• Title/Summary/Keyword: Phenol derivatives

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Relationship Between Tyrosinase Inhibitory Action and Oxidation-Reduction Potential of Cosmetic Whitening Ingredients and Phenol Derivatives

  • Sakuma, Katsuya;Ogawa, Masayuki;Sugibayashi, Kenji;Yamada, Koh-ichi;Yamamoto, Katsumi
    • Archives of Pharmacal Research
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    • v.22 no.4
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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.

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Effects of Polychlorinated Biphenyls and Phenols on the Biosynthesis of 6-Methoxymellein, a Phytoalexin (당근 Phytoalexin 6-Methoxymellein 생합성에 미치는 Polychlorinated Biphenyls 및 Phenol의 영향)

  • Lim, Do-Hyung;Lim, Da-Som;Keum, Young-Soo
    • Korean Journal of Environmental Agriculture
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    • v.35 no.3
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    • pp.216-222
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    • 2016
  • BACKGROUND: Polychlorinated biphenyls (PCBs) are one of the most common environmental contaminants. Because of their recalcitrant properties and long-term toxicity, numerous studies have been performed. The toxicological concerns are focused on endocrinological effects of animal. Several different metabolites have been reported, including hydroxy PCBs, PCB quinones, and methylsulfonyl PCBs from animal tissues. However, details in plants have never been studied. It is well-known that plants can produce phytoalexin in response to chemical, physical, or pathological stress.METHODS AND RESULTS: In this study, the several PCBs and hydroxy derivatives were prepared by chemical syntheses. Their effects on secondary metabolite biosynthesis were determined in carrot roots. The levels of 6-methoxymellein were determined in several different treatments, using gas chromatography-mass spectrometry. In general, the concentration of 6-methoxymellein reached a maximum at 2 days and gradually decreased to trace level at 5 days in control experiments. However, the effects of PCBs or hydroxy derivatives were highly dependent on compounds. For example, the maximum concentrations of 6-methoxymellein were observed at 3 days for 2-hydroxy/4-hydroxybiphenyl, while 3,3',4,4',5-pentachlorobiphenyl and 3,5-dichloro-2-hydroxybiphenyl showed a rapid accumulation within 1 day, followed by rapid dissipation to undetectable levels.CONCLUSION: Biphenyl derivatives were effective elicitor of 6-methoxymellein accumulation. In general, hydroxybiphenyls (phenols) more efficiently induced phytoalexin biosynthesis than those without hydroxy groups. It can be concluded that PCBs or their possible metabolites could change the plant secondary metabolism.

Application and Optimization of the IsoButoxycarbonyl Derivatization method to the Analysis of Trace Level Phenols in Environmental Samples (환경시료로부터 미량 페놀류의 분석을 위한 isoButoxycarbonyl 유도체화 분석방법 적용 및 최적화)

  • Kim, Hyub;Hong, Jong-Ki;Kim, Yong-Hwa;Kim, Kyoung-Rae
    • Environmental Analysis Health and Toxicology
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    • v.17 no.1
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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.

Comparing of 5-Nonylsalicylaldoxime and Salicylaldehyde Characterization Using Magnesium Salt Formylation Process

  • Pouramini, Zeinab;Moradi, Ali
    • Journal of the Korean Chemical Society
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    • v.56 no.3
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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.

Pyrolysis of Quercus Variabilis in a Bubbling Fluidized Bed Reactor (기포 유동층 반응기에서 굴참나무의 열분해반응 특성 연구)

