• 제목/요약/키워드: Regiochemistry

검색결과 6건 처리시간 0.02초

4차 아민이 치환된 아닐린의 고리화반응 메카니즘 및 Pyrrolo[1,2-a]benzimidazoquinone 유도체의 합성에의 응용 (Mechanistic Studies for the Cyclization of t-Amine Substituted Anilines and Their Utilization to the Synthesis of Pyrrolo[1,2-a]benzimidazoquinone Derivatives)

  • 이창희;백호진;김국진;조규욱;오경택
    • 대한화학회지
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    • 제39권5호
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    • pp.408-413
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    • 1995
  • A few t-amine substituted anilines and amides were synthesized and cyclized to pyrrolo[1,2-a]benzimidazole by heating in various solvents having different polarity. Subsequent nitration of cyclized compound followed by reduction and oxidation of resulting amine afforded quinone such as 7 in 14% yield. The formation of imidazole moiety by thermal cyclization was independent on the solvent polarity. The regiochemistry for the nitration of 4 was unambiguously determined by chemical transformation.

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Oxidative Potential of Some Endophytic Fungi Using 1-Indanone as Substrate

  • Fill, Taicia Pacheco;Silva, Jose Vinicius Da;Oliveira, Kleber Thiago De;Silva, Bianca Ferreira Da;Rodrigues-Fo, Edson
    • Journal of Microbiology and Biotechnology
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    • 제22권6호
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    • pp.832-837
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    • 2012
  • The oxidative potential of the fungus Penicillium brasilianum, a strain isolated as endophytic from a Meliaceae plant (Melia azedarach), was investigated using 1-indanone as substrate to track the production of monooxygenases. The fungus produced the dihydrocoumarin from 1-indanone with the classical Baeyer-Villiger reaction regiochemistry, and (-)-(R)-3-hydroxy-1-indanone with 78% ee. Minor compounds that had resulted from lipase and SAM activities were also detected. The biotransformation procedures were also applied using a collection of Penicillium and Aspergillus fungi obtained from M. azedarach and Murraya paniculata. The results showed that Baeyer-Villiger were mostly active in fungi isolated from M. azedarach. Almost all fungi tested produced 3-hydroxy-1-indanone.

Fibrostatins의 부분 합성 (Partial Synthesis of Fibrostatins)

  • 이관희
    • 대한화학회지
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    • 제47권1호
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    • pp.47-58
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    • 2003
  • 알킬화제로 작용할 수 있는 naphthoquinones인 fibrostatin이 Streptomyces catanulae subsp. griseospora 배양액으로부터 추출되었다. 이들 quinone 화합물의 합성은 이 화합물들의 생물학적 반응성 연구에 매우 중요하다. 본 논문에서는 효과적으로 치환체들의 위치를 조절할 수 있는 방법인 Hooker oxidation을 이용하여 fibrostatin B를 합성하였다.

meso-Substituted Dipyrromethanes from Vinylogous Aromatic Heterocycles and Their Utilization to the Synthesis of meso-Functionalized Porphyrins

  • Hong, Seong-Jin;Lee, Mi-Hye;Lee, Chang-Hee
    • Bulletin of the Korean Chemical Society
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    • 제25권10호
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    • pp.1545-1550
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    • 2004
  • meso-Functionalized dipyrromethanes 6-10 were synthesized by acid-catalyzed addition of pyrrole to ${\alpha}$-position of 2-alkenyl pyrroles. The regiochemistry of the reaction can be explained by either the formation of more stable carbocation intermediate or ${\beta}$-addition of ${\alpha},{\beta}$-unsaturated carbonyl compounds. The starting 2-alkenyl pyrroles were synthesized by Aldol condensation of 2-formylpyrrole with active methylene compounds such as nitromethane, diethylmalonate and malononitrile. Attempted ‘2+2' condensation of meso-diethylmalonyldipyrromethane, meso-(p-tolyl)dipyrromethane and p-tolualdehyde afforded three different porphyrins 12, 13 and 14 in reasonable yields. On the other hand, meso-(nitromethyl)dipyrromethane with p-(tbutyl) benzaldehyde resulted in the formation of three different porphyrins such as 5,15-dicyano-10,20-diarylporphyrin (16), 5-cyano-15-formyl-10,20-diarylporphyrin (17) and 5,15-diformyl-10,20-diarylporphyrin (18) in low yields. Conversion of nitromethyl groups to nitrile and (or) formyl group was observed under the porphyrin forming conditions.