• Bulletin of the Korean Chemical Society
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• 제23권12호
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• pp.1715-1718
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• 2002

Treatment of ethyl 5-hydroxy-3,4-diphenylthieno[2,3-c]pyridazine-6-carboxylate (1a) with hydrazine hydrate in ethanol gave the carbohydrazide 2,. Some derivatives of the latter compound have been synthesized. Also, 6-acetyl-3,4-diphenyl-5-hydroxythieno[2.3-c]pyridazine (1b) was subjected to some reactions to produce other new thienopyridazine derivatives.

• 대한화학회지
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• 제58권5호
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• pp.450-455
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• 2014

In the present study, a series of novel N-(1H-benzo[d]imidazol-2-yl)methyl-5-[(hetero)aryl-1,3,4-oxadiazol-2-yl]methanamine (4a-4j) were efficiently synthesized. Condensation of hydrazide derivative 3 with various carboxylic acid derivatives yielded N-[(1H-benzo[d]imidazol-2-yl)methy](5-substituted-1,3,4-oxadiazol-2-yl)methanamine (4a-4j) and compound 5-{[(1H-benzo[d]imidazol-2-yl)methylamino]methyl}-1,3,4-oxadiazole-2-thiol (4k) was obtained on treating hydrazide 3 with carbon disulfide. All the newly synthesized analogues were characterized by IR, $^1H$ NMR, $^{13}C$ NMR and mass spectral data.

• 대한화학회지
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• 제53권2호
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• pp.159-165
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• 2009

2-Amino-5-Substituted-1,3,4-Oxadiazoles의 합성은 비분활된 셀에서 포텐셜 전기분해의 제어하에 백금전극의 세미카바존 전기적 산화로부터 수행되었다. 이것은 유기화학 합성분야에서 환경적으로 양호한 방법이다. 아세트산 및 아세트니트릴, 무수용매와 리튬 과염소산염 이 전기적 산화에서 전기분해을 위하여 사용 되어졌다. 생성물은 IR, $^1H$-NMR, $^{13}C$-NMR 그리고 원소분석을 통해 구조분석 하였다.

• 공업화학
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• 제17권3호
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• pp.286-290
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• 2006

새로운 4급 염화 암모늄염, {alkyldimethyl-[5-(2-phenylthiazol-4-yl]-1,3,4-oxadiazol-2-ylmethyl]quaternary ammonium chlorides (ADOQACs): 6}을 화합물 5와 몇 가지 N,N-dimethylalkyl amine을 반응시켜 합성하였다. 합성한 화합물들의 구조와 물리적 특성을 조사하였고 계면활성을 측정하였다. 화합물 6의 표면장력($\gamma_{cmc}$)과 최소저해농도(MIC)는 알킬기의 영향을 받은 것으로 나타났으며, 특히 화합물 6c와 6d가 좋은 항균력과 계면활성을 보였다.

• 전자공학회논문지D
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• 제35D권11호
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• pp.55-61
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• 1998

정공 전달 중합체인 Poly(N-vinylcarbazole) (PVK)와 전자전달 유기물 재료인 2-(4-biphenyl)-5-(t-butyl-phenyl)-1,3,4-oxadiazole (Bu-PBD)에 발광 유기물 색소 Coumurine 6, TPB, Rhodamine B를 각각 도핑한 단층박막 유기물 전기발광 소자를 제작하였다. 스핀 코팅 방법에 의한 단층 구조와 가용성 재료의 사용으로부터 소자제작이 간단하였다. 활성영역은 인듐주석산화물(ITO) 과 알루미늄 전극 사이에 놓인 단층으로 구성하고 있다. 이러한 구조에서 전자와 정공의 전하가 각 전극에서 PVK : Bu-PBD 활성층으로 주입된다. 전압을 인가한 후 발광된 빛의 색은 각각 TPB, C6, Rhodamine B의 유기물 색소에 의해 481nm, 500nm, 585nm 파장을 갖는 푸른색, 초록색 및 오렌지색을 나타내었다. PVK유기물은 다른 발광색을 갖는 유기물 색소를 분자 적으로 도핑 함으로서 주요한 중합체로서 사용될 수 있다. 그리고 전기발광색은 전체 가시광선 파장 내로 조절될 수 있다.

• Macromolecular Research
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• 제15권3호
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• pp.216-220
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• 2007

A new polyfluorene-based copolymer having 2-ethylhexyloxy-5-methoxy-l,4-phenylene as an electron donating group and 2,5-diphenyl-oxadiazole as an electron withdrawing group was synthesized by the Suzuki coupling reaction. The obtained copolymer was characterized by $^1H-NMR,\;^{13}C-NMR$, and IR-spectroscopy. The weight average molecular weight ($M_w$) of the obtained polymer was 18,600 with a polydispersity index of 1.5. The maximum photoluminescence of the solution and film of the polymer was observed at 453 nm and 456 nm, respectively. A double-layer device with the configuration, ITO/PEDOT/copolymer/Al, emitted blue light at 460 nm.

