• 제목/요약/키워드: N_4

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4-(2'-(N-(1-메틸-3-(3'-카바밀페닐)-n-프로필))아미노에틸)-1-히드록시-2- 피리돈의 합성 (Synthesis of 4-(2'-(N-(1-methyl-3'-carbamylphenyl)-n-propyl))aminoethyl)-1-hydroxy-2-pyridone)

  • 윤성화
    • 약학회지
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    • 제37권1호
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    • pp.36-40
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    • 1993
  • The 4-(2'-(N-(l-methyl-3'-carbamylphenyl)-n-propyl))aminoethyl)-l- hydroxy-2-pyridone which has isoelectronic and isosteric structural similarity with dobutamine without having the Catechol-O- Methyltransferase(COMT) vulnerable m-hydroxy group was synthesized via 12 synthetic steps.

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4-{4'-(니트로페닐아조)펜옥시}알칸 산들 그리고 4-{4'-(니트로페닐아조)펜옥시}알카노일 클로라이드들의 열방성 액정 거동 (Thermotropic Liquid Crystalline Behaviors of 4-{4'-(nitrophenylazo)phenoxy}alkanoic Acids and 4-{4'-(nitrophenylazo)phenoxy}alkanoyl Chlorides)

  • 정승용;마영대
    • 공업화학
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    • 제19권5호
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    • pp.504-511
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    • 2008
  • 두 종류의 니트로아조벤젠 유도체들, 즉 4-{4'-(니트로페닐아조)펜옥시}알칸 산(NAAn, n = 2~8, 10, 알킬 사슬 중의 메틸렌 기의 수) 그리고 4-{4'-(니트로페닐아조)펜옥시}알카노일 클로라이드(NACn, n = 2~8, 10)을 합성함과 동시에 이들의 열방성 액정의 거동을 검토하였다. NAA6은 쌍방성 네마틱 상을 형성하는 반면 NAA2을 제외한 나머지 유도체들은 단방성 네마틱 상을 형성하였다. NAAn 그리고 NACn이 나타내는 액체 상에서 네마틱 상으로의 전이온도($T_{iN}$) 그리고 $T_{iN}$에서의 엔트로피 변화(${\Delta}S$)는 n의 변화에 따라 현저한 홀수-짝수 효과를 나타냈다. 그러나 NAAn의 $T_{iN}$ 그리고 ${\Delta}S$는 n이 동일한 NACn의 $T_{iN}$ 그리고 ${\Delta}S$ 값에 비해 대단히 높았다. 이러한 사실은 카복실 그룹간에 작용하는 수소결합력에 의해 초래되는 것으로 생각된다. NAAn 그리고 NACn이 나타내는 액정 상의 열적 안정성과 질서도 그리고 홀수-짝수 효과는 4-(알콕시)-4'-니트로아조벤젠들에 대해 보고되어 있는 결과와는 현저히 달랐다. 이러한 특성을 분자의 이방성 그리고 온도에 의존하는 치환기 그룹의 유연성 차이 견지에서 검토하였다.

Bulky Side Group을 갖는 폴리벤즈이미다졸의 합성 (Synthesis of Polybenzimidazole Containing Bulky Side Group)

  • 안병현;김원호
    • 폴리머
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    • 제25권6호
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    • pp.796-802
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    • 2001
  • 나프탈렌을 측쇄로 갖는 새로운 폴리벤즈이미다졸 단량체을 합성하고, 이 단량체를 친핵치환반응에 의해 중합하였다. 4-Methoxy-N-naphthyl-1,2-phenylenediamine과 4-fluoro-benzoyl chloride의 반응으로 N-(4-fluorobenzoyl)-4-methoxy-N'-naphthyl-1,2-phenyl-enediamine이 합성되었고 이로부터 고리화반응 및 demethylation에 의해 단량체인 2-(4-fluoro-benzoyl)-5-hydroxy-1-naphthylbenzimidazole이 얻어졌다. 중합반응은 potassium carbonate를 함유하는 N-cyclohexyl-2-pyrrolidinone (CHP)에서 행해졌다. 생성된 폴리벤즈이미다졸은 N-methyl-2-pyrrolidinone (NMP)에 용해되었고 0.38 dL/g (NMP at $30^{\circ}C$)의 대수 점도를 가졌다. 유리전이온도($T_g$)는 $270^{\circ}C$였고 열중량분석에서 5% 중량감소를 보이는 온도는 질소분위기에서는 $550^{\circ}C$, 공기중에서는 $540^{\circ}C$였다.

