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      • Hofmann 전이 반응을 이용한 N-(L-Aspartyl)-1,1-Diaminoethane의 합성

        정대일,이용균,정일수,김윤영,김선영,박민수 東亞大學校 1998 東亞論叢 Vol.35 No.-

        Some retroisomeric peptide showed an agonistic or antagonistic effect of the parent peptides. So the studies on their synthesis and their structure-activity relationship are currently being investigated. In general, the synthesis of the retroisomeric peptide required N,N'-diacylated gem-diamino compound as an important synthetic intermediate, in which those diacylated group could be removed selectively in different condition. In connection with the development of facile synthetic method for retroisomeric peptide, we tried the synthesis of N-benzoyl-1. l-diaminoethane, intermediate of 1, 1-diaminoethane based Sweetener, from N-benzoyl alanine aimde 28 using improved Hofmann rearrangement as a key step. In this procedure, the N-benzoyl-N'-Cbz-1,1-diaminoethane 29 could be prepared in high yield without any bypreducts. And also this compound was converted to N-benzoyl-1, 1-diaminoethane 30 by hydrogenolysis successfully. From the above result, this method thought to be very convenient synthetic method for these N-acyl-l, l-diamino typed compounds, a intermediate of retroisomeric peptides. And also β-benzyl aspartate, another intermediate of these sweetener, could be prepared from aspartic acid via dibenzylation and selective hydrolysis.

      • Benzodiazepinone과 1,5-Benzodiazepine 유도체의 합성 연구

        정대일,이용균,박유미,최태원,정일수,김인식,김윤영 東亞大學校 1997 東亞論叢 Vol.34 No.-

        The reaction of o-phenylenediamine 5 with acrylic acid 11 in the presencce of P₂O5+H₃PO₄afforded benzodiazepinone 13 and pyridobenzodiazepinono 17. The reactions of o-phenylenediamine 5 with acrylic acid 11 in the presence of PPA or SiO₂afforded only benzodiazepinone 13. But the reaction of O-phenylenediamine 5 with acrylic acid 11 in the presence of acetonedicarboxylic acid 18 or acetonedicarboxylic acid 18 and PPA or acetonedicarboxylic acid 18 and SiO₂was respectively synthesized 2,4,4,-trimethyI-3H-5-hydro-1.5-benzodi-azepine 23 as new cyclic imine compound. We propose that formation of 2-(2`-imine)propyI-N-isopropylidene aniline proceed though 2-amino, N-isopropylidene aniline intermediate C and 2-(N-a-methylethyI) amino, N-isopropylidene aniline intermediate G. The reaction of o-phenylenediamine 5 with acetonedicarboxylic acid 18 in the presence of PPA or SiO₂or HCI gave 2,4,4-trimethyI-3H-5-hydro-1,5-benzodiazepine 23. Using acetone 19 instead of acetonedicarboxylic acid 18, the reaction of o-phenylenediamine 5 in the presence of PPA or SiO₂or acrylic acid 11 was synthesized 2,4,4-trimethyI-3H-5-hydro-1,5-benzodiazepine 23 as same product. And also the reaction of o-phenylenediamine 5 with acetone 19 and acrylic 11 in the presence of PPA or SiO₂was obtained 2,4,4-trimethyI-3H-5-hydro-1,5-benzodiazepine 23. In case of acetophenone 21 in stead of acceton 19, the reaction of o-phenylenediamine 5 in presence of PPA or SiO₂at 40~45℃ were obtained 2,4-diphenyI-4methyI-3H-5-hydro-1,5-benzodiazepine 24. The reaction of o-phenylenediamine 5 with crotonic acid 25 in the presence of PPA or P₂O5+H₃PO₄or SiO₂at 100~110℃ afforded respectively 4-methybenzodiazepinone 26 as 1:1 cycloadduct.

      • TiO₂를 이용한 프로필렌 가스의 광촉매 산화반응

        정대일,이동희,김용환,김현숙,이용균,박유미,최순규,김동현 동아대학교 환경문제연구소 2001 硏究報告 Vol.24 No.1

        Photocatalyzed degradation of propylene gas was carried out over precoated titanium dioxide(anatase) illuminated W light in a flow reactor. photocatalytic oxidation of propylene gas indicated high conversion rates (78.0%) to CO₂ gas. And photocatalytic oxidation of gas according to a fold, twofold, and threefold of titanium dioxide(anatase) respectively gave high conversion rate. The longer reaction time was, the higher conversion rate to CO₂ gas showed.

