• Bulletin of the Korean Chemical Society
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• v.32 no.spc8
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• pp.3120-3122
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• 2011

• Bulletin of the Korean Chemical Society
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• v.23 no.12
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• pp.1823-1826
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• 2002

• Journal of Microbiology and Biotechnology
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• v.9 no.5
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• pp.646-649
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• 1999

A thermophilic bacterium producing D-stereospecific dipeptidase was isolated from Korean soil samples. The enzyme hydrolyzed the peptide bond between D-alanyl-D-alanine (D-Ala-D-Ala). The isolated bacterial strain was rod shaped, gram-positive, motile, and formed an endospore. Morphological and physiological characteristics suggested this microorganism a thermophilic Bacillus species, and was named as Bacillus sp. BCS-l. The production of D-stereospecific dipeptidase was growth-associated and optimal at $55^{\circ}C$. The enzyme was applied for the synthesis of D-amino acid-containing peptide, N-benzyloxycarbonyl-L-aspartyl-D-alanine benzyl ester (Z-L-Asp-D-AlaOBzl), as a model reaction. A thermodynamically controlled synthesis of Z-L-Asp-D-AlaOBzl was achieved in an organic solvent.

• Korean Journal of Pharmacognosy
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• v.17 no.1
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• pp.67-72
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• 1986

A stereospecific synthesis of 3-methyl-5-(1-hydroxy-4-oxo-2,6,6-trimethyl-2-cyclohexen-1-yl)-cis, trans-2,4-pentadienoic acid (abscisic acid) from ${\alpha}-ionone$ has been investigated. Ethyl 5-(2,6,6-trimetyl-2-cyclohexen-1-yl)-trans-4-penten-2-ynoate $({\alpha},{\beta}-acetylenic\;ester)$, which was synthesized from alpha-ionone in two steps, was stereospecifically converted in good yield into ethyl 3-methyl-5-(2,6,6-trimethyl-2-cyclohexen-1-yl)-cis, trans-2, 4-pentadienoate $({\alpha}-ionylideneacetate)$ by the conjugate addition of lithium dimethylcuprate at $-78^{\circ}C$. Basic hydrolysis of the ethyl ${\alpha}-ionylideneacetate$ gave an abscisic acid precursor, 3-methyl-5-(2,6,6-trimethyl-2-cyclohexen-1-yl)-cis, trans-2,4-pentadienoic acid, which can be oxidized to yield abscisic acid.

• Journal of Microbiology and Biotechnology
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• v.10 no.5
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• pp.573-579
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• 2000

Knowledge on the enzymes acting on p-amino-acid-containing peptides appears to be somewhat limited when compared with those acting on peptides composed on L-amino acids. Less than ten D-stereospecific enzymes are hitherto known. This review describes about several novel D-stereospecific peptidases and amidases of microbial origin, including D-aminopeptidase (E.C. 3.4.11.19), alkaline D-peptidase, and D-amino aicd amidase, which are applied to the synthesis of D-amino acid/or D-amino acid derivatives.

• Bulletin of the Korean Chemical Society
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• v.6 no.2
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• pp.95-98
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• 1985

Stereospecific [2 + 2] cycloadducts are obtained as major products when trans-cinnamonitrile derivatives are irradiated with excess tetramethylethylene. The fluorescence quenching studies, weak exciplex fluorescence, and sensitization by benzophenone suggest that this stereospecific photochemical cycloaddition reaction involves singlet exciplex intermediate formed between cinnamonitrile derivatives and tetramethylethylene.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.625-628
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• 2001

To isolate novel strains that hydrolyzed the rac-ketoprofen ethyl ester to ketoprofen in the stereospecific manner, we screened broad ecological niches and soil samples in which the activity was expected to be found. From thousands of strains, we isolated a Pseudomonas sp. S34 producing a (S)-stereospecific esterase, and a thermostable esterase with (R)-form selectivity was also 。 btained from Bacillus stearothermophilus JYl44. To further analyse the gene structure and to induce a high level expression, two genes from each strain were cloned and sequenced. BLAST search results with the esterase gene from 534 revealed that both of gene (80-84 %) and amino acid sequences (89- 95 %) were highly conserved in the related esterases from Pseudomonas strains (fluorescens and aeruginosa). The thermostable esterase from JY144, however, revealed a relative low homology (45-52 %) to other esterase and/or lipase from related strains. Obviously, a complete conversion with pure enantiomer (R - or S) were readily achieved by recombinant clones expressing either (R)- or (S)- stereospecific esterase.

• Bulletin of the Korean Chemical Society
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• v.17 no.5
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• pp.468-470
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• 1996

• Journal of the Korean Chemical Society
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• v.52 no.5
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• pp.588-592
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• 2008

• Bulletin of the Korean Chemical Society
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• v.6 no.2
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• pp.119-120
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• 1985

Stereospecific coordination of racemic 2,3-diaminobutane has been observed in the reaction with platinum(Ⅱ) complexes of optically active 6,6'-dimethyl-2,2'-diaminobiphenyl. The reaction between [Pt (R-dmdabp) Cl$_{2}$] (R-dmdabp is R-6,6'-dimethyl-2,2'-diaminobiphenyl) and unresolved bn (bn is 2,3-diaminobutane) has yielded [Pt(R-dmdabp)-(R-bn)] Cl$_{2}$ only, while the reaction of [Pt(S-dmdabp)Cl$_{2}$] with unresolvd bn has yielded [Pt(S-dmdabp) (S-bn)]Cl$_{2}$ only. On the other hand, the standard [Pt(R-dmdabp) (R-bn)] Cl$_{2}$ complex has been independently prepared from the reaction of [Pt(R-dmdabp)Cl$_{2}$] with R-bn, and the standard [Pt(S-dmdabp) (S-bn)] Cl$_{2}$ from the reaction of [Pt(S-dmdabp)Cl$_{2}$] with S-bn. The stereospecific behavior of the racemic 2,3-diamino-butane is thus confirmed from the comparison of these Pt(Ⅱ) complexes prepared using racemic bn with the standard Pt(Ⅱ) complexes prepared using R-bn or S-bn.