  • Lim, Dong-Hyeon;Sim, Jae-Wook;Kim, Seung-Soo;Kim, Jinsoo
    • Korean Chemical Engineering Research
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    • v.54 no.5
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    • pp.687-692
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    • 2016
  • Biomass has been concerned as one of the alternative energy resources because it is renewable, abundant worldwide, eco-friendly, and carbon neutral. Quercus variabilis has been studied to understand pyrolysis reaction characteristics, and to evaluate the efficiency of bio-energy production from fast pyrolysis. Quercus variabilis were fast pyrolyzed in a bubbling fluidized bed reactor at various reaction conditions. The effects of pyrolysis temperature between $400^{\circ}C$ and $550^{\circ}C$ on product yields were investigated. The yield of bio-oil was changed between 36.98 wt% and 39.14 wt%, and those of gas yield was 33.40 and 36.96 wt% with increasing reaction temperature. The higher heating value (HHV) of bio-oil at $500^{\circ}C$ ($3.0{\times}U_{mf}$) was 20.18 MJ/kg. The gas compositions were similar for all reaction conditions such as CO, $CO_2$ and $CH_4$, and $CO_2$ selectivity was the highest (37.16~50.94 mol%). The bio-oil has high selectivities for furfural, phenol and their derivatives such as 1-hydroxy-2-propanone, 2-methoxy-phenol, 1,2-benzendiol, 2,6-dimethoxy-phenol.

3D-QSAR Analyses on the Inhibition Activity of 4-($R_1$)-Benzyl Alcohol and 4-($R_2$)-Phenol Analogues Against Tyrosinase (4-($R_1$)-Benzyl alcohol 및 4-($R_2$)-Phenol 유도체들의 Tyrosinase 활성 저해에 대한 3D-QSAR 분석)

  • Kim, Sang-Jin;Lee, Myoung-Hee
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.35 no.4
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    • pp.271-276
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    • 2009
  • The 3-dimensional quantitative structure-activity relationships (3D-QSARs) models between the substituents with changing groups ($R_1$ & $R_2$) of 4-($R_1$)-benzyl alcohol and 4-($R_2$)-phenol derivatives as substrate molecule and their inhibitory activities against tyrosinase were derived and discussed quantitatively. The optimized CoMSIA 2 model have best predictability and fitness ($r^2\;=\;0.858$ & $q^2\;=\;0.951$). The contour maps of optimized CoMSIA 2 model showed that, the inhibitory activities of the analogues against tyrosinase were expected to increase when hydrophobic favor, negative charge favor, steric disfavor and hydrogen bond donor disfavor groups were substituted at the $R^2$ position. When the positive charge and the hydrogen bond donor favor groups were substituted at the $R_1$ position, it is predicted that the substituents will be able to increase the inhibitory activity. However, hydrogen bond acceptor did not affect inhibitory activities of tyrosinase.

Synthesis of Ketoconazole Derivatives

  • Ryu, Jae-Chun;Lee, Kwang-Jae;Lee, Sang-Hee
    • Bulletin of the Korean Chemical Society
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    • v.24 no.4
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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 ℃).

Fluorescence Sensing Properties of 2-(2'-Hydroxyphenyl)quinoline and Derivatives

  • Helal, Aasif;Lee, Sang-Hoon;Ren, Wen Xiu;Cho, Chan-Sik;Kim, Hong-Seok
    • Bulletin of the Korean Chemical Society
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    • v.32 no.5
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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 $CH_3CN$.

SILICONE POLYMER FOR ANTIFOULING/FOULING RELEASE MARINE COATING APPLICATION

  • Choi, Seok-Bong;Jepperson, John;Thomas, Johnson;Jarabek, Laura;Chisholm, Bret;Boudjouk, Philip
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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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.

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Studies on the Characteristics of Humic Acid and its Utilizations (Part 4). Manufacturing of Azo-dyes from Humic Acid (土炭흄酸의 性狀 및 應用에 關한 硏究 (第4報) 아조染料 製造에 관하여)

  • Han Kyoungsuk;Kim, Won Taek
    • Journal of the Korean Chemical Society
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    • v.16 no.5
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    • pp.320-327
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    • 1972
  • The coupling of aromatic diazonium salts with humic or nitrohumic acid, as a supplemental method of determining the structure and utilization of humic acid, were studied. The following results were obtained. 1) Humic acids have many vacan to-and p-positions in their phenol kernels. 2) Humic acids have not so many benzene kernels in their structure units. 3) When coupled with aromatic diazonium salts (such as aniline, aminonaphthalene and aminoanthraquinone derivatives), various azo-dye were obtained.

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