      • 1,2-Benzisothiazol-3-one-1,1-Dioxide 유도체의 합성

        정대일,정희철,변석인,이용균,박유미,최순규,한정태 東亞大學校附設基礎科學硏究所 2002 基礎科學硏究論文集 Vol.19 No.1

        사카린 유도체는 제초제, 항독성, 살균제 등에 광범위하게 연구되어져 오고 있다. 새로운 농략 활성을 가진 물질을 합성하기 위해 먼저 선도물질로 사카린 1을 산화, 염소화 시킨 3-chloro-1,2-benzisothiazol-1,1-dioxide(BID-CI) 2와2cholromethy-1,2-benzisohizol-3-one1,1-dioxide 4를 합성하였다. 선도물질, amines, imidazoles, trones등과 반응시켜 다음과 같은 물질들을 얻었다. ; 3-cyclohexylamino-1,2-benzisothiazol-1,1-dioxide 6, 3-furylamino-1,2-benzisothiazol-1,1-dioxide 8, 3-(3-imidazol)-1,2-benzisothiazol-1,1-dioxide 10, 3-(2-methy-3-imidazol)-1,2-benzisothaizol-1,1-dioxide 12, 2-(3-imidazol)methy-1-1,2-benzisothiazol-3-one-1,1-dioxide 13, and 2-(-3-imidazol)methyl- 1,2-benzisothiazol-1,1-dioxide 14.

      • 폴리우레탄 포움에 의한 방향족 니트로화합물의 흡착성에 관한 연구

        문영자,정용순,이대운 연세대학교 교육대학원 1982 연세교육과학 Vol.21 No.-

        방향족 니트로화합물의 open-pore polyurethane foam(OPP foam)에 의한 흡착성에 영향을 미치는 여러가지 인자 즉 진탕시간, 용액의 pH, 시료분자의 이온화상수, 유기용매의 농도 등에 따른 분포계수(Kd)를 측정함으로써 분자구조와 관련하여 검토하였으며 흡착현상을 AmberiteXAD-2수지에 대한 흡착과 비교하여 그 흡착메카니즘을 규명하였다. 니트로유기화합물은 benzene, benzoic acid, aniline, phenol의 유도체이며 8-hydro-xyquinoline도 아울러 시도하여 보았다. OPP foam에 대한 방향족 니트로화합물의 기본흡착은 분자흡착이며 이들 분자와 OPP foam메트릭스사이의 반텔바알스인력과, OPP foam의 작용기와 시료의 작용기와의 쌍극자-쌍극자 및 수소결합에 기인하는 것 같다. OPP foam에 대한 방향족 니트로화합물들의 흡착력은 일반적으로 시료분자의 분자량 증가 및 소수성의정도가 클수록 강하고, 중성분자상태에서 최고가 되고 온도가 증가하고, 유기용매의 농도가 증가할수록 흡착이 감소되었다. 또한 시료의 극성 및 이온화상수가 클수록, pKa가 작을수록 Kd값은 감소되었다. 한편 OPP foam에는 tri-n-butylphosphate(TBP)와 같은 가소제(plasticizer)가 쉽게 침윤되므로 TBP-OPP foam을 사용하면 유기화합물의 Kd값을 OPP foam 만의 Kd값보다 크게 증가시킬 수 있으며 OPP foam에 의한 금속이온의 흡착 및 제거실험법으로 그 응용이 가능하다. The adsorption behaviors of nitro compounds of benzene, benzoic acid, phenol, aniline and 8-hydroxyquinoline (8-HQ) have been investigated. Distribution coefficients have been determined by batch method to study absorption mechanism of nitro compounds on open-pore polyurethane foam (OPP foam) by changing pH, methanol percentage of the medium. The adsorption behaviors of the aromatic nitro compounds on OPP foam are likely due to van der Waal's attraction between the organic molecule and foam matrix, as well as due to hydrogen bond and dipole-dipole interaction between the functional groups of organic molecule and hydroxy or amide group of foam matrix. OPP foam and XAD-2 have shown the following. similar adsorption behaviors for nitro compounds ; Adsorption of organic compounds is molecular adsorption. Distribution coefficients decreased with increasing methanol percentage of the medium. Nitro compounds which have more hydrophobic group have larger distribution coefficient than that of more hydrophilic group.

      • Alum응집제를 이용한 도시하수의 처리

        김용대 서강정보대학 1991 論文集 Vol.10 No.-

        When the sewage suspension was coagulated with Alum, the study on the effects of coagulant quantity, mixing time and mixing intensity was conducted. The results of this study were as follows. 1. The residual turbidity, pH, COD, and alkalinity value decreased as the coagulant quantity increased. 2. The residual turbidity, COD and alkalinity value decreased as mixing intensity and mixing time increased, but when mixing intensity was more than 300rpm and mixing time was more than 180sec, the residual turbidity, and COD increased little by little. 3. The pH value hardly varied regardless of mixing intensity and mixing time.

      • 3-Cyano 및 3-Carbomethoxy Chromone과 Allenylstannane과의 반응

        鄭大一,宋有淨,崔舜圭,李龍均,安賢淑,윤구식 東亞大學校附設基礎科學硏究所 1998 基礎科學硏究論文集 Vol.15 No.2

        t-Butyldimethylsilyl triflate 존재에서 3-Cyano 및 3-Carbomethoxy Chromone(1a,b)과 Allenylstannane(2) 과의 반응에서 Chromone의 C-2위치에 propargyl기가 도입된 유도체(3a,b)를 합성하였다. 합성한 유도체의 상대적 구조는 ¹H-NMR을 통해 분석하였으며, T.S구조의 모델을 통하여 가능한 메카니즘을 제시하였다. Reaction of 3-Cyano and 3-Carbomethoxy Chromone(1a,b) with Allenylstannane(2) in the presence of tert-butyldimethylsilyl triflate afforded the corresponding the propargylation product(3a,b) in the moderate yield. The relative stereochemistry of 3a,b are obtained on the basis of ¹H-NMR analysis. And the possible reaction mechanism are suggested by the molecular models in the transition state.

