• 제목/요약/키워드: 2-Aryl-2

검색결과 402건 처리시간 0.022초

N'-aryl-N-alkyl-N-nitrosourea 유도체의 환원반응에 대한 전기화학적 거동 (Electrochemical Behaviors for Cathodic Reaction of N'-aryl-N-alkyl-N-nitrosourea Drivatives)

  • 원미숙;김정균;정의덕;심윤보
    • 대한화학회지
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    • 제39권11호
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    • pp.842-847
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    • 1995
  • 유리질 탄소전극을 사용하여 조사한 몇가지 N'-aryl-N-alkyl-N-nitrosourea 유도체들의 전기화학적 환원반응은 확산지배적이고 비가역적인 반응이었다. 이들 유도체들의 환원 반응시의 교환속도 상수 $k_0$값은 $1.48{\times}10^{-6}{\sim}5.32{\times}10^{-7}\;cm/sec.$의 값을 나타내었었다. Aryl기 및 alkyl기의 치환기에 따른 교환속도상수는 $k_0$ N'-aryl-N-alkyl-N-nitrosourea 에서 aryl기가 phenyl일 경우, 다른 치환기보다 $k_0$값이 1.3-2.8배였다. N'-aryl-N-alkyl-N-nitrosourea 와 N'-aryl-N-(2-chloroethyl)-N-nitrosourea의 두 화합물에서 aryl기의 치환기가 같을 경우는 비슷한 값을 나타내었다. N'-aryl-N-methyl-N-nitrosourea 유도체는 pH값이 높아짐에 따라 $E_p$값이 음전위쪽으로 이동하며 각 환원 반응에 참여한 $H^+$의 수는 4-5개였다. 이경우 aryl기의 치환기 효과는 환원전위에 크게 영향을 미치지 않는 것으로 나타났다.

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Palladium Catalyzed Carbonylative Vinylation of Aryl Halides with Olefins and Carbon Monoxide

  • Kim, Jin-Il;Ryu, Cheol-Mo
    • Bulletin of the Korean Chemical Society
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    • 제8권4호
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    • pp.246-250
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    • 1987
  • The reaction of aryl iodides or bromides with olefins in the presence of 1 mol % of $PdCl_2(PPh_3)_2$ and 3 equiv. of $n-Bu_3N\; at\; 100^{\circ}C$ in carbon monoxide atmosphere gave the corresponding aryl vinyl ketones in good yields with small amount of vinylated 1-aryl olefins. But, when the reaction was proceeded under the 10 atm of carbon monoxide, aryl vinyl ${\alpha}$-diketones and aryl vinyl ketones were obtained in moderate to good yields. The reaction was tolerant of a wide variety of functional groups on either the aryl halides or olefin compounds. Reactivity of aryl halide decrease in the order; aryl iodide > aryl bromide ${\gg}$aryl chloride. In general, the reaction proceeded well and gave good yields of aryl vinyl ketones and aryl vinyl ${\alpha}$-diketones when reactants are substituted with electron withdrawing groups.

Palladium-Catalyzed Cross-Coupling Reaction and Gold-Catalyzed Cyclization for Preparation of Ethyl 2-Aryl 2,3-Alkadienoates and α-Aryl γ-Butenolides

  • Mo, Jun-Tae;Hwang, Hoon;Lee, Phil-Ho
    • Bulletin of the Korean Chemical Society
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    • 제32권spc8호
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    • pp.2911-2915
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    • 2011
  • Efficient synthetic method for the preparation of ethyl 2-aryl-2,3-alkadienoates through Pd-catalyzed selective allenyl cross-coupling reactions of aryl iodides with organoindiums generated in situ from indium and ethyl 4-bromo-2-alkynoate was developed. The cyclization reaction of ethyl 2-aryl-2,3-alkadienoates catalyzed by $AuCl_3$ and AgOTf in the presence of AcOH or TfOH produced various ${\alpha}$-aryl ${\gamma}$-butenolides or ${\gamma}$-substituted ${\alpha}$-aryl ${\gamma}$-butenolides.

Synthesis of 1-Aryl-2-mercapto-4-aryl-1,6-dihydro-1,3,5-triaszine-6-thione and their Latentiation Products as Antithyroidal Agent

  • Methrotra, S.;Roychowdhury, P.K.;Pandey, K.K.;Srivastava, P.K.
    • Archives of Pharmacal Research
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    • 제18권5호
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    • pp.356-360
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    • 1995
  • Two new 1-aryl-2-benzylmercapto-4-aryl-1,6-dihydro-1,3,5-triazine-6-thiones hvae been synthesized by known methods (Coerdeler et al., 1967). These triazines on treatment with thiourea as dealkylating agent, in acidic medium afforded the corresponding 1-ary-2-mercapto-4-aryl-1,6-dihydro-1,3,5-triazine-6-thione which on further reaction with different ${\alpha},{\;}{\beta}-unstaturated$ carbonyl compounds and aryl-cyanamide ydrochloride affordered the related adducts. Some of these compounds show appreciable antithyroidal activity.

