• Bulletin of the Korean Chemical Society
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• 제11권3호
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• pp.194-200
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• 1990

Various mechanistic aspects of the A2 hydrolysis of methyl acetimidate were explored using the MNDO method. As in thecorresponding reactions of acetamide and methyl carbamate, a proton transfer pre-equilibrium exists between the N-protonated and the O-protonated tautomers, and the subsequent hydrolysis proceeds from the more stable N-protonated form. Of the two reaction pathways, the $A_{AL}2$ path is favored in the gas phase and in concentrated acid solutions, whereas the $A_{AC}2$ path is favored in less acidic solutions with a stable cationic tetrahedral intermediate formed in the rate determining step. Negative charge development on the alkoxy oxygen in the transition state suggested a rate increase with the increase in the electron withdrawing power of the alkoxy group. Calculations on the reaction processes with AM1 indicated that MNDO is more reliable in this type of work, although AM1 is better than MNDO in reproducing hydrogen bonds.

• Bulletin of the Korean Chemical Society
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• 제34권4호
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• pp.1237-1239
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• 2013

• 대한약학회:학술대회논문집
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• 대한약학회 2000년도 NEW STRATEGY FOR DRUG DEVELOPMENT IN POST-GENOMIC ERA(대한약학회)
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• pp.213.3-214
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• 2000

• Bulletin of the Korean Chemical Society
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• 제22권8호
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• pp.793-794
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• 2001

• Bulletin of the Korean Chemical Society
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• 제18권3호
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• pp.344-347
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• 1997

• 한국산학기술학회논문지
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• 제11권10호
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• pp.4041-4046
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• 2010

유연한 알콕시 곁사슬을 갖는 전방향족 폴리에스터가 direct polycondensation에 의하여 합성되었으며, 합성된 중합체들은 $^1H$-NMR, FT-IR, DSC, TGA, 편광현미경 및 X-ray 분석기에 의하여 조사되었다. 1,1,2,2-테트라클로로에탄(TCE)을 용매로 사용하여 측정된 중합체의 고유점성도(${\eta}_{inh}$)는 0.46~2.41 dL/g의 값을 나타내었다. 곁사슬을 갖는 중합체들은 두 개의 용융전이 즉, 고체상-sanidic 액정상으로의 전이 ($T_{m1}$)와 sanidic 액정상-nematic 액정상으로의 전이 ($T_{m2}$)를 나타내었으며, 알콕시 곁사슬의 길이가 증가함에 따라 상전이온도들은 감소하고, 유기용매에 의한 용해도는 증가하는 경향을 나타내었다. X-ray 분석에서, $2{\theta}\;{\simeq}5$와 $2{\theta}\;{\simeq}20$ 피이크는 각각 중합체 주사슬과 긴 곁사슬의 결정화에 의한 것으로 나타났다.

• 한국식품영양과학회지
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• 제34권10호
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• pp.1503-1508
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• 2005

본 연구에서는 대식세포인 RAW 264.7 세포주에 SQ ($0.1{\%}$), AG($0.1{\%}$), Batyl(1 mg/mL), Chimyl(1 mg/mL) 용액 등을 단독 혹은 C. albicans와 함께 첨가하여 배양한 후LDH, NO, TNF-$\alpha$, IL-6 발현에 어떤 영향을 주는 지를 관찰하였다. 모든 실험군에서 실험에 사용한 농도는 LDH, NO생산에 영향을 주지 못하였다. 실험에 사용한 용액을 단독 처리한 실험의 경우 TNF-$\alpha$와 IL-6발현의 경우 6시간째에는 큰 차이를 나타내지는 못하였으나, 24시간째에는 발현에 영향을 주었다(p < 0.05). C. albicans을 함께 처리한 실험의 경우에는 C. albicans단독 처리군에 비해 실험 용액을 함께 처리한 군에서 C. albicans유도 TNF-$\alpha$와 IL-6발현을 감소시키는 효과를 관찰하였다(p < 0.05, p < 0.01). 본 연구를 통해 SQ, AG, Batyl, Chimyl 용액이 C. albicans 유도에 의해 감소된 면역반응을 증가시킬 수 있을 것으로 생각되어진다.

• 대한화학회지
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• 제45권4호
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• pp.386-390
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• 2001

• Bulletin of the Korean Chemical Society
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• 제31권2호
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• pp.447-452
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• 2010

A series of 5-alkoxy-tetrazolo[1,5-a]quinolines were synthesized to evaluate their anticonvulsant and antidepressant effects. Anticonvulsant effects and neurotoxicity of the compounds when injected intraperitoneally to mice were determined by a maximal electroshock (MES) test and a rotarod test, respectively. Only three of the synthesized compounds (4a, 4b, 4c) displayed anticonvulsant activity at a dose of 300 mg/kg. Most of the compounds significantly reduced immobility times during the forced swimming test (FST) at a dose of 100 mg/kg, indicative of antidepressant activity. Among the compounds, 5-(2-fluorobenzyloxy)tetrazolo[1,5-a]quinoline (4k) reduced immobility time by 66.85% at 30 mg/kg compared with the same dose of Fluoxetine, which reduced immobility time by 52.30%. According to the results of the 5-Hydroxytryptophan induced head-twitch test and yohimbine toxicity potentiation test, the noradrenergic system seems not to be involved in the antidepressant-like effect of compound 4k while the serotonergic system seems a little to be involved.

• ETRI Journal
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• 제27권2호
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• pp.181-187
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• 2005

Alkoxy-substituted poly(spirobifluorene)s and their copolymers with a triphenylamine derivative have been synthesized by Ni(0)-mediated polymerization. The polymers were well soluble in common organic solvents. Pure blue-light emissions without the long wavelength emission of poly(fluorene)s have been observed in the fluorescence spectra of polymer thin films. The light emitting diodes with a device configuration of ITO/PEDT:PSS(30 nm)/polymer(60 nm)/LiF(1 nm)/Al(100 nm) have been fabricated. The electroluminescence spectra showed the blue emissions without the long wavelength emission as observed in the fluorescence spectra. The relatively poor electroluminescence quantum yield of the homopolymer (0.017% @ 20 $mA/cm^{2}$) with color coordinates of (0.16, 0.07) has been improved by the introduction of triphenylamine moiety, and the copolymer with derivative exhibited an electroluminescence quantum yield of 0.15 % at 20 $mA/cm^{2}$ with color coordinates of (0.16, 0.08). Moreover, the introduction of polar side chains to the spirobifluorene moiety enhanced the device performance and led to the quantum yields of 0.6 to 0.7 % at 20 $mA/cm^{2}$, although there was some expense of color purities.