• 제목/요약/키워드: Reaction products

검색결과 2,632건 처리시간 0.029초

Total synthesis of Antofine by using Intramolecular 1.3-dipolar cycloaddition of Azidealkene

  • Lee, Jae-Kwang;Lee, Tae-Ho;Song , So-Young
    • 대한약학회:학술대회논문집
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    • 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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    • pp.362.2-362.2
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    • 2002
  • Antofine belongs to the Phenathroindolizidine group of alkaloids. This natural products exhibit interesting biological properties such as antitumour activity. and anti-inflammentory. Wittig reaction of phenathrenealdehyde with the phosponium salt provided the phenathreneazidealkene in good yield. Intramolecular 1.3-dipolar cycloaddition of the resulting azidealkent in refluxing benzene proceeded the imine. It was reduced with cyanoborohydride of Noyori's Asymmetric Hydrogenation. (omitted)

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Vanadium Haloperoxidase의 구조와 작용 메커니즘과 해양천연물질 (Reaction Mechanism of Vanadium Haloperoxidase and Marine Natural Products)

  • 한재홍
    • 한국결정학회지
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    • 제16권2호
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    • pp.66-74
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    • 2005
  • 다양한 생리활성을 가지는 marine natural products는 일반적인 secondary metabolites와 유사한 구조를 가지는데, 염소, 브롬, 요오드의 할로겐 원소에 의해 수식이 되어있는 것이 일반적이다. Vanadium haloperoxidase는 이러한 marine natural products의 생산에 중요한 효소로 vanadate를 조효소로 하는 금속효소이다. 본 리뷰에서는 vanadium haloperoxidase의 분리와 단백질 구조를 살펴보고, 이 금속효소의 작용기작에 대해서 설명할 것이다. 마지막으로, vanadium haloperoxidase의 반응성과 secondary metabolites 중 indole, terpenoids, acetogenins의 생합성 예를 살펴볼 것이다.

기상반응(CVD)법 의한 실리카 미분말의 제조 (Preparation of Ultrafine Silica Powders by Chemical Vapor Deposition Process)

  • 최은영;이윤복;신동우;김광호
    • 한국재료학회지
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    • 제12권11호
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    • pp.850-855
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    • 2002
  • Silica powders were prepared from $SiCl_4$-$H_2$O system by chemical vapor deposition process, and investigated on size control of the products with reaction conditions. The products were amorphous and nearly spherical particles with 130nm~50nm in size. The size distribution became narrow with the increase of [$H_2$O]/[SiCl$_4$] concentration ratio. The particle size decreased with the increase of reaction temperature, [$H_2$O]/[SiCl$_4$] concentration ratio and total flow rate. The specific surface area measured by BET method was about three times larger than that of electron microscope method.

황화 $Ni-W/\gamma-Al_2O_3$ 촉매에 의한 Dibeenzothiophene의 수첨탈황반응 (Hydrodesulfurization of Dibenzothiophene by Sulfided $Ni-W/\gamma-Al_2O_3$ Catalyst)

  • 김경림;정지원
    • 한국대기환경학회지
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    • 제2권2호
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    • pp.51-59
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    • 1986
  • Hydrodesulfurization of dibenzothiophene (DBT) dissolved in n-heptane was studied over sulfided $Ni - W/\gamma - Al_2O_3$ catalyst at temperature ranges from 513 to 573 K and at pressure ranges from 20 to 60 x $10^5$ Pa. Hydrogenation of biphenyl (BP) and cyclohexylbenzene (CHB) observed in products were also run. The products were almost biphenyl and cyclohyxylbenzene, and the conversion of DBT was very sensitive to temperature. Concerning the products distribution while the formation of biphenyl decreased, the formation of cyclohexylbenzene increased in the range of high pressure. The reaction network was found to be sequential reaction which formed cyclohexybenzent through the intermediate of biphenyl. The disappearances of DBT and biphenyl were the first order with respect to DBT and biphenyl and their activation energys were 24.3 and 13.6 Kcal/mol, respectively.

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열처리에 따른 고려홍삼의 수용성 갈변물질의 특성 (Characteristics of the Water Soluble Browning Reaction of Korean Red Ginseng as Affected by Heating Treatment)

  • 이종원;이성계
    • Journal of Ginseng Research
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    • 제22권3호
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    • pp.193-199
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    • 1998
  • The purpose of this study was to Investigate characteristics of the water soluble browning reaction products (WS-BRPs) from Korean red ginseng by heat treatment. Absorbance of WS- BRPs was increased with increases of heating temperature and time, but pH value were decreased In Muter color value L and b value were decreased, while a value was increased. and absorbance at 280 nm in spectrum of the WS-BRPs was increased according to the increase of heating temperature. When the WS-BRPs were applied on Bio-Gel P-30 column after heating and pH treatment, two majors browning products increased according to the progress on time. And pH 3.0 increased in quantity of high molecular fractions and pH 8.0 increased in quantity of low molecular fractions.

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시베리아산 전나무 바이오매스의 아세톤 용매분해반응 (Acetone Solvolysis of a Siberian Spruce Biomass)

  • 윤성욱
    • 한국수소및신에너지학회논문집
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    • 제20권1호
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    • pp.55-63
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    • 2009
  • In this study, thermochemical degradation by acetone solvolysis reaction of siberian spruce wood was investigated for a temperature range of $200{\sim}400^{\circ}C$. The liquid products by acetone solvolysis from siberian spruce wood produced various kinds of aliphatics, cyclic compounds and aromatics included phenols etc. Combustion heating value of liquid products by acetone solvolysis conversion processes was in the range of $8,010{\sim}8,180cal/g$. The energy yield in acetone solvolysis of siberian spruce wood was as high as 74.2% after 40min of reaction at $400^{\circ}C$. The liquid products from the thermochemical conversion of siberian spruce wood could be used as high-octane-value fuels and fuel additives.