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7-데아자퓨린 유도체의 합성 (Synthesis of 7-Deazapurine Derivatives)

  • 신관석;남재우;이창규;전종갑
    • 약학회지
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    • 제37권3호
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    • pp.228-234
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    • 1993
  • A new series of 7-deazapurine derivatives[7,8] as purine antagonists was prepared. Diethyl 4-cyano-N-(diphenyimethylene)-3-arylglutamate[3] were synthesized by LDA-catalyzed Michael addition of N-(diphenylrnethylene)glycine ethyl ester with (E)-2-cyano-3-arylacrylate. Deprotection yields diethyl 4-cyano-3-arylglutamate, which were easily cyclized to 4-cyano-2-ethoxycarbonyl-5-oxo-3-arylpyrrolidine[4]. The compounds[4] were treated with NaBH$_{4}$ and then with (C$_{2}$H$_{5}$)$_{3}$OBF$_{4}$ to give 4-cyano-5-ethoxy-2H-2-ethoxymethyl-3-aryl-3,4-dihydropyrrole[6], which were converted to 7-aryl-6-amino-8-ethoxymethyl-7,8-dihydro-7(3H, 9H)-deazapurine-2-thione[7] and 7-aryl-2,6-diamino-8-ethoxymethyl-7,8-dihydro-7(9H)-deazapurine[8] with possible activity against neoplastic disease.

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Synthesis of New Oxazolin-5-ones Derivatives as Antibacterial Agents

  • Moharram, H.H.;El-Amin, S.A.
    • Archives of Pharmacal Research
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    • 제11권3호
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    • pp.175-180
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    • 1988
  • 1-Aryl-4-arylidene-2-oxazoline-5-ones (I) and the corresponding unsaturated amidoesters (II) and arylidene hypuric acid hydrazide (III) were obtained. The hydrazides and 1-aryl-1,3-dithiophenol-2-amidopropan-3-ones derivatives (IV) were also obtained. The derivatives were tested for their antibacterial activities.

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Pd(CF3CO2)2 착화합물 촉매에 의한 방향족 탄소-수소 결합의 활성화 반응 (Activation of Aromatic Carbon-Hydrogen Bonds by Palladium Trifluoroacetate Complexes)

  • 황영애;김동환;백두종
    • 대한화학회지
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    • 제50권5호
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    • pp.369-373
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    • 2006
  • Pd(CF3CO2)2-phosphine 및 Pd(CF3CO2)2-sulfide 계를 촉매로 사용하여 styrene의 아릴화반응을 연구하였다. 주 생성물인 trans-stilbene의 수율은 phosphine 치환체의 염기도가 증가할수록 높아졌고 입체장애가 클수록 낮아졌다. arylphosphine에서 styrene으로 aryl 기가 이동하는 현상은 동일한 arylphosphine에 대하여 Pd(CF3CO2)2의 경우가 더 높은 염기도를 가진 Pd(CH3CO2)2의 경우보다 더 많이 나타났으므로 이 반응은 Pd 이온이 먼저 aryl 기에 공격을 하는 친전자성 메커니즘에 의해 진행된다고 본다. 한편 Pd(CF3CO2)2-sulfide보다 Pd(CF3CO2)2-phosphine 계가 더 효과적인 촉매로 작용하였다.

Effect of the Aryl Substituent on Antitumor Activity of 2-Substituted-1,4-dihydroxy-9,10-anthraquinones and 2-Substituted-anthracene-1,4,9,10-tetraones

  • Nam, Nguyen-Hai;Jin, Guang-Zhu;Tam, Mai-Ngoc;Ahn, Byung-Zun
    • Archives of Pharmacal Research
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    • 제22권6호
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    • pp.592-607
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    • 1999
  • 2-(1-Aryl-1-hydroxymethyl)-and 2-aroyl-DHAQ derivatives (DHAQ, 1,4-dihydroxy-,10-anthraquinone), and 2-(1-aryl-1-hydroxymethyl)-ATO derivatives (ATO, anthraceneactivity (T/C 125~128%), though their cytotoxicity was not further improved compared to that of 2-(1-aryl-1-dydroxymethyl)-1,4-dihydroxy-9,10-anthraquinones. They manifested no correlation between the cytotoxicity and the antitumor activity. In case of 2-[1-hydroxy-1-(4-propylphenyl)-methyl]-ATO, the most bioactive one in viv-1,4,9,10-tetraone) were synthesized and their antitumor activities were determined. 2-(1-Aryl-1-hydroxymethyl)-DHAQ derivatives showed a stronger cytotoxicity compared to the series of 2-(1-hydroxyalkyl)-1,4-dihydroxy-9,10-anthraquinone derivatives. It was suggested that the presence of aryl group at the side chain accelerated the bioreductive activation leading to cell death. 2-Aroyl-DHAQ derivatives, despite their higher electrophilicity, revealed smaller cytotoxicity and antitumor activity (expressed by T/C value) than 2-(1-aryl-1-hydroxymethyl)-DHAQ derivatives. Thus, no consistent relationship between the electronic effect on aromatic side chain and the cytotoxicity was observed. ATO series exhibited a higher antitumor o among the same series, it showed an $ED_{50}$ value of 10.2 mg/mL and a T/C value of 218%. It is assumed that the anthrancene1,4,9,10-tetraones after uptake into cellular tissues might be transformed to a cytotoxic metabolite(s).

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