• Archives of Pharmacal Research
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• 제12권2호
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• pp.68-72
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• 1989

The hydrolysis rates of ester and amide derivatives of 20-dihydroprednisolonic acid were measured in rat serum and liver homogenate. The hydrolysis rate of the esters in serum was found to be faster than that in liver homogenate on the basis of blood volume and liver weight, while the amide derivatives showed much slower change. And it is also found that the size of substituents at C-21 and C-20 configuration expressed considerable effects on the hydrolysis rate of these derivatives.

• 대한화학회지
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• 제24권6호
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• pp.457-462
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• 1980

Phosphoryl chloride와 allyl alcohol, 2,3-dibromopropanol, 2-pyrrolidone, ethylenimine을 반응하여 여러가지 phosphate와 phospshoric amide를 합성하였다. 합성한 화합물은 모두 열에 불안정하였으며, allyl phosphorodichloridate와 diallyl phosphorochloridate는 증류하면 상당량의 중합체가 생겼다. IR 스펙트라에서는 $1,300∼1,200 cm^{-1}$에서 P=O stretching의 특성밴드가 나타났으며 NMR 스펙트라는 인원자의 long range coupling 효과로 인해 복잡한 피이크를 보였다. 2,3-dibromopropyl phosphordichloridate의 mass 스펙트럼에서는 분자이온 피이크를 볼 수 없었다.

• 대한화학회지
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• 제51권4호
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• pp.361-364
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• 2007

Microwave irradiation하에서 황산 실리카를 사용한 케톤에서 아미드의 합성을 관한 one-pot Beckmann자리옮김 반응에 대한 보고이다. 산과 케톤의 몰비율이 1:2인 이 방법의 장점은 간단한 조작과 짧은 반응시간으로 높은 수율을 가진 위치선택적 반응이고, 최근에 사용되었던 방법보다 더 친환경적이다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권4호
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• pp.244-251
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• 2001

Over half of all biologically active peptide and peptide hormones are $\alpha$-amidated at their C-terminus, which is essential for their full biological activities. Amidation is accomplished through the sequential reaction of the two enzymes encoded by the single bifunctional, peptidyl-glycine $\alpha$-amidating monooxygenase (PAM or an $\alpha$-amidating enzyme). PAM catalyze the forma - tion of a peptide amide from peptide precursors that include a C-terminal glycine, and requires copper molecular oxygen and ascorbate. PAM is the only enzyme that produces peptide amides in vivo. However various strategies utilizing PAM, carboxypeptidase-Y enzymes, and chemical syn-thesis have been developed for producing peptide amides in vitro. The growing need and impor-tance of peptide amide drugs has highlighted the necessity for a efficient in vitro amidating sys-tem for industrial application for the production of peptide hormones, like calcitonin and oxytocin. This review presents the current situation regarding amidation with a special emphasis on the in-dustrial production or peptide hormones.

• Journal of Microbiology and Biotechnology
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• 제8권4호
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• pp.347-352
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• 1998

A new strain of Pseudomonas aeruginosa growing in a rice field contaminated with herbicide and effluents of a factory manufacturing explosives was isolated. This isolate showed excellent growth in unusually high concentration of acrylamide (60 mM). It utilized acrylamide as the sole source of carbon and nitrogen for growth. Other amides such as acetamide, butyramide, isobutyramide, and methacrylamide were also utilized for the growth by this isolate. Acrylamide was degraded into acrylic acid and ammonia by the enzyme amidase. More than $65\%$ of added acrylamide (40 mM) was converted into acrylic acid after 40 h of growth of the culture. Amidase activity was inducible, the highest activity being observed with isobutyramide ($12.5{\mu}M$ ammonia/mg protein/min). These results demonstrate that this bacterium can degrade a variety of amides.

• 약학회지
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• 제34권2호
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• pp.80-87
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• 1990

3-Substituted 5-aminoisoxazole-4-carboxylates were prepared by the reaction of corresponding bormoaldoximes with cyanoacetate. The 3-trifluoromethylisoxazole derivatives were acylated to amides with various aminopyridine derivatives to afford diamides. The ester group was hydrolyzed and decarboxylated easily to give 3-trifluoromethyl-5-aminoisoxazole. The aminoisoxazole was also converted to amides. 5-Amino-3-trifluoromethylisoxazole-5-one-4-carboxylate was prepared by the reaction of trifluoroacetoaldoximoyl bromide and malonate. 5-Amino-3-methylisoxazole-5-one-4-acetate was prepared by the reaction of hydroxylamine and acetylmalonate. The synthesized compounds were tested for antiinflammatory activities.