마이크론 이하 단위의 제품생산 최적화를 위한 화학공정의 스케일업 (Scale-up of Optimized Chemical Processes for Micron and Submicron Products)

  • 정영미
    • 공업화학
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    • 제28권1호
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    • pp.17-22
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    • 2017
  • 본 총설에서는 마이크론 사이즈 이하 제품에 대한 최적화적인 화학공정의 스케일업을 위한 전략을 소개한다. 최적화된 화학공정의 스케일업을 위해 구해야 할 스케일업 인자의 정의와 이를 도출하는 방법을 소개하였으며, 특히 무반응 시스템, 유반응 시스템으로 분류하여 각각에 대해 서로 다른 스케일업 인자를 찾은 기준을 소개하고, 예시를 들어 논의하였다. 본지에서 소개된 스케일업 인자를 구하는 방법론이 마이크론 사이즈 이하 제품에 대한 화학공정을 스케일업하고자 하는 엔지니어들에게 초기 지침서가 될 것으로 기대된다.

키틴과 파추출액 반응물의 항암 작용 (Antitumor Activity of Reaction Mixture of Chitin and Green Onion Extract)

  • 김영식;박경신;장일무;현진원;박재갑;박호군
    • 약학회지
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    • 제38권5호
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    • pp.579-585
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    • 1994
  • Antitumor activity was tested by administration of reaction mixture of green onion extract and chitin to mice bearing sarcoma-180 cells. An intraperitoneal injection of mixture(20 mg/kg/day) to mice Have an 52% inhibition of tumor growth. Inhibition of tumor growth was found to be dose-dependent. When eighty miligrams of the mixture were administered, the weight of tumor was reduced significantly. HPLC analysis indicated the mixture was composed of N-acetyl-D-glucosamine, N-acetylchitobiose and N-acetylchitotriose.

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Synthesis and Biological Investigations of New Thiazolidinone and Oxadiazoline Coumarin Derivatives

  • Abd Elhafez, Omaima Mohamed;El Khrisy, Ezz El Din Ahmed Mohamed;Badria, Farid;Fathy, Alaa El Din Mohamed
    • Archives of Pharmacal Research
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    • 제26권9호
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    • pp.686-696
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    • 2003
  • Ethyl (coumarin-4-oxy)acetate 1 was prepared through the reaction of 4-hydroxycoumarin with ethyl bromoacetate. Compound 1 was allowed to react with hydrazine hydrate to produce coumarin-4-oxyacetic hydrazide 2. The synthesis of N-(arylidene and alkylidene)-coumarin-4-oxyacetic hydrazones 3-20 was performed. The preparation of 2-substituted-3-[(coumarin-4-oxy) acetamido]thiazolidinones 21-26 and 2-[(coumarin-4-oxy )methyl]-4-acetyl-5-substituted-$\Delta^2$-1,3,4-oxadiazolines 27-33 was performed by the reaction of the hydrazones 3, 4, 7, 9, 12, 14 with mercaptoacetic acid and the hydrazones 3, 4, 5, 7, 12, 15, 16 with acetic anhydride, respectively. The antiviral activities, cytotoxicities and structure-activity relationship (SAR) towards different microorganisms of the prepared compounds were studied.

有機할로겐化合物과 金屬과의 反應 (第 3 報) 有機클로로酸 및 에스터와 各種金屬과의 反應生成物 및 反應系中의 金屬分布에 關하여 (Reaction of Organic Halogen Compounds with metals (Part III) Metal Distribution in the Reaction Products and System of a Reaction between Organo Chloro Acid or Ester and Metals under Various Solvents)

  • 김유선
    • 대한화학회지
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    • 제9권1호
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    • pp.61-65
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    • 1965
  • 有機클로로酸, 또는 에스타와 各種金屬(亞鉛, 硅素, 마그네슘, 錫)과의 여러 溶媒存在下(아세트나이트라일, 디옥센 및 토루엔)의 反應에서 얻은 反應生成物, 또는 反應系中의 金屬分布狀態를 (n,${\gamma}$)反應으로 製造한 各種放射性 金屬트레이서를 使用하여 決定하였다. 有機클로로 金屬 콤푸렉스의 溶解度는 親水性溶媒에서는 顯著하게 增加하였으며, 無極性溶媒에는 減少하였다. 이 事實은 回收된 金屬, 또는 回收된 金屬混合物의 水洗液中의 金屬分布狀態의 增加로서 確認되었다. 카보닐化合物 存在下에서 反應시켰 때에도 같은 事實을 나타내었다. 親水性溶媒中의 金屬콤푸렉스의 溶解度는 亞鉛, 硅素, 錫 및 마그네슘이 順序로 減少되었으며 無極性溶媒下에서는 硅素, 錫, 마그네슘 및 亞鉛의 順으로 減少되었다. 有機할로겐化合物과 金屬과의 反應生成物로 普通 豫期되는 有機金屬化合物은 全反應을 通하여 거의 없었다. 反應結果를 論議하였으며, 本反應過程에서 觀察한 溶媒의 影響에 關하여 論及하였다.

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