• Title/Summary/Keyword: Regioselective synthesis

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Regioselective Benzylic Thioether Formation from Polybydroxy Stilbene

  • Koh, Dongsoo;Park, Jongmin;Lim, Yoongho
    • Journal of Applied Biological Chemistry
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    • v.44 no.1
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    • pp.20-22
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    • 2001
  • We have attempted to synthesize polyhydroxy stilbene compounds through the benzyl thioether moiety. During synthesis, we unexpectedly observed that demethylation of the compound under $AlCl_3$ in ethanethiol resulted in a regioselective addition of thiol to the double bond as well as complete demethylation. We report on the regioselective short synthesis for general structure and its structural identification.

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Regioselective Synthesis of Ginsenoside $Rh_2$ (진세노사이드 $Rh_2$의 방향선택적 합성)

  • 신명희;정지형;장은하;임광식
    • YAKHAK HOEJI
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    • v.45 no.4
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    • pp.328-333
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    • 2001
  • Ginsenoside Rh$_2$, a minor glycoside constituent of the red ginseng is known as an unique antitumor compound. Several attempts to prepare it in a large scale including semisynthesis from betulafolientriol, an 3-epimer of 20(S)-protopanaxadiol, has been reported. We have previously reported a synthesis of ginsenoside Rh$_2$from 20(S)-protopanaxadiol obtained by alkaline hydrolysis of total ginsenoside. The regioselective synthesis of this compound was achieved by protection of 12-OH group.

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Regioselective Enzymatic Acylation of Multi-hydroxyl Compounds in Organic Synthesis

  • Park, Hyun-Gyu;Do, Jin-Hwan;Chang, Ho-Nam
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.8 no.1
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    • pp.1-8
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    • 2003
  • With current developments in enzyme-catalyzed reactions and techniques available for rational redesign of natural biocatalysts, the enzymatic biosynthesis can become one of the most valuable Synthetic methods. Enzymatic regioselective catalysis in organic media has played a key role in pursuing asymmetric synthesis for active chiral compounds. Here, we shortly do-scribe some historical issues of the rapidly growing area, enzymatic catalysis in synthetic organic chemistry and then review researches that have been carried out in the regioselective enzymatic catalysis for the past two decades. An application of this technology to the modification of some potential target drug co m pound will be adios presented.

A Green One-Pot Protocol for Regioselective Synthesis of New Substituted 7,8-Dihydrocinnoline-5(6H)-ones

  • Khalafy, Jabbar;Rimaz, Mehdi;Ezzati, Mahnaz;Prager, Rolf H.
    • Bulletin of the Korean Chemical Society
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    • v.33 no.9
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    • pp.2890-2896
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    • 2012
  • A simple regioselective synthesis of cinnoline derivatives was achieved by a one-pot three component synthetic methodology. New substituted 7,8-dihydrocinnolin-5(6H)-ones are prepared via one-pot three component reaction of arylglyoxals with 1,3-cyclohexanedione and dimedone in the presence of hydrazine hydrate in moderate to good yields.

Improved One-pot Regioselective Synthesis of 3,7-Diarylpyrazolo[1,5-α]pyrimidines and Their CB1R Activity (3,7-Diarylpyrazolo[1,5-α]pyrimidines의 개선된 One-pot Regioselective 합성과 CB1R 활성)

  • Hong, Yong Deog;Byoun, Kyoung Hee;Park, Miyoung;Park, Jun Seong;Shin, Song Seok
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.41 no.2
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    • pp.143-150
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    • 2015
  • This study demonstrates an effective one-pot regioselective synthesis of 3,7-diarylpyrazolo [1,5-${\alpha}$]pyrimidines. Moreover, the derivatives obtained were effective CB1R antagonists. These pyrazolo [1,5-${\alpha}$]pyrimidines with diaryl groups at the 3,7-positions are potential pharmacophores for CB1R candidates.

Synthesis and Vibrational Spectroscopic Study of Selectively $3^1-^{18}O$-Labelled Chlorophyll Derivatives

  • Morishita, Hidetada;Tamiaki, Hitoshi
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.356-358
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    • 2002
  • Regioselective 3$^1$-$^{18}$ O-labelling of chlorophyll derivatives possessing a 3-formyl group such as methyl (pyro) pheophorbide-d (3, 4) was carried out efficiently by a simple one-step procedure; by stirring a homogeneous solution of tetrahydrofuran and H$_2$$^{18}$ O containing a small amount of trifuluoroacetic acid.

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