• Archives of Pharmacal Research
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• 제22권4호
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• pp.335-339
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• 1999

The oxidation-reduction potentials of cosmetic raw materials, showing tyrosinase inhibitory action, and phenolic compounds structurally similar to L-tyrosine were determined by cylcic voltammetry. The voltammograms obtained could be classified ito 4 patterns (patterns 1-4). Patterns 1, characterized by oxidation and reduction peaks as a pair, was observed with catechol, hydroquinone or phenol, and pattern 2 exhibiting another oxidation peak in addition to oxidation and reduction peaks as a pair was found with arbutin, kojic acid, resorcinol, methyl p-hydroxybenzoate and L-tyrosine as the substrate of tyrosinase. Pattern 3 with an independent oxidation peak only was expressed by L-ascorbic acid, and pattern 4 with a reduction peak only at high potentials, by hinokitiol. The tyrosinase inhibitory activity of these compounds was also evaluated using the 50% inhibitory concentration ($IC_{50}$) and the inhibition constant (Ki) as parameters. Hinokitiol, classified as patterns 4, showed the highest inhibitory activity (lowest $IC_{50}$ and Ki). Hydroquinone showing the second highest activity belonged to pattern 1, which also included compounds exhibiting pattern 2 was relatively low with Ki values being in the order of 10-4 M. Although there was no consistent relationship between oxidation-reduction potentials and tyrosinase inhibitory action, the voltammetry data can be used as an additional index to establish the relationship between the structure and the tyrosine inhibitory activity.

• 한국환경농학회지
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• 제35권3호
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• pp.216-222
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• 2016

Polychlorinated biphenyl은 잔류성 환경 오염물질로서, 다양한 생리 독성 때문에 인축에 대한 세부적 연구가 수행된 바 있다. 한편 포유동물을 대상으로 진행된 연구에서 hydroxy PCBs, PCB quinones, 및 methylsulfonyl PCBs 등의 대사물이 발견되었으며, 이들은 모화합물과는 상이한 독성을 나타낸다고 보고되었다. 그러나 이와 같은 동물에 대한 연구와 비교하여, 식물 및 토양 미생물에 대한 영향, 독성 등에 대한 연구는 매우 제한적이다. 일반적으로 식물의 경우, 농약 등과 같은 외래 물질 또는 자외선, 병원균 등의 외래 스트레스원의 작용을 받게되면, 특이 생물활성을 지닌 파이토알렉신 등의 이차 대사산물을 생합성하는 것이 알려져 있다. 본 연구에서는 수 종의 PCB 및 hydroxy PCB, phenol류 등을 화학적으로 합성하고, 이들의 처리에 따른 당근 중, 파이토알렉신인 6-메톡시멜레인 생합성에 미치는 영향을 검토하였다. 증류수를 처리한 대조구의 경우, 파이토알렉신의 농도는 처리 후 2일에 최대치까지 증가하였으며, 이후 지속적으로 감소하였다. 한편 2-hydroxy/4-hydroxybiphenyl의 경우, 처리 후 3일까지 증대한 반면, 비교적 지용성이 높은 PCB-126 및 3,5-dichloro-2-hydroxybiphenyl 처리구에서는 처리 1일 후, 최대치를 나타내어 화합물의 구조 또는 지용성 등에 따라 다른 유도효과를 나타내었다. 이상의 결과에 따라, 환경 오염물질의 성상에 따라, 토양 중, 재배 농작물의 생리 활성 2차 대사물질의 생합성이 다양하게 변화됨을 알 수 있었다.

• Environmental Analysis Health and Toxicology
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• 제17권1호
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• pp.37-51
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• 2002

Eleven phenols including two chlorophenols, eight alkylphenols and bisphenol A were derivatized with isobutylchloroformate to form their isobutoxycarbonyl derivatives. Standard phenol mixture was concentrated for the isobutoxycarbonyl (isoBOC) derivatization and analysed by gas chromatography/mass spectrometry (GC/MS). The recoveries of the derivatization method of alkylphenols, chlorophenols, and bisphenol A were calculated by gas chromatography/mass spectrometry-selected ion monitoring mode using two work-up methods for comparison; shaking and heating method. The linear detector responses were obtained in the concentration range of 5∼400 ng, with correlation coefficients varying from 0.9755∼0.9981. Recoveries of the alkylphenols, chlorophenols, and bisphenol A were determined by gas chromatography/mass spectrometry-selected ion monitoring mode using two work-up methods for comparison ; the US-EPA method and the isoBOC derivatization method, Eleven phenols in water samples were extracted with dichloromethane and then concentrated. Also, solid-phase extraction (SPE) with XAD-4 and subsequent conversion to isobutoxycarbonyl derivatives for sensitive analysis with the selected ion-monitoring (SIM) mode. The recoveries were 85.1∼109.9％ and 90.3∼126.6％ for the US-EPA method and the isoBOC.

• 대한화학회지
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• 제56권3호
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• pp.357-362
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• 2012

5-Nonylsalicylaldoxime and salicylaldehyde are two derivatives of phenolic compounds which are very applicable materials in industries. Formerly the formylation of phenolic derivatives were carried out by Rimer-Tiemann method. In this work both of these two materials were synthesized by magnesium meditated formylation technique and their structural characterizations were compared by instrumental analysis technique. In order to achieve a selectively orthoformylated product, the hydroxyl group of nonylphenol (or phenol) was first modified by magnesium methoxide. The nonylphenol magnesium salt was then formylated by paraformaldehyde. The oximation reaction was finally applied to the prepared nonylsalicylaldehyde magnesium salt by liquid extracting via water and acid washing and other extractions. The solvent was finally removed by evaporation under reduced pressure. Some instrumental analysis such as $^1H$-NMR, GC/MS and FT-IR spectra were taken on the product in order to interpret the reaction characterization quantitatively and qualitatively. The formaldehyde and oxime functional groups of two compounds were investigated through $^1H$-NMR and FT-IR spectra and were compared. The yield of methoxilation was very good and the yields of formylation and oximation reactions were about 90%and 85% respectively. The orthoselectivity of formylation reaction were evaluated by comparing of the relevant spectra. The GC/MS spectra also confirmed the obtained results.