      • N-Arylnortropinone 유도체의 합성연구

        李龍均,朴유미,鄭大一,金寅植,朴鍾勳,盧信愛,鄭逸守,朴敏洙 東亞大學校附設基礎科學硏究所 1998 基礎科學硏究論文集 Vol.15 No.1

        Tropinone 화합물들은 색다른 고리계의 존재로 아주 오래전부터 약리학적으로 매우 흥미로운 연구과제로 주목되어 최근에 그들의 합성법,?? 입체적 구조분석?? 그리고 약리학적인 연구??가 활발히 진행되고 있다. Tropinone 1은 흔히 마약으로 알려져 있는 cocaine 2, 소염작용과 항경련성 작용 및 심장박동수를 조절 등 다양한 약리작용을 하는 tropane spirohy-dantoin ?? 그리고 안과질환을 검사 할 때 눈의 동공을 확장시키는 데 사용하는 atropine ??등을 합성하는 데 중요한 중간체이다. ??????????? Trigo, G, G등 ??은 aliphatic amine과 succinic aldehyde를 acetonedicarboxylic acid와 반응하여 nortropane 유도체를 합성하였으며, 그 후 [3+2] nitrone cycloaddition? 과 [3+4] cyclocoupling? 을 거치는 tropane alkaloid의 새로운 합성법이 개발되었다. 최근 lzquier M. L. 등¹은 acetonedicarboxylic acid를 사용하여 1차 지방족 amine과 succinic aldehyde대신 2,5-dimethoxytetrahydrofuran을 반응시켜 N-alkyl nortropinone 유도체를 합성하였다. 그러나 일반적으로 빙초산 속에서 amine과 2,5-dimethoxytetrahydrofuran을 반응시키면 pyrrole 유도체가 합성되어진다.?? 이러한 사실은 분명히 반응조건(예, 산, 온도)에 따른 다양한 화학이 존재한다고 볼 수 있다. 따라서 우리는 반응조건, 즉 산의 변화 및 온도 변화에 의한 amine과 2,5-dimethoxytetrahydrofuran의 반응을 자세하게 검토하면서 새로운 N-arylnortropinone 유도체를 합성하고자 한다.

      • AFB₁ 대사에서 phloretion의 이중 활성 효과

        임대원,이광,고상상,진효연,은상용,최병민,김복량 圓光大學校 醫科學硏究所 2008 圓光醫科學 Vol.23 No.1

        Aflatoxm B₁(AFB₁) is a potent hepatocarcinogen in experimental animals and a hazard to human health in several parts of the world. AFB₁ is activated to its ultimate carcinogenic intermediate, AFB₁-8,9-epoxide, by cytochrome P450(CYP) 1A2 and CYP3A4 in human liver and the intermediate is decomposed by several glutathione S-transferase(GST) including GSTA2, GSTM1 and GSTP1. In this study, we investigated the effects of phloretin on the enzyme systems which are involved in the activation and detoxification of AFB₁. The metabolic intermediate of AFB₁ was measured with HPLC. We found that phloretin could strongly inhibit the activities of CYP 3A4 and CYP1A2 in a dose dependent manner. Phloretin induced the antioxidant-response element(ARE)-mediated gene expression, including GSTs. The expressions of GSTA2, T1, M1, and GSTP1 were induced by 10μM phloretin. The decomposition of AFB₁-8,9-epoxide was measured with GSH conjugating activity of the epoxide. The rate was increased to 1.5 fold when HepG2 cells were treated by 10μM phloretin for 12h. In the mean while, the total GST activitives toward CDNB in HepG2 cells were not changed by the treatment with phloretin. The results demonstrate that phloretin has strong chemopreventive effects against AFB₁ toxicity through the inhibition of AFB₁ activation and induction of GSTs.

      • 달걀껍질(생, 삶은)의 수처리에 관한 연구

        정대일,정선주,김인식,최영하,류정숙,이용균,최순규 동아대학교 환경문제연구소 1999 硏究報告 Vol.22 No.2

        The selective absorption ability of low density heavy metal(Pb(Ⅱ) ion or Cu(Ⅱ) ion) of eggshell(raw or boiled) is better than one of existing absorption materials in treatment ability and experimental condition. The elimination ability of chlorine of eggshell(raw or soiled) is worse than one of active carbon. In elimination of trihalomethane, the effect of treatment of eggshell is almost the same as one of pine cones. And surface of eggshell(raw or boiled) after absorption of heavy metal ion was observed by Scanning Electron Microscope(SEM). Application and availability of eggshell(raw or boiled) as absorption material need lots of experiments. The experiment on baked eggshell is proceeding.

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