• Archives of Pharmacal Research
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• 제18권5호
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• pp.369-370
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• 1995

• Bulletin of the Korean Chemical Society
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• 제25권10호
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• pp.1471-1473
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• 2004

An efficient dynamic kinetic resolution of racemic ${\beta}$-hydroxyalkylferrocene and 1,1'-bis( ${\beta}$-hydroxyalkyl)-ferrocene derivatives was achieved using lipase/ruthenium-catalyzed transesterification in the presence of an acyl donor. The racemic ${\beta}$-hydroxyalkylferrocene derivatives were successfully transformed to the corresponding chiral acetates of high optical purities in high yields.

• 공업화학
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• 제17권6호
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• pp.658-664
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• 2006

$\rho$, $\alpha$-dimethyl benzyl alcohol을 효과적으로 분할하기 위하여 2상 동적 속도론적 광학분할(biphasic dynamic kinetic resolution, DKR)반응을 실시하였다. 라세미화 반응을 위하여 촉매로 산성 제올라이트를 사용하였고 속도론적 광학분할(kinetic resolution, KR)을 위하여 고정화 효소를 촉매로 사용하였다. 유기용매와 물을 용매로 사용하는 이상 DKR 반응에서, acyl donor, 반응온도, 기질의 농도, 두 가지 촉매의 상대적 비율 및 교반속도 등의 공정변수를 변화시켜가면서 DKR반응의 전환율과 생성물의 광학순도에 미치는 영향을 조사하였다. 그 결과, $\rho$, $\alpha$-dimethyl benzyl alcohol의 DKR 반응에서 99% 이상의 광학순도를 가지는 생성물을 최대 88%의 높은 수율로 얻을 수 있었으며, 높은 TON에서도 반응의 효율성이 유지되었고 촉매의 재사용 시에도 지속적인 활성을 나타내었다.

• Bulletin of the Korean Chemical Society
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• 제32권11호
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• pp.4067-4070
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• 2011

• Bulletin of the Korean Chemical Society
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• 제28권11호
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• pp.2096-2098
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• 2007

• Journal of Microbiology and Biotechnology
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• 제17권1호
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• pp.74-80
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• 2007

An enantioselective lipase gene (esf) for the kinetic resolution of optically active (S)-flurbiprofen was cloned from the new strain Serratia marcescens ES-2. The esf gene was composed of a 1,845-bp open reading frame encoding 614 amino acid residues with a calculated molecular mass of 64,978 Da. The lipase expressed in E. coli was purified by a three-step procedure, and it showed preferential substrate specificity toward the medium-chain-length fatty acids. The esf gene encoding the enantioselective lipase was reintroduced into the parent strain S. marcescens ES-2 for secretory overexpression. The transformant S. marcescens BESF secreted up to 217kU/ml of the enantioselective lipase, about 54-fold more than the parent strain, after supplementing 3.0% Triton X-207. The kinetic resolution of (S)-flurbiprofen was carried out even at an extremely high (R,S)-flurbiprofen ethyl ester [(R,S)-FEE] concentration of 500 mM, 130 kU of the S. marcescens ES-2 lipase per mmol of (R,S)-FEE, and 1,000 mM of succinyl ${\beta}-cyclodextrin$ as the dispenser at $37^{\circ}C$ for 12h, achieving the high enantiomeric excess and conversion yield of 98% and 48%, respectively.

• Bulletin of the Korean Chemical Society
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• 제26권6호
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• pp.989-992
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• 2005

Dynamic kinetic resolution of $\alpha$-bromo carboxylic acid derivatives in nucleophilic substitution with chiral $\alpha$-amino ester nucleophiles in the presence of TBAI and DIEA has been investigated for stereoselective syntheses of 1,1'-iminodicarboxylic acid derivatives. Nucleophilic substitutions with various chiral $\alpha$-amino esters gave iminodiacetates 2-8 with stereoselectivities up to 87 : 13 dr. Also, the reactions of N-($\alpha$-bromo-$\alpha$-phenylacetyl)-L-alanine methyl ester with L-alanine, D-alanine and glycine methyl ester nucleophiles afforded N-carboxyalkyl dipeptide analogues 10-12 up to 90 : 10 dr.

• Bulletin of the Korean Chemical Society
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• 제27권3호
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• pp.447-449
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• 2006

• Bulletin of the Korean Chemical Society
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• 제32권5호
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• pp.1741-1744
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• 2011

• Bulletin of the Korean Chemical Society
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• 제35권1호
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• pp.265-268
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• 2014