• 제목/요약/키워드: Macrocyclic

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Structure and Properties of a Nonheme Pentacoordinate Iron(II) Complex with a Macrocyclic Triazapyridinophane Ligand

  • You, Minyoung;Seo, Mi Sook;Kim, Kwan Mook;Nam, Wonwoo;Kim, Jinheung
    • Bulletin of the Korean Chemical Society
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    • 제27권8호
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    • pp.1140-1144
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    • 2006

  • A macrocyclic ligand, N,N',N'-tribenzyl-2,11,20-triaza[3,3,3](2,6)pyridinophane (BAPP), was used to prepare an iron(II) complex as a nonheme model complex, $[(BAPP)Fe]^{+2}$ (1). X-ray crystallography of a colorless crystal of 1 revealed that BAPP acted as a pentadentate ligand due to geometrical strain for the formation of a six-coordinate iron(II) complex by BAPP. As a result, the iron center revealed a significantly distorted square pyramidal geometry similar to that found in the active site of taurine dioxygenase (tauD). In the reaction of 1 with PhIO, no intermediate was observed in the UV-visible region of spectrometer at low temperatures. Catalytic oxidations of triphenyl phosphine with PhIO at ${-40^{\circ}C}$ revealed that 1 was able to convert triphenyl phosphine to triphenyl phosphine oxide.23; SSOCHKThioanisole was also oxidized to the corresponding methylphenyl sulfoxide under the same conditions.

  • https://doi.org/10.5012/bkcs.2006.27.8.1140 인용 PDF KSCI

Characterization of Antibiotic Substance Produced by Serratia plymuthica A21-4 and the Biological Control Activity against Pepper Phytophthora Blight

  • Shen, Shun-Shan;Piao, Feng-Zhi;Lee, Byong-Won;Park, Chang-Seuk
    • The Plant Pathology Journal
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    • 제23권3호
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    • pp.180-186
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    • 2007

  • The biocontrol agent, Serratia plymuthica A21-4, has been developed for controlling pepper Phytophthora blight. Serratia plymuthica A21-4 strongly inhibits the mycelial growth, zoospore formation, and cyst germination of Phytophthora capsici in vitro. The application of a cell suspension of strain A21-4 to pepper plants in pot experiments and in greenhouse successfully controlled the disease. The bacteria produced a potent antifungal substance which was a key factor in the suppression of Phytophthora capsici. The most active chemical com-pound was isolated and purified by antifungal activity-guided fractionation. The chemical structure was identified as a chlorinated macrolide $(C_{23}H_{31}O_8Cl)$ by spectroscopic (UV, IR, MS, and NMR) data, and was named macrocyclic lactone A21-4. The active compound significantly inhibited the formation of zoosporangia and zoospore and germination of cyst of P. capsici at concentrations lower than $0.0625{\mu}g/ml$. The effective concentrations of the macrocyclic lactone A21-4 for $ED_{50}$ of mycelial growth inhibition were $0.25{\mu}g/ml,\;0.25{\mu}g/ml,\;0.30{\mu}g/ml \;and\;0.75{\mu}g/ml$ against P. capsici, Pythium ultimum, Sclerotinia sclerotiorum and Botrytis cinerea, respectively.

  • https://doi.org/10.5423/PPJ.2007.23.3.180 인용 PDF KSCI

3-Acyl-4(S)-isopropyl-1,3-Thiazolidine-2-Thione과 라세미아민의 입체선택적인 반응 (A Highly Stereoselective Reaction in Aminolysis of 3-Acyl-4-(S)-isopropyl-1,3-thiazolidine-2-thione with Racemic Amines)

  • 정태명;박기훈
    • 대한화학회지
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    • 제32권6호
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    • pp.588-592
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    • 1988

  • 키랄 보조제가 붙어있는 3-acyl-4(S)-isopropyl-1,3-thiazolidine-2-thione[4(S)-AITT]을 라세미 아민과 가아민 분해반응을 시켰을때 광학활성을 갖는 아미드(S-excess)와 아민(R-excess)이 얻어지는 입체 선택적인 반응이 관찰되었다. 이와같은 입체 선택적인 반응은 macrocyclic diamide, macrocylic sperimidine alkaloid, peptide 합성에 이용될 수 있다. 가아민 분해반응의 속도는 아민의 입체적인 영향을 많이 받았고 반응이 종료점은 노락색의 소실로 쉽게 관찰되었다. 4(S)-AITT는 4(S)-isopropyl-1,3-thiazolidine-2-thione과 carboxylic acid로부터 얻었다.

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