• 한국산업융합학회 논문집
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• 제6권2호
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• pp.109-113
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• 2003

We report herein synthetic results obtained new types of crown ethers containing coumarin group. Crown ethers containing coumarin group 1~3 are hydroxymethyl-15-crown-5-ether linked with 4-hydroxy coumarin-4-acetic acid by esterification reaction. Crown ethers containing coumarin group 1~3 have different cavity in each crown ether rings. The 12-crown-4 ether with coumarin 1 has the smallest cavity size. The 15-crown-5 ether with coumarine 2 has the medium cavity size. The 18-crown-6 ether with coumarin 3 has the largest cavity size. Therefore each crown ether with coumarin group will recognize different ionic radius meta. Because of different hole size in crown ethers, these crown ethers seem to be had different selectivity in luminescent sensors. The crown ethers with coumarine 1~3 synthesized hydroxymethyl-15-crown-5-ether and 4-hydroxy coumarin-4-acetic acid same ratio at one to one. The synthesized crown ethers were characterized respectively by IR, NMR. GC-Mass.

• Elastomers and Composites
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• 제45권4호
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• pp.286-290
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• 2010

Coumarin기가 포함된 액정성을 가진 단량체를 액정 상태에서 UV 조사에 의해 중합하였다. Cycloaddition 반응에 의해 coumarin 액정 단량체는 이량체로 전환되었으며, 광이량화 반응 후에도 액정성이 유지되었다. 그리고 이러한 이량체는 단량체의 액정범위 보다 넓은 영역에서 액정성을 나타내었다. 화합물의 구조는 FT IR 및 $^1H$ NMR에 의해 확인하였으며, 그들의 열적 상전이온도 및 열안정성들은 DSC, GPC 및 편광현미경에 의해 조사하였다. 광중합에 의해 생성된 고분자 생성물은 광학 편광 현미경 관찰에 의해 스멕틱 및 네마틱 조직을 갖는 쌍방성 액정성을 보였다.

• 분석과학
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• 제18권1호
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• pp.89-95
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• 2005

Studies on the electrochemical reduction of 7-acetoxy-4-bromomethyl-coumarin (ABMC), 7-acetoxymethyl coumarin (AMC), and coumarin in 0.1 M tetraethyl ammonium perchlorate acetonitrile solution were carried out with direct current, differential pulse polarography, cyclic voltammetry, and controlled potential coulometry. The electrochemical reduction of ABMC was proceeded through three irreversible steps coupled with the chemical reactions. The solution color was changed to yellow when the carbonyl group was reduced during second step and the color change was independent with bromo group of ABMC. Fluorescent intensity was highest when the electrochemical reduction was controlled at near the overpotential of supporting electrolyte (-2.3 volts).

• Bulletin of the Korean Chemical Society
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• 제35권7호
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• pp.2183-2185
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• 2014

• 분석과학
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• 제8권4호
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• pp.655-661
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• 1995

The electrochemical reduction of coumarin derivatives in 0.1M TEAP acetonitrile solution was investigated by the direct current, differential pulse polarography, cyclic voltammetry and controlled potential coulometry. The electrochemical reduction of 7-acetoxy-4-bromomethyl-coumarin(ABMC) was proceeded as an irreversible three steps(-0.58, -1.63 and -2.25 volts) of electrochemical transfer before chemical reaction. The solution color turned to yellow after the carboxyl group was reduced at 2nd step(-1.63 volts vs. Ag-AgCl) and the change in color was independant to the bromo group. Upon the basis of the results on the products analysis and the interpretaton of polarograms, a possible electrochemical reaction mechanism was suggested.

• Bulletin of the Korean Chemical Society
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• 제27권9호
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• pp.1329-1334
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• 2006

The electrochemical reduction of coumarin, 7-acetoxy-4-methyl coumarin (AMC), and 7-acetoxy-4-bromomethyl coumarin (ABMC), in 0.1 M tetraethyl ammonium perchlorate/acetonitrile solution was carried out by direct current, differential pulse polarography, cyclic voltammetry, and controlled potential coulometry. The electrochemical reduction of ABMC was proceeded through three steps of electron transfer coupled with the chemical reactions. The color of solution was changed to yellow when the carbonyl group was reduced during 2nd step (-1.8 volts) and independented with cleavage of bromo group. Highest fluorescence intensity showed when the electrochemical reduction of AMC was controlled at near the potential (-2.3 volts vs. Ag/AgCl).

• Macromolecular Research
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• 제12권6호
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• pp.615-617
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• 2004

We have developed an efficient method for the generation of patterned fluorescence images using a protected precursor molecule. The t-Boc-protecting group of a coumarin derivative was readily removed from a polymer film upon irradiation with UV light in the presence of a photoacid generator to provide the original properties of the coumarin. Fine fluorescence patterns were obtained when using this photolithographic method.

• Bulletin of the Korean Chemical Society
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• 제22권2호
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• pp.179-182
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• 2001

Photocyclizable poly(cinnam-4'-yl methyl methacrylate) derivatives bearing methoxy benzene (PMCMMA), anthracene (PACMMA), and coumarin (PCCMMA) have been synthesized via Heck type reaction. Three different types of polymers are photoreactable usin g linearly polarized UV light and applicable as liquid crystal alignment layer. Anthracence and coumarin containing polymers (PACMMA, PCCMMA) have better thermal stability than PMCMMA. This observation may be attributed to the glass transition temperature elevation due to the bulky size and another photocrosslinking site provided by anthracene or coumarin group.

• Elastomers and Composites
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• 제44권4호
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• pp.416-422
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• 2009

Benzyl 4-Hydroxybenzoate와 1,6-Dibromohexane을 반응시켜 4-(6-bromohexyloxy)benzoic acid를 합성하였다. 이것을 하이드로퀴논과 반응시켜 브롬 그룹을 갖는 새로운 mesogenic ester를 합성하였다. Mesogenic ester를 자외선에 민감한 coumarin과 반응시켜 새로운 형태의 광응답성 coumarin 화합물을 합성 하였다. 합성된 화합물의 구조는 FT-IR 및 $^1H$-NMR에 의해 확인 하였으며, 그들의 열적 상전이온도 및 안정성들은 DSC, 편광현미경 및 X-선 회절에 의해 조사 하였다. 한편 합성된 새로운 화합물은 광학 편광 현미경 관찰에 의해 스멕틱 및 네마틱 구조를 갖는 쌍방성 액정성을 보였다.

• 분석과학
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• 제5권1호
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• pp.83-90
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• 1992

$^{14}C$-warfarin을 흰쥐에 경구투여 후 4시간 경과시 혈액에서 최고치를 나타내었으며, coumarin과 그 유도체인 warfarin에 의한 간조직 microsome 내의 Cyt. p-450은 이들 화합물에 의해 microsomal electron transport system이 증가됨과 Cyt. p-450의 isozyme들이 유도됨을 확인할 수 있었다.