• 제목/요약/키워드: Heterocyclic

검색결과 315건 처리시간 0.021초

Manipulation of Absorption Maxima by Controlling Oxidation Potentials in Bis(tridentate) Ru(II) N-Heterocyclic Carbene Complexes

  • Kim, Hyeong-Mook;Jeong, Daero;Noh, Hee Chang;Kang, Youn K.;Chung, Young Keun
    • Bulletin of the Korean Chemical Society
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    • 제35권2호
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    • pp.448-456
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    • 2014
  • A series of seven Ru(II) complexes bearing NHC ligands have been synthesized. The electronic structures of these complexes were analysed by spectroscopic and electrochemical methods and further examined by theoretical calculations. Data show that absorption maxima are dependent on the HOMO level rather than the HOMO-LUMO gaps.

Heterocyclic Synthesis with Nitriles: New Routes for Synthesis of Pyridazines, Pyridines and their Fused Derivtives

  • Negm, Abdalla-M.;Abdelrazek, Fathy-M.;Elnagdi, Mohamed-H.;Shaaban, Lina-H.
    • Archives of Pharmacal Research
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    • 제17권6호
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    • pp.411-414
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    • 1994
  • Phenylazocyanothioacetamide 1 reacts with malononitrile to afford the pyridinethione 4 which reacts with phenacylbromide to yield the pyridine-S-phenacyl derivative 6, 1 reacts with ethyl cyanoacetate to yield the pyridazine derivative, 8, and with phenacyl bromide to afford the N-phenacyl derivative 11, instead of the thiazole 10. Compound 11 afforded the pyrazolopyridine 13 on reaction with malononitrile while 10 was obtained on coupling of the thiazole 14 with diazotised aniline. Compound 10 reacts with malononitrile to afford the thizaolyl pyridazine 15. Compound 1 reacts with malononitrile dimer to afford the pyriodopyridazine derivative 17a. 1 reacts also with active methylene heterocycies to afford the pyrazolo and thiazolo-fused phridazines 20 and 23 respectively.

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Sulfonylurea 유도체들의 구조분석 : Acetohexamide와 Tolazamide (Conformational Analysis of Sulfonylureas : Acetohexamide and Tolazamide)

  • 정우태;강기롱;이성희
    • 약학회지
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    • 제39권3호
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    • pp.329-336
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    • 1995
  • Conformational free energy calculations using an empirical potential function and a hydration shell model(program CONBIO) were carried out on hypoglycemic agent acetohexamide and tolazamide in the unhydrated and hydrated states. The initial geometry of sulfonylureas was obtained from X-ray crystallographieal data and homologous molecular fragments. In both states, the feasible conformations were obtained from the calculations of conformational energy, conformational entropy, and hydration free energy by varying all the torsion angles of the molecules. From the calculation results, it is known that the conformations] entropy is the major contribution to stabflize the low-free-energy conformations of two sulfonylureas in both states. But, in hydrated state, the hydration does not directly affect each conformations. The intramolecular hydrogen bonding of sulfonylurea hydrogen and 7-membered nitrogen appeared to the conformations of tolazamide in both states. It is thought that the hydrogen bonding decrease steric hindrance on the receptor binding direction. The substitution of alicyclic or N-heterocyclic ring than that of carbons chain of urea moiety may be properly interaction between sulfonylureas and the putative pancreatic receptor.

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할로겐을 소유한 이원소 고리 화합물에 관한 연구(제 3보) 유기산 또는 Lewis산 존재하에서 이루어진 초산 Furfuryl의 염소화반응 (Halogen Containing Heterocyclic Compounds (Part III) Chlorination of Furfuryl Acetate in Presence of Acid and Lewis Acids)

  • 김유선;이수선;오명원
    • 대한화학회지
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    • 제14권3호
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    • pp.201-206
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    • 1970
  • Furfuryl acetate was chlorinated in presence of acetic acid using carbontetrachloride as the solvent. When the chlorination proceeded at the low concentration of acetic acid, the formation of the tetrachloride was more efficient than that of higher concentration. The chlorination done in presence of various Lewis acids such as aluminum chloride, hydrogen fluoride, and borontrifluoride could not give high yield of tetrachloride, but trichloride. In case of borontrifluoride and hydrogen fluoride, the decomposition of the reaction mixture was apparent. The results were discussed in terms of the stability of furfuryl nucleus towards an electron acceptor and the convenient procedure of preparing trichloro furfuryl acetate was described.

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含할로겐 異元素環化合物에 關한 硏究 (第1報) Furfurylacetate 의 Chlorination 반응 (Halogen Containing Heterocyclic Compounds (Part 1) Chlorination of Furfurylacetate)

  • 김유선;정진성
    • 대한화학회지
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    • 제9권2호
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    • pp.81-87
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    • 1965
  • 醋酸풀퍼릴을 合成하여 여러가지 反應條件下에서 鹽素化시킨 結果 低溫反應에서 安定한 trans 四鹽化物(平均收率 25∼30%)을 生成하였고, 三鹽化物의 生成은 거의 없었다. 高溫反應에서는 反應生成物의 分解가 甚하였다. 鹽素化反應條件, 生成物의 分離方式 및 安定度, 立體化學構造에 對하여 各各 論及하였다.