• Journal of Photoscience
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• 제4권3호
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• pp.97-103
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• 1997

The effect of temperature on the fluorescence quenching of 2-(4-Methoxyphenyl)-5-(1-naphthyl)-1,3,4-oxadiazole (MPNO1), 2-(4-Methoxyphenyl)-5-(2-naphthyl)-1,3,4-oxadiazote(MPNO2), by aniline, and 2-Phenylindole (2-PI) by CCk, in toluene by steady state method and in benzene by time-resolved method have been carried out in the temperature range 30 - 70$\circ$C. The Stem-Volmer (S-V) plots, I$_0$/I against quencher concentration [Q] at different temperanares show positive deviations. The fluorescence lifetimes determined at different temperatures show no systematic variations and the variations being within the experimental error, the average values of lifetimes $ $\tau$ (t) are taken for further calculations. Rate constants such as Stem-Volmer quenching constants K$_sv}$, quenching rate parameters k$_q$ and k'$_q$, static quenching constant V and kinetic distance r are determined using the modified Stem-Volmer equation and sphere of action static quenching model. In order to see whether the reactions are diffusion limited, equations k$_q$ = e$^{-Eq/RT}$ and k'$_q$ = e$^{-Eq/RT}$ are used to determine the values of E$_q$ and E'$_q$, the activation energies for collisional quenching and the values of E$_q$ are 14.53. 17.28 and 16.20 kJ mole$^{-1}$ for MPNO1, MPNO2 and 2-PI respectively and the values of E'$_q$ are 14.62 and 17.73 for MPNO1 and MPNO2 respectively. From the magnitudes of various quantities it has been concluded that the reactions are diffusion limited and the observed positive deviations in the S-V plot are due to static and dynamic quenching.

• 동의생리병리학회지
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• 제23권2호
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• pp.389-396
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• 2009

The ethanol extract of Persicaria perfoliata (EPP) induced relaxation of the phenylephrine-precontracted aorta in a dose-dependent manner, which was abolished by removal of functional endothelium. Pretreatment of the aortic tissues with NG-nitro-L-arginine methyl ester (L-NAME) or 1H-[1,2,4}-oxadiazole-[4,3-${\alpha}$)-quinixalin-1-one (ODQ) inhibited the relaxation induced by EPP. However, EPP-induced relaxation was not blocked by pretreatment with indomethacine, glibenclamide, tetraethylammonium (TEA), atropine, or propranolol. Incubation of endothelium-intact thoracic aortic ring with EPP increased the production of cGMP, which was also blocked by pretreatment with L-NAME or ODQ. These results suggest that EPP dilates vascular smooth muscle via endothelium-dependent NO/cGMP signaling.

• Journal of Photoscience
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• 제6권4호
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• pp.159-163
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• 1999

The fluorescence quenching of 2-phenyl-5-(4-biphenylyl)-1,3,4-oxadiazole (PBD) and 1,4-di-[2-(5-phenyloxazolyl)]-benzene (POPOP) by aniline has been carried out in different solvent mixtures of dioxane and acetonitrile at room temperature. The quenching is found to be appreciable and a positive deviation from linearity was observed in the Stern-Volmer plot in all the solvent mixtures. Various rate constants for the quenching processes have been determined using a modified Stern-Volmer equation. From the positive deviations of linear Stern-Volmer plots and the dependence of rate constants on the polarity of the solvents, it has been concluded that both static and dynamic quenching processes are responsible for the observed positive deviation in the Stern-Volmer plot.

• 동의생리병리학회지
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• 제19권3호
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• pp.797-801
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• 2005

While conducting an in vitro screening of various medicinal plant extracts, an aqueous extract of Rosa rugosa Radix (ARR) was found to exhibit a distinct vasorelaxant activity. ARR induced a concentration-dependent relaxation of the phenylephrine-precontracted aorta. This effect disappeared with the removal of functional endothelium. Pretreatment of the aortic tissues with NG-nitro-L-arginine methyl ester (L-NAME) or 1H-[1,2,4]-oxadiazole-[4,3-]-quinoxalin-1-one (ODQ) completely inhibited the relaxation induced by ARR. ARR-induced vascular relaxations were also markedly attenuated by addition of diltiazem or verapamil. However, the relaxant effect of ARR was not blocked by pretreatment with indomethacine, tetraethylammonium (TEA), glibenclamide, atropine, or propranolol. Taken together, the present study suggests that ARR dilates vascular smooth muscle via endothelium-dependent NO/cGMP signaling.