• Journal of Microbiology and Biotechnology
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• 제20권3호
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• pp.622-629
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• 2010

Biosynthetic studies on brasiliamides, potently convulsive and bacteriostatic compounds from an endophytic Penicillium brasilianum isolated from Melia azedarach (Meliaceae), confirms their phenylpropanoid origin, which is very uncommon in fungi. Feeding experiments with [$2-^{13}C$]-phenylalanine indicated the incorporation of two units of this amino acid on brasiliamide structures. The first step in the phenylpropanoid pathway to those compounds was evaluated through enzymatic bioassays and confirmed the phenylalanine ammonia-lyase (PAL) participation. The metabolism of phenylalanine in this fungus is discussed.

• Bulletin of the Korean Chemical Society
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• 제14권6호
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• pp.743-749
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• 1993

The approximate rates and stoichiometry of the reaction of excess lithium tris(dihexylamino)aluminum hydride(LTDHA) with selected organic compounds containing representative functional groups under the standardized conditions (tetrahydrofuran, 0$^{\circ}$C) were studied in order to define the reducing characteristics of the reagent for selective reductions. The reducing ability of LTDHA was also compared with those of the parent lithium aluminum hydride(LAH), lithium tris(diethylamino)aluminum hydride(LTDEA), and lithium tris(dibutylamino)aluminum hydride(LTDBA). In general, the reactivity toward organic functionalities is in order of $LAH{\gg}LTDEA{\geq}LTDBA>LTDHA$. LTDHA shows a unique reducing characteristics. Thus, the reagent reduces aldehydes, ketones, esters, epoxides, and tertiary amides readily. Anthraquinone is cleanly reduced to 9,10-dihydro-9,10-anthracenediol without hydrogen evolution, whereas p-benzoquinone in inert to LTDHA. In addition to that, disulfides are also readily reduced to thiols without hydrogen evolution. However, carboxylic acids, anhydrides, nitriles, and primary amides are reduced slowly. Especially, this reagent reduces aromatic nitriles to the corresponding aldehydes in good yields.

• Bulletin of the Korean Chemical Society
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• 제12권6호
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• pp.612-617
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• 1991

The approximate rates and stoichiometry of the reaction of excess 1,3,2-biphenyldioxaborepin [2,2'-biphenoxyborane (BPB)] with selected organic compounds containing representative functional groups under the standardized conditions (tetrahydrofuran, hydride to compound being 4 : 1, room temperature) was examined in order to define the characteristics of the reagent for selective reductions and compare its reducing power with those of other substituted boranes. The results indicate that BPB is unique and the reducing power is much stronger than that of other dialkoxyboranes, such as catecholborane and di-s-butoxyborane. BPB reduces aldehydes, ketones, quinones, lactones, tertiary amides, and sulfoxides readily. Carboxylic acids, anhydrides, esters, and nitriles are also reduced slowly. However, the reactions of acid chlorides, epoxides, primary amides, nitro compounds, and disulfides with this reagent proceed only sluggishly.

• Bulletin of the Korean Chemical Society
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• 제12권6호
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• pp.644-649
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• 1991

The approximate rates and stoichiometry of the reaction of excess lithium tris(dibutylamino)aluminum hydride (LT-DBA) with selected organic compounds containing representative functional groups under standardized conditions (tetrahydrofuran, $0^{\circ}C$) were studied in order to characterize the reducing characteristics of the reagent for selective reductions. The reducing ability of LTDBA was also compared with those of the parent lithium aluminum hydride and the alkoxy derivatives. The reagent appears to be much milder than the parent reagent, but stronger than lithium tri-t-butoxyaluminohydride in reducing strength. LTDBA shows a unique reducing characteristics. Thus, the reagent reduces aldehydes, ketones, esters, acid chlorides, epoxides, and amides readily. In addition to that, ${\alpha},{\beta}$-unsaturated aldehyde is reduced to ${\alpha},{\beta}$-unsaturated alcohol. Quinones are reduced to the corresponding diols without evolution of hydrogen. Tertiary amides and aromatic nitriles are converted to aldehydes with a limiting amount of LTDBA. Finally, disulfides and sulfoxides are readily reduced to thiols and sulfides, respectively, without hydrogen evolution.