• 약학회지
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• 제37권3호
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• pp.228-234
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• 1993

A new series of 7-deazapurine derivatives[7,8] as purine antagonists was prepared. Diethyl 4-cyano-N-(diphenyimethylene)-3-arylglutamate[3] were synthesized by LDA-catalyzed Michael addition of N-(diphenylrnethylene)glycine ethyl ester with (E)-2-cyano-3-arylacrylate. Deprotection yields diethyl 4-cyano-3-arylglutamate, which were easily cyclized to 4-cyano-2-ethoxycarbonyl-5-oxo-3-arylpyrrolidine[4]. The compounds[4] were treated with NaBH$_{4}$ and then with (C$_{2}$H$_{5}$)$_{3}$OBF$_{4}$ to give 4-cyano-5-ethoxy-2H-2-ethoxymethyl-3-aryl-3,4-dihydropyrrole[6], which were converted to 7-aryl-6-amino-8-ethoxymethyl-7,8-dihydro-7(3H, 9H)-deazapurine-2-thione[7] and 7-aryl-2,6-diamino-8-ethoxymethyl-7,8-dihydro-7(9H)-deazapurine[8] with possible activity against neoplastic disease.

• 대한수의학회지
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• 제35권2호
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• pp.279-285
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• 1995

To characterize non-adrenergic non-cholinergic(NANC) nerve mediated contractile responses in circular smooth muscle of bovine reticular groove, we investigated NANC relaxation and contraction induced by electric field stimulation to enteric nerves. In the presence of atropine($1{\mu}M$) and guanethidine($50{\mu}M$), electric field stimulation at frequency of 1 to 16Hz(square pulses, 0.5ms duration, 70V) evoked clear-cut relaxations through stimulations. Transient 'rebound contraction' was occured when the stimulus was switched off. All of the responses (relaxation and rebound contraction) were dose-dependently blocked by Nw-nitro-$_{\small{L}}$-arginine methyl ester(L-NAME), an inhibitor of nitric oxide synthesis, and methylene blue, and inhibitor of soluble guanylate cyclase. Tetraethyl ammonium(TEA), a potassium channel blocker, did not block the NANC relaxations.

• 한국응용과학기술학회지
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• 제28권3호
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• pp.259-266
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• 2011

Caffeic acid is a kind of phytochemicals occurred in coffee, which is worked as a carcinogenesis restrainer and antioxidants on the human body. In this study, as one type of caffeic acid derivatives, methoxypolyethylene glycol caffeate(MPC) was synthesized by the esterification between caffeic acid and methoxypolyethylene glycol with N,N'-dicyclohexyl carbodiimide, 4-dimethylamino pyridine. The synthesized product was confirmed by using FT-IR and $^1H$-NMR, thin-layer chromatography. And these compound was investigated as antioxidant, Tyrosinase hindrance and skin moisturizers. In the free radical scavenging study, antioxidant effect of MPC was averagely high than the red ginseng extract that be used as a natural antioxidants. The result of Tyrosinase anti-activity test was better than embryo bud of rice extract at low concentration. At the iNOS anti-activity tested by using Raw 264.7 cell, and confirmed anti-inflammatory function. For the MPC handled with sodium lauryl sulfate, was tested for the skin moisture content and skin moisture loss.

• 한국군사과학기술학회지
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• 제12권5호
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• pp.660-666
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• 2009

Thermoplastic polyurethane elastomer(PU-TPE) and energetic thermoplastic polyurethane Elastomer(E-PU-TPE) were prepared from Hexamethylene diisocyanate(HDI), 1,4-BD/AA ester polyol and glycidyl azide polymer(GAP-2400) as an energetic material by the addition polymerization. The PU-TPE and E-PU-TPE were characterized by FT-IR and GPC. Viscometer, DSC and UTM were used to investigate the viscose behavior with a various solvent, thermal properties and mechanical properties of PU-TPE and E-PU-TPE, which are of potential interest for the development of high performance binder of energetic solid propellants. It was found that $M_w$ of PU-TPE and E-PU-TPEs are over 100,000 and decreased with increase of GAP-2400 contents. $T_m$ and ${\Delta}H$ as thermal properties decreased and also tensile strength and elongation at break as mechanical properties decreased with increase of GAP-2400 contents.

• 대한화학회지
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• 제43권5호
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• pp.535-539
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• 1999

Timmis반응을 이용하여 1,3-dimthyllumazine유도체를 합성하였다. 4-Amino-1,3-dimethyl-5-nitrosouracil(1)을 2,4-pentanedione, ethyl cyanoacetate, 그리고 ethyl acetoacetat와 반응시켜 6-acetyl-1,3,7-trimethyllumazine (2), ethyl 7-amino-1,3-dimethyllumazine-6-carboxylate (4), ethyl 1,3,7-trimethyl-lumazine-6-carboxylate (5)를 좋은 수율로써 합성하였다. 화합물 2,4,5의 6-아세틸 및 에스테르기에 대한 곁사슬 반응으로 다양한 1,3-dimethyllumazine 유도체들이 합성되었다. 합성된 화합물의 구조 및 물리적 특성은 NMR, UV, IR스펙트럼, 그리고 원소분석에 의하여 확인하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.527-527
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• 2009

