• Journal of Microbiology and Biotechnology
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• 제15권5호
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• pp.1106-1109
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• 2005

The antimicrobial effect of the wood vinegar of C. japanica sapwood and its constituents was evaluated against Ralstonia salanacearum, Phytophthora capsid, Fusarium oxysporum, and Pythium splendens. Phenols and guaiacols had a strong antimicrobial effect against four kinds of microorganisms, but methanol and acetic acid exhibited little or no antimicrobial activity.

• 약학회지
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• 제55권3호
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• pp.273-276
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• 2011

Synthetic studies directed toward an ortho-fluorination of phenols are described. With eugenol as the test compound, effects of base, fluorination agents, and solvents on ortho-fluorination has been investigated.

• Bulletin of the Korean Chemical Society
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• 제31권11호
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• pp.3395-3398
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• 2010

• Bulletin of the Korean Chemical Society
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• 제29권4호
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• pp.876-878
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• 2008

• Bulletin of the Korean Chemical Society
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• 제30권5호
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• pp.1071-1076
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• 2009

N,N,N′,N′-tetramethylethylenediamine (TMEDA) acts as a simple, mild and efficient catalyst for the acylation of alcohols, phenols and thiols at room temperature under solvent-free condition. Acylation reaction with acetic anhydride and benzoic anhydride proceeds with good to excellent yield in the presence of TMEDA as the catalyst.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.68.1-68.1
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• 2003

A method for determination 11 endocrine disrupting chemicals of phenols in various samples was deloped. The alkylphenols, chlorophenols and bisphenol A were determined by gas chromatography/mass spectrometry-selected ion monitoring (GC/MS-SIM) followed by two work-up methods for comparison; isobutoxycarbonyl (isoBOC) derivatization method and tert-butyldimethylsilyl (TBDMS) derivatization method. Eleven endocrine disrupting chemicals (EDCs) of phenols in biological samples were extracted with acetonitrile and then acetonitrile layer was refrigerated at -60$^{\circ}C$ for 2 hours (freezing filtration). (omitted)

• Bulletin of the Korean Chemical Society
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• 제26권12호
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• pp.2007-2016
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• 2005

An artificial neural network (ANN) is successfully presented for prediction acidity constant (pKa) of various benzoic acids and phenols with diverse chemical structures using a nonlinear quantitative structure-property relationship. A three-layered feed forward ANN with back-propagation of error was generated using six molecular descriptors appearing in the multi-parameter linear regression (MLR) model. The polarizability term $(\pi_1)$, most positive charge of acidic hydrogen atom $(q^+)$, molecular weight (MW), most negative charge of the acidic oxygen atom $(q^-)$, the hydrogen-bond accepting ability $(\epsilon_B)$ and partial charge weighted topological electronic (PCWTE) descriptors are inputs and its output is pKa. It was found that properly selected and trained neural network with 205 compounds could fairly represent dependence of the acidity constant on molecular descriptors. For evaluation of the predictive power of the generated ANN, an optimized network was applied for prediction pKa values of 37 compounds in the prediction set, which were not used in the optimization procedure. Squared correlation coefficient $(R^2)$ and root mean square error (RMSE) of 0.9147 and 0.9388 for prediction set by the MLR model should be compared with the values of 0.9939 and 0.2575 by the ANN model. These improvements are due to the fact that acidity constant of benzoic acids and phenols in water shows nonlinear correlations with the molecular descriptors.

• 한국산림과학회지
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• 제99권2호
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• pp.226-234
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• 2010

This study was conducted to examine the effects of pruning season on the compartmentalization of pruning wounds in Acer palmatum and Pinus strobus. A total of eighty five field-grown trees for each species were allocated to five different seasons, early- and late-winter, mid-spring, mid- and late-summer, for pruning treatments. Wound closure rate (WCR) of the two species for one year after treatment, area of discolored stem tissue on the medial longitudinal surface and cambial dieback length under the pruning wound of A. palmatum were measured. Changes of total phenols and variations of extractives, holocellulose and lignin at the treated branch unions were examined. In WCR of A. palmatum, late-winter (March, 39.8%) and mid-spring (May, 39.7%) were higher than any other seasons, while early-winter (November, 28.4%) was significantly lower than late-winter and mid-spring. P. strobus showed similar results with A. palmatum. The WCR of early-winter (57.2%) was the lowest significantly among the five seasons, and mid-spring (73.5%) and late-winter (71.4%) showed higher a WCR than other seasons. In the discolored/wound area ratio of A. palmatum, early-winter (73.2%) was the highest by far, and mid- (July) and latesummer (September, 36.7%, respectively) were the lowest among the five seasons. In the length of cambial dieback, two dormant seasons, early- and late-winter were longer than any other seasons. Phenol contents at the treated branch union were changed in line with the seasonal fluctuation of the tree. Total phenols in the below core of the treated union were higher than those of the branch union with living branch, while little differences were seen in the above core. At the branch core of the treated union, phenols of A. palmatum decreased one month after the treatments, but P. strobus maintained similar to or a little higher than those at the controls. The major changes in chemical composition at pruning wounds were extractives and lignin increased by less than 20% in A. palmatum, while extractives in P. strobus remarkably increased by 70%.

• Applied Biological Chemistry
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• 제31권3호
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• pp.292-297
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• 1988

토마토 과실의 향기성분을 생체흡착법, 파쇄흡착법 및 연속 수증기증류법으로 추출하고 GC와 GC-MS에 의해 동정하였다. 생체흡착법으로 추출한 향기성분은 80여 종 이상이 분리되었고 그 중 alcohols 10종, aldehydes 6종, ester 3종, ketones 4종, phenol 1종, acid 1종으로 총 25종을 동정하였다. 파쇄흡착법으로 추출한 향기성분은 100여종 이상이 분리되었고 그중 alcohols 12종, aldehydes 6종, Ketones 5종, esters 5종, phenols 2종, hydrocarbon 1종, acid 1종으로 총 32종이 동정되었다. 연속수증기증류법으로는 향기성분 300여종 이상을 분리하였고 그 중 alcohols 19종, ester 9종, hydrocarbons 13종, aldehydes 8종, Ketones 9종, phenols 2종, lactones 2종, furans 2종, acid 1종, oters 2종으로 총 67종이 동정되었다. 연속수증기 증류법에 의해 동정한 성분 중 아직까지 MS에 의해 동정되지 않은 성분들은 hydrocarbons 11종, aldehydes, Ketones 및 other 각각 2종, alcohol, ester, lacton 및 furfural 각각 1종으로 총 21종이었다.

• 대한화학회지
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• 제30권4호
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• pp.352-358
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• 1986

페놀류의 머무름 거동에 대한 실험적 관찰을 이성분용매인 MeOH-Water, ACN-Water, THF-Water와 삼성분용매인 MeOH-Water, ACN-Water, THF-Water계에서 수행했다. 이 머무름 거동의 데이타들로써 용매의 성분비에 따른 크기인자를 예측할 수 있는 선형방정식을 얻었다. 또 페놀류의 최적 분리에 적합한 MeOH-Water이성분 용매를 기준하여 이론적으로 용매세기가 같은 이성분과 삼성분용매를 사용했고 이 등용매세기하에서 시료에 대한 머무름 거동의 특이성 효과는 이성분용매계가 삼성분용매계보다 더 크게 나타났다.