was performed in pressure driven process. The effect of monomer solutions concentration, effect of air-drying time of S(-) menthol solution, effect of reaction time, effect of operating pressure, effect of feed concentration of racemate on the performance of macromer was studied. The synthesised material exhibits separation of chiral alcohols (menthol ~23% and sobrelol ~21%).

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.549-553
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• 2003

SMB(simulated moving bed) chromatography system has been developed to realize continuous separation and save solvent consumption for binary mixture such as chiral compounds in especial. The parameters of SMB chromatography system can be calculated from mass balance equations of true moving bed chromatography, and they are used in design of 6-column SMB chromatography. We can separate 1'R-25 and 1'S-2S enantiomers as a raffinate product in 95% of purity using assembled SMB chromatography system.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1338-1342
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• 2004

Cyclosophoraoses (Cys), cyclic ${\beta}-(1{\rightarrow}2)-D-glucans$ produced by Rhizobium meliloti 2011, were used as a novel chiral stationary phase for the enantiomeric separation. A novel Cys stationary phase, chemically immobilized onto porous silica via aminopropyltrimethoxysilane as a molecular linker, showed good separation for each racemate of bupivacain (separation factor, $\alpha$=1.3), propranolol ($\alpha$=1.3), and fenoprofen ($\alpha$=2.9), respectively, under the mobile phase of water: methanol (80:20, v/v) at a constant flow rate of 0.9 ml/min at pH7.

• YAKHAK HOEJI
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• v.54 no.6
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• pp.474-480
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• 2010

Conformationally locked nucleosides are important in searching selective agonists and antagonists for P2Y receptors. There were two previous synthetic works of the crucial intermediate, cyclopentenyl alcohol (3), which had some inefficiency like using too strong dianionic base and synthesis of racemate. Here we describes a facile synthesis of the intermediate using Sharpless epoxidation and the opening of epoxide ring using zinc, followed by Grubb's metathesis as key steps. The intermediate was converted to the southern bicyclo[3.2.0]heptane for confirming its usefulness.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.197-197
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• 2001

The effect of CYP2C19 genetic polymorphism on the disposition of lansoprazole enantiomers was determined in order to evaluate the contribution of CYP2Cl9 in the stereoselective metabolism of lansoprazole. After single oral dose of 30mg lansoprazole racemate in 6 subjects with CYP2C19 PM genotype and 6 with EM genotype, the plasma concentrations of R-enantimers were consistently higher than those of S-enantiomer in boty EM and PM subjects.(omitted)

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.5
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• pp.306-308
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• 2003

Enantioselective hydrolysis for the production of chiral styrene oxide was investigated using the epoxide hydrolase activity of a newly isolated Rhodosporidium kratochvilovae SYU-08. The effects of reaction parameters - buffer type, pH, temperature, initial substrate concentrations, phenyl-1,2-ethanediol concentrations on hydrolysis rate, and enantioselectivity - were analyzed. Optically active (S)-styrene oxide with an enantiomeric excess higher than 99 % was obtained from its racemate. with a yield of 38 % (theoretically 50% maximum yield) from an initial concentration of 80 mM.