1세대 바이오디젤인 fatty acid methyl ester(FAME)의 문제점을 극복하기 위하여 많은 연구가 진행 중 이다. 소위 차세대 바이오디젤은 triglyceride의 산소 화합물을 제거하여 정유 공정을 통해 생산된 디젤과 동일한 특성을 지닌 탄화수소로 전환시킨 오일이다. 이를 위하여 수소를 첨가하여 산소를 제거 시키는 Hydrodeoxygenation(HDO) 반응이 필요하다. 고온($300-400^{\circ}C$), 고압(50-100 bar)의 혹독한 조건에서 높은 수율과 안정성을 보이는 촉매 개발이 필요하다. 이를 위하여 반응물중의 산소를 효과적으로 제거하기 위하여 산소 전달능이 뛰어난 $CeO_2$ 담체에 열안정성을 높이는 $ZrO_2$를 조합한 $Ce-ZrO_2$ 담체를 선정하였으며 수소첨가 탈산소 반응에 활성을 나타낼 것으로 예상되는 니켈을 활성성분으로 선정하였다. 본 연구에서는 15%Ni-$Ce_{(1-x)}Zr_{(x)}O_2$ ($0{\leq}x{\leq}1$)촉매를 공침법(co-precipitation)으로 제조하였으며 $500^{\circ}C$에서 소성하였다. 촉매 특성분석은 XRD, BET, H2-TPR을 이용하였다.

• Applied Biological Chemistry
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• 제39권4호
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• pp.309-314
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• 1996

2-Furyltriisopropoxytitanium은 chlorotaniumtriisopropoxide를 이용하여 2-furyllithium을 금속 전이(transmetallation)시킴으로써 합성되었다. 이 화합물은 실온에서 분리되고 수 주일 동안 $-10^{\circ}C$에서 보존할 수 있었다. 카르보닐 화합물에 대한 2-furyltriisopropoxytitanium의 반응성이 높다는 것을 알았다. 알데히드와 케톤 1:1 혼합물과의 경쟁 반응에서 이 화합물은 완벽한 알데히드 선택성을 나타내었다. 또한, 케톤과 케톤 1: 1 혼합물과의 경쟁반응에서도 이 화합물은 케톤-케톤 구별정도가 상당했다. 케톤-에스테르 작용기에 대한 반응에서 이 화합물은 단지 케톤기와만 반응하였다.

• 한국환경농학회지
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• 제34권4호
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• pp.345-349
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• 2015

BACKGROUND: In this study, we have attempted to identify a urinary biomarker to assess chlorpyrifos exposure in farmers. The major metabolite and the excretion pathway of chlorpyrifos is 3,5,6-trichloro-2-pyridinol (TCP) in urine. Herein, we describe an adequate synthetic method for TCP hapten for measuring urinary TCP of farmers. METHODS AND RESULTS: First, TCP was prepared by spacer attachment through hydrolysis of thiophosphate ester from chlorpyrifos. After reaction with benzyl bromide, the TCP was transformed into 2,3,5-trichloro-6-benzyloxypyridine. Next, the chlorine in the 2 ^nd position of the pyridyl ring was substituted into 3-mercaptopropanoic acid spacer arm. Finally, the phenyl group attached to the 6 ^th position in pyridyl ring was removed for producing the targeted product, 3-(3,5-Dichloro-6-hydroxy-2-pyridyl) thiopropanoic acid. CONCLUSION: Henceforth, this TCP hapten would be used in developing immunoassay studies for the detection and quantitation of urinary TCP of farmers.

• 공업화학
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• 제5권4호
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• pp.662-668
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• 1994

Photoresist로의 응용을 위하여 감광성 관능기를 가진 폴리머인 polyresorcinol-formaldehyde glycidyl ether의 cinnamoyl ester(RGEFC)를 제조하였다. RGEFC의 감광 특성은 노광 전후의 유기용매에 대한 용해도 차이로서 결정하였는데, 유리판상에 도포한 각종 시료를 제반조건하에서 노광한 다음, 도포시에 사용한 같은 용매에 담그어 잔막수득량을 계산하였다. 필름의 감도와 밀접한 관계를 가지는 수득량은 수지의 중합도, 증감제의 종류 및 첨가농도에 따라 좌우되었으며, 그 감도는 폴리머의 중합도에 의존되어 중합도가 커질수록 증가되었다. 사용된 증감제 중 RGEFC에 대한 가장 효과적인 증감제는 2, 6-dichloro-4-nitroaniline이었다.

• 한국응용과학기술학회지
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• 제20권2호
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• pp.141-147
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• 2003

Oxidized polyethylene wax is obtained by oxidation of polyethylene wax and it is composed of various chemicals, e.g., fatty acid, alcohol, ketone and ester. The application of oxidized polyethylene wax is determined by the composition of these chemical substances. In this basic study we observed the basic reaction parameters of time, temperature, oxygen concentration and catalysts on the oxidation reaction of low molecular weight polyethylene(PE wax) by analyzing the acid value, physical and chemical properties of oxidized PE wax to develop a new oxidation process. Acid values are increased with temperature increase in the rage of $150^{\circ}C^{\sim}180^{\circ}C$ but decreased beyond 190$^{\circ}C$. Acid values are also increased with oxygen concentration. As the oxidation reaction proceeds the molecular weight and softening points of oxidation products are decreased by cracking reaction, but the viscosities are increased. To observe the crystallinity of oxidation products SEM experiment was performed. To obtain a high acid-value product in a mild condition, we adopted free radical catalysts and the acid value of the product using catalyst was higher than the product obtained without catalyst in the same reaction condition. The effective initiators were dicumyl peroxide(DCPO), t-butylperoxy-2-ethyl hexanoate(HOPO) and benzoyl peroxide(BPO) having long half-life.