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An Efficient Synthesis of 3,4-Dihydro-3-substituted-2H-naphtho[2,1-e][1,3]oxazine Derivatives Catalyzed by Zirconyl(IV) Chloride and Evaluation of its Biological Activities

  • Kategaonkar, Amol H.;Sonar, Swapnil S.;Pokalwar, Rajkumar U.;Kategaonkar, Atul H.;Shingate, Bapurao B.;Shingare, Murlidhar S.
    • Bulletin of the Korean Chemical Society
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    • 제31권6호
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    • pp.1657-1660
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    • 2010
  • An efficient and novel one-pot synthesis of new 3,4-dihydro-3-substituted-2H-naphtho[2,1-e][1,3]oxazine derivatives from 1-naphthol, various anilines and formalin at room temperature grinding is presented. The six-membered N,O-heterocyclic skeleton was constructed via zirconyl(IV) chloride promoted Mannich type reaction. In vitro antimicrobial activities of synthesized compounds have been investigated against Gram-positive Bacillus subtilis, Gram negative Escherichia coli and two fungi Candida albicans and Aspergillus niger in comparison with standard drugs. The results of preliminary bioassay indicate that some of title compounds possess significant antibacterial and antifungal activity.

Protein Tyrosine Phosphatase 1B Inhibitors: Heterocyclic Carboxylic Acids

  • Cho, Sung-Yun;Ahn, Jin-Hee;Ha, Jae-Du;Kang, Seung-Kyu;Baek, Ji-Yoen;Han, Sang-Sub;Shin, Eun-Young;Kim, Sung-Soo;Kim, Kwang-Rok;Cheon, Hyae-Gyeong;Choi, Joong-Kwon
    • Bulletin of the Korean Chemical Society
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    • 제24권10호
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    • pp.1455-1464
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    • 2003
  • Several series of compounds (benzoic acids, pyrazolecarboxylic acids, phenoxyacetic acids, and quinolinoxyacetic acids) were prepared and evaluated for their inhibitory activity against PTP-1B. Several compounds showed submicromolar inhibitory activity.

A Facile One-pot Synthesis of Fused 2-Thiouracils: Dipyrimidinopyridine, Pyrazolopyrimidine and Pyridazinopyrimidines

  • Youssif, Shaker;EI-Bahaie, Said;Nabih, Esam
    • Bulletin of the Korean Chemical Society
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    • 제24권10호
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    • pp.1429-1432
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    • 2003
  • A novel fused thiouracil containing a heterocyclic ring system, dipyrimidinopyridine (3), has been prepared through the cyclization of compound 2. Compound 2 was formed by the formylation of 6-amino-2-thiouracil 1, pyrazolopyrimidines 8-10 via the heating of 6-arylhydrazono-2-thiouracils 5-7, compound 11, using Vilsmeier reagent with compound 4, pyrazolylpyrimidine 12, indolodiazinopyrimidine 14 and pyridazinopyrimidine 15. Pyridazino-pyrimidine 15 was formed by the condensation of compound 4 with acetylacetone, isatin and benzyl, respectively.

The Syntheses of 3-Substituted 4-(Pyridin-2-ylthio)indoles via Leimgruber-Batcho Indole Synthesis

  • Srisook, Ekaruth;Chi, Dae-Yoon
    • Bulletin of the Korean Chemical Society
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    • 제25권6호
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    • pp.895-899
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    • 2004
  • We have designed a new family of radioligands, 3-(amino- and hydroxymethyl)-4-(5-iodopyridin-2-ylthio)indoles, combining characteristically distinct moieties proven to impart successful binding ability in a variety of structurally diverse selective serotonin reuptake inhibitors recently published. Described in this article are the syntheses of 3-substituted 4-(5-iodopyridin-2-ylthio)-indoles, featuring successful adaptation of the modified Leimgruber-Batcho indole synthesis onto the key intermediate 1-(5-iodopyridin-2-ylthio)-2-methyl-3-nitrobenzene (6) prepared from the nucleophilic aromatic substitution of chloropyridine 7 with thiophenol 8.

Pyrimidines과 pyrimidine의 헤테로고리의 합성 (Synthesis of Pyrimidines and Heteroannulated Pyrimidine Ring Systems)

  • Mohammed, F.K.;Badrey, M.G.
    • 대한화학회지
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    • 제55권2호
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    • pp.218-229
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    • 2011
  • Imine 화합물 1을 hydrazine hydrate와 같은 nitrogenous 시약과 반응시켜서 치환된 pyrimidines 화합물을 합성하였다. 얻어진 화합물 2를 다양한 반응조건, 즉 propionic acid, formic acid, ethyl chloroformate, acdetic anhydride, carbon disulphide, cyanogene bromide, triflauroacetic acid 및 ethyl chloroacetate와 반응시켜서 대응하는 화합물을 좋은 수율로 얻었으며, 반응은 Dimroth-type 자리옮김 반응을 통하여 진행되었다.