• 제목/요약/키워드: Convergent synthesis

검색결과 44건 처리시간 0.042초

Synthesis and Characterization of Aliphatic Polyether Dendrons Based on Polystyrene Peripheries

  • Song, Jie;Kim, Hyun-Yu;Cho, Byoung-Ki
    • Bulletin of the Korean Chemical Society
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    • 제28권10호
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    • pp.1771-1776
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    • 2007
  • The synthesis of well-defined dendrons based on aliphatic polyether dendritic cores and glassy polystyrene peripheries is described. The synthetic route involves a combination of living anionic polymerization and a stepwise convergent method consisting of iterative Williamson etherification and hydroboration/oxidation reactions. On the basis of molecular weight, as characterized by gel permeation chromatography (GPC), the first generation dendron (Generation-1) shows a random coil conformation like a linear polystyrene, while higher generations (Generation-2 and 3) reveal globular forms in solution.

A new synthesis route to nucleoside: Two-directional synthesis of carbocyclic nucleoside using double [3,3] -sigmatropic rearrangement and double RCM

  • Kim, Ji-Hee;Zhe Fang;Kim, Kwan-Woo;Hong, Joon-Hee
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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    • pp.243.1-243.1
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    • 2003
  • Extensive efforts in the search of therapeutically useful carbocyclic nucleosides have resulted in a wealth of their synthetic methodologies in racemic and optically active forms. The classical one-directional methods such as linear synthesis and convergent synthesis are the approaches most frequently seen in the literature for the preparation of carbocyclic nucleosides, and their advantages and limitations are well known. (omitted)

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열분해 연료유 및 PET 기반 활성탄을 이용한 NO 가스 센서의 감도 향상 연구 (NO Gas Sensor with Enhanced Sensitivity Using Activated Carbon Prepared from Pyrolysis Fuel Oil and Polyethylene Terephthalate)

  • 곽철환;서상완;김민일;임지선;강석창
    • 공업화학
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    • 제32권1호
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    • pp.42-48
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    • 2021
  • 본 연구에서는 열분해 연료유를 이용하여 석유계 피치 기반 활성탄을 제조하였고, 이를 활용하여 일산화질소 가스 검출 센서를 개발하였다. 피치의 분자량 증가를 위해 피치 합성 시 중합 반응을 촉진시키는 폴리에틸렌 테레프탈레이트를 첨가하였다. 피치의 분자량 증가는 피치 기반 활성탄의 비표면적 및 미세기공 부피 증가에 기여하였고, 이는 활성탄 기반 센서의 일산화질소 가스 검출 특성 향상시켰다. 또한 테레프탈레이트 첨가 피치를 사용할 때 활성탄의 표면 산소 관능기 및 전도성 변화를 확인하고 테레프탈레이트 첨가가 활성탄의 물성 및 일산화질소 가스 검출 특성에 미치는 영향을 분석하였다.

Efficient Synthesis of Bibenzyl Derivatives Bearing Pyranyl Moieties: First Total Synthesis of Bauhinol D

  • Park, Byung-Ho;Lee, Yong-Rok;Kim, Sung-Hong
    • Bulletin of the Korean Chemical Society
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    • 제32권2호
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    • pp.566-570
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    • 2011
  • An efficient and general synthesis of bibenzyl derivatives bearing pyranyl rings was achieved by ethylenediamine diacetate-catalyzed reactions of 3,5-dihydroxybibenzyl with ${\alpha},{\beta}$-unsaturated aldehydes in moderate yields. These reactions provided naturally occurring compounds 1 and 2 in single step reaction. As an application of this methodology, biologically interesting natural bauhinol D (8) was synthesized by a convergent sequence from readily available benzaldehyde and benzyl phosphonate.

First Total Synthesis of Prorepensin with a Bis-Geranylated Chalcone

  • Jung, Eun-Mi;Lee, Yong-Rok
    • Bulletin of the Korean Chemical Society
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    • 제30권11호
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    • pp.2563-2566
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    • 2009
  • The first total synthesis of naturally occurring prorepensin with a bis-geranylated chalcone has been achieved by a convergent sequence. The key strategy involved in the synthesis of prorepensin was chalcone formation by aldol condensation of the corresponding geranylated acetophenone with geranylated benzaldehyde.

A Convergent Synthesis of Bis-2-oxo Amide Triacylglycerol Analogues as Potent Lipase Inhibitors Using Acyl Cyanophosphorane Methodology

  • Lee, Kie-Seung
    • Bulletin of the Korean Chemical Society
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    • 제23권2호
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    • pp.351-354
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    • 2002
  • A number of bis-2-oxo amide triacylglycerol analogues, a recently reported potent human gastric lipase inhibitor and its new analogues, have been prepared starting from 1,3-dibromo-2-propanol utilizing acyl cyanophosphorane methodology as a key step in a convergent manner. The key coupling reaction has been accomplished at -$78^{\circ}C$ between 1,3-diamino-2-propanol derivative and the labile diketo nitriles, derived from acyl cyanotriphenylphosphoranes upon oxidizing with $O_3$, under mild condition in moderate yields.

Convergent Synthesis and Characterization of Dumbbell Type Dendritic Materials by Click Chemistry

  • Sung, Sae-Reum;Han, Seung-Choul;Jin, Sung-Ho;Lee, Jae-Wook
    • Bulletin of the Korean Chemical Society
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    • 제32권11호
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    • pp.3933-3940
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    • 2011
  • General, fast, and efficient stitching methods for the synthesis of dendrimers with linear PEG units at a core, as dendritic-linear-dendritic materials, were developed. The synthetic strategy involved the click reaction between an alkyne and an azide. The linear core building blocks, three dialkyne-PEG units, were chosen to serve as the alkyne functionalities for dendrimer growth via click reactions with the azide-dendrons. These three building blocks were employed together with the azide-functionalized Fr$\acute{e}$chet-type dendrons in a convergent strategy to synthesize the Fr$\acute{e}$chet-type dendrimers with different linear core units. Their structure of dendrimers was confirmed by $^1H$ and $^{13}C$ NMR spectroscopy, IR spectroscopy, mass spectrometry, and GPC analysis.