• Korean Chemical Engineering Research
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• 제54권5호
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• pp.687-692
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• 2016

바이오매스는 대체 에너지원으로서 재생가능하고 전 세계적으로 고르게 분포하고 있으며, 친환경적이고 탄소중립적이어서 많은 관심을 받고 있다. 굴참나무를 대상으로 바이오에너지 생산의 효용성을 알아보기 위해 기포 유동층 반응기를 이용하여 급속 열분해반응 특성 연구를 수행하였다. 반응 온도에 변화에 따른 생성물의 수율 변화를 확인하기 위해 $400{\sim}550^{\circ}C$의 온도범위에서 급속 열분해반응 실험을 진행하였고, 이때 바이오-오일의 수율은 36.98~39.14 wt%, 가스의 수율은 33.40~36.96 wt%의 값을 나타내었다. 바이오-오일의 발열량은 $500^{\circ}C$, $3.0{\times}U_{mf}$ 조건에서 20.18 MJ/kg을 나타내었다. 생성된 열분해 가스의 주 생성물은 $CO_2$, CO 및 $CH_4$이며 $CO_2$의 선택성이 37.16~50.94 mol%로 가장 높았다. 바이오-오일은 푸르푸랄, 페놀과 이들의 유도체인 1-hydroxy-2-propanone, 2-methoxy-phenol, 1,2-benzendiol, 2,6-dimethoxy-phenol에 대한 높은 선택성을 가지고 있었다.

• 대한화장품학회지
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• 제35권4호
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• pp.271-276
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• 2009

기질 화합물로써 일련의 4-($R_1$)-benzyl alcohol 및 4-($R_2$)-phenol 유도체들의 치환기($R_1$ 및 $R_2$)가 변화함에 따른 tyrosinase 활성저해에 관한 3차원적인 구조-활성 상관 (3D-QSARs) 모델을 유도하고 정량적으로 검토하였다. 그 결과, 입체장, 정전기장, 소수성장 및 수소결합 주게장의 조합조건에서 통계적으로 양호한 CoMSIA 2 모델(상관성; $r^2\;=\;0.858$ 및 예측성; $q^2\;=\;0.951$)을 유도하였다. 등고도 분석결과, 기질분자의 $R_2$-치환기는 입체적으로 작고 음전하를 띄며, 소수성이면서 수소결합 주게장을 선호하지 않는 치환기가, 그리고 $R_1$-치환기는 양전하를 띄며 수소결합 주게장을 선호하는 치환기가 tyrosinase의 저해활성이 증가 될 것으로 예상되었으며, 수소결합 받게장은 전혀 영향을 미치지 않았다.

• Bulletin of the Korean Chemical Society
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• 제24권4호
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• pp.460-466
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• 2003

For the drug master file (DMF) of ketoconazole, four impurities (1-4) contained in ketoconazole were synthesized. During the synthesis of 2, a new synthetic method of 1,4-dihydropyrazine was established. To oxidize the aminoalcohol (2j) to the aminal (2j-1), the standard Swern oxidation condition was modified to mask the nucleophilicity of the amino group temporarily using one equivalent of acetic acid. Derivative 3 was synthesized via regioselective bromination at the 2 position of the 4-aminophenol derivative (3a) using $Br_2$ in the presence of p-TsOH. The etherification of aryl bromide with the phenol derivative (1f) was accomplished by a modification of the general Cu-mediated reaction condition using excess 1f itself as a solvent at elevated temperature (190 ℃).

• Bulletin of the Korean Chemical Society
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• 제32권5호
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• pp.1599-1603
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• 2011

Novel chemosensors based on 2-(2'-hydroxyphenyl)quinoline were prepared and evaluated for sensing metal cations. The photophysical properties of chemosensors 1-3 were examined and their ion-selectivity was evaluated by measuring their fluorescent emission responses to alkali, alkaline earth, and transition metal ions. Chemosensors 1, 2 and 3 show ratiometric and enhanced fluorescence changes with transitional metals that are efficient fluorescence quenchers, especially 3 has a high binding constant with $Hg^{+2}$ in $CH_3CN$.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.378-378
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• 2006

The preparation, characterization, and bio-testing of biocide incorporated silicone coatings for marine applications have been conducted. Derivatives of the biocide, Triclosan (5-chloro-2-(2, 4-dichlorophenoxy) phenol), were used to covalently attach the biocide moiety to a silicone backbone. The synthetic process allowed for control of the resulting coating's mechanical properties as well as antifouling/fouling release performance in laboratory and ocean site testing. The test results showed significantly reduce macro fouling with sustained fouling release characteristics for the coatings produced.

• 대한화학회지
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• 제16권5호
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• pp.320-327
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• 1972

韓國産 土炭의 흄酸의 性狀(分子量, 分子式 및 示性式)과 基應用(田沓用 土壤改良制 및 溶性燐質 肥料製造)에 關해서 이미 硏究報韓 바가 있으나, 흄酸의 構造를 推定하는데 있어서, 未及한 鮎이 있어서, 이의 補完策으로서 aromatic diazonium salt를 coupling 시켜, phenolic-OH group 의 結合狀態를 살펴보고 各種 aromatic diazonium salt와 흄酸 및 니트로흄酸에 依해서 얻어진 生成物들을 Azo 染料로 利用함으로서 應用策의 一環을 講究했다.