• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.486-489
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• 2011

Potassium dihydrogen phosphate was found to be an efficient catalyst for the Pechmann condensation of phenols with ethyl acetoacetate, leading to the formation of coumarins under microwave-irradiation and solvent-free condition. This procedure offers several advantages, including the low loading of catalysts, high yields, clean reactions, short reaction time for the synthesis of coumarins.

• Journal of the Korean Chemical Society
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• v.20 no.3
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• pp.236-239
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• 1976

The mechanism of skin-sensitizing photoreactions of coumarins and furocoumarins are studied by spectroscopic, triplet quenching, and fluorescence techniques. The excited singlet mechanism is suggested for xanthotoxin-thymine/or DNA photoreactions from the results of triplet quenching studies utilizing ${\beta}$-carotene as a quencher.

• Korean Chemical Engineering Research
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• v.51 no.1
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• pp.157-161
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• 2013

Low priced and environment-friendly natural dye from coumarin- containing plants for the dye sensitized solar cell (DSSC) was developed. Dyes were extracted from cinnamon and angelica that contained coumarin derivatives, and DSSCs employing these dyes were prepared. PV efficiency of 0.75% was obtained from cinnamon dye, which is comparable to the highest efficiency reported in precedent studies about natural dye DSSC. It was confirmed by UV-visible and FT-IR spectroscopy that coumarin derivatives in the plants acted as photosensitive material.

• Journal of the Korean Applied Science and Technology
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• v.29 no.4
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• pp.610-617
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• 2012

Trifoliate orange components consist of several kinds, such as monoterpenes, limonoids, flavonoids, and coumarins. Coumarin derivatives were shown to possess valuable pharmacological properties such as anti-inflammatory and dietary effect. Among them, 7-geranyloxycoumarin 6 is a promising chemopreventive agent againist skin, tongue, oesophaqus and colon carcinogenesis in rodents. Seven new coumarin derivatives structurally related to 7-geranyloxycoumarin were synthesised in good yields by $Cs_2CO_3$/acetonitrile condition. We investigated the effect of anti-inflammatory activity on interleukin-6 for synthesised geranyloxycoumarin derivatives. 6-Geranyoxycoumarin 9 (68.9% / $1{\mu}M$ ; 72.6% / $10{\mu}M$) of the anti-inflammatory activity is far higher than 7-Geranyloxycoumarin 5 (40.1% / $1{\mu}M$ ; 61.1% / $10{\mu}M$) and their other derivatives.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2016.10a
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• pp.147-147
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• 2016

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2016.10a
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• pp.148-148
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• 2016

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2016.10a
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• pp.133-133
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• 2016

• Journal of the Korean Society of Tobacco Science
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• v.4 no.2
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• pp.63-66
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• 1982

Coumarin was pyrolyzed at $500^{\circ}C$ in a stream of nitrogen. The pyrolyzates of coumarin were adsorbed on the activated charcoal and then eluded by carbon disulfide. The eluted pyrolyzates were identified using a gas chromatography/mass spectrometry. Benzene, toluene, phenylacetylene, styrene, benzofuran and naphthalene were detected from the pyrolyzates of coumarin on the basis of their mass spectra. The pyrolytic mechanism of coumarin was also discussed.

• Journal of the Korean Chemical Society
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• v.55 no.4
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• pp.662-665
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• 2011

Highly efficient, three-component condensation of aromatic aldehyde, malononitrile and 4-hydroxycoumarin promoted by neat silica gel at room temperature is described. The method offers an excellent alternative to the synthesis of 3,4-dihydropyrano[c]chromenes. The reactions are fast and clean, and the products are obtained with good yield and purity.

• YAKHAK HOEJI
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• v.54 no.5
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• pp.416-421
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• 2010

We examined whether indomethacin, noscapine, coumarin, uridine and betaine affect airway mucin production induced by EGF or TNF-${\alpha}$ from NCI-H292 cells. Cells were pretreated with each agent for 30 min and then stimulated with EGF or TNF-${\alpha}$ for 24 h. Of the five compounds, coumarin suppressed airway mucin production induced by EGF or TNF-${\alpha}$. However, indomethacin suppressed airway mucin production induced by EGF. This result suggests that coumarin and indomethacin can regulate the production of mucin induced by EGF, by directly acting on airway epithelial cells.