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Synthesis and Structures of $(NH_4)_{10}[Ni(H_2O)_5]_4[V_2P_2BO_{12}]_6{\cdot}nH_2O$ and $(NH_4)_{3.5}(C_3H_{12}N_2)_{3.5}[Ni(H_2O)_6]_{1.25}{[Ni(H_2O)_5]_2[V_2P_2BO_{12}]_6{\cdot}nH_2O$

  • Yun, Ho-Seop;Do, Jung-Hwan
    • 한국결정학회지
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    • 제15권1호
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    • pp.35-39
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    • 2004
  • Two new nickel vanadium borophosphate cluster compounds, $(NH_4)_{10}[Ni(H_2O)_5]_4[V_2P_2BO_{12}]_6{\cdot}nH_2O$ (1) and $(NH_4)_{3.5}(C_3H_{12}N_2)_{3.5}[Ni(H_2O)_6]_{1.25}{[Ni(H_2O)_5]_2[V_2P_2BO_{12}]_6{\cdot}nH_2O$ (2) have been synthesized and structurally characterized. Inter-diffusion methods were employed to prepare the compounds. The cluster anion $[(NH_4)\;{\supset}\;V_2P_2BO_{12}]_6$ is used as a building unit in the synthesis of new compounds containing $Ni(H_2O){^{2+}_5}$ in the presence of pyrazine and 1,3-diaminopropane. Compounds contain isolated cluster anions with general composition ${[Ni(H_2O)_5]_n[(NH_4)\;{\supset}\;V_2P_2BO_{12}]_6}^{-(17-2n)}$ (n = 2, 4). Crystal data: $(NH_4)_{10}[Ni(H_2O)_5]_4[V_2P_2BO_{12}]_6{\cdot}nH_2O$, monoclinic, space group C2/m (no. 12), a = 27.538(2) ${\AA}$, b = 20.366(2) ${\AA}$, c = 11.9614(9) ${\AA}$, ${\beta}$ = 112.131(1)$^{\circ}$, Z = 8; $(NH_4)_{3.5}(C_3H_{12}N_2)_b[Ni(H_2O)_6]_{3.5}{[Ni(H_2O)_5]_2[V_2P_2BO_{12}]_6{\cdot}nH_2O$, triclinic, space group P-1 (no. 2), a = 17.7668(9) ${\AA}$, b = 17.881(1) ${\AA}$, c = 20.668(1) ${\AA}$, ${\alpha}$ = 86.729(1)$^{\circ}$, ${\beta}$ \ 65.77(1)$^{\circ}$, ${\gamma}$ = 80.388(1)$^{\circ}$, Z = 2.

SiC 부피분율이 $Si_{3}N_{4}/SiC$ 초미립복합재료의 기계적 특성과 미세구조에 미치는 영향 (Effect of SiC volume fraction on mechanical properties and microstructure of $Si_{3}N_{4}/SiC$ nanocomposites)

  • 황광택;김창삼;오근호
    • 한국결정성장학회지
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    • 제6권3호
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    • pp.386-391
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    • 1996
  • $Si_{3}N_{4}$에 평균입경이 270 nm인 SiC 분말을 0, 10, 20, 30, 40 vol% 첨가하여 고온 가압소결법으로 $Si_{3}N_{4}/SiC$ 초미립복합재료를 제조하였다. 소결후 기지상인 ${\alpha}-Si_{3}N_{4}$${\beta}-Si_{3}N_{4}$로 상전이하였으며, 이차상인 ${\beta}-SiC$는 변화가 없었다. 소결조제의 첨가에 의한 입계결정상은 검출되지 않았다. SiC의 첨가량이 많아짐에 따라 $Si_{3}N_{4}$ 결정립성장은 억제되어 미세한 결정입이 나타났으며, 작은 임자는 기지상 임내에 큰 SiC는 임계에 존재하였다. SiC 첨가에 따라 파괴강도는 약간 증가후 감소하였으며, 파괴인성은 감소하였고, 경도는 직선적으로 증가하였다.

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ON THE STABILITY OF A GENERALIZED CUBIC FUNCTIONAL EQUATION

  • Koh, Hee-Jeong;Kang, Dong-Seung
    • 대한수학회보
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    • 제45권4호
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    • pp.739-748
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    • 2008
  • In this paper, we obtain the general solution of a generalized cubic functional equation, the Hyers-Ulam-Rassias stability, and the stability by using the alternative fixed point for a generalized cubic functional equation $$4f(\sum_{j=1}^{n-1}\;x_j\;+\;mx_n)\;+\;4f(\sum_{j=1}^{n-1}\;x_j+mx_n\;x_j\;-\;mx_n}\;+\;m^2\sum_{j=1}^{n-1}\;(f(2x_j)\;=\;8f(\sum_{j=1}^{n-1}\;x_j)\;+\;4m^2{\sum_{j=1}^{n-1}}\;\(f(x_j+x_n)\;+\;f(x_j-x_n)\)$$ for a positive integer $m\;{\geq}\;1$.

TiN 표면위에 텅스텐의 화학증착 (Chemical Vapor Deposition of Tungsten on TiN Surface)

  • 이청;이시우;이건홍
    • 전자공학회논문지A
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    • 제29A권4호
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    • pp.49-57
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    • 1992
  • Tungsten film was deposited on the TiN surface in a low pressure chemical vapor deposition reactor and chemical reaction mechanism between TiN surface and ($WF_{6}\;and\;SiH_{4}$ was studied. Interaction of ($WF_{6}\;or\;SiH_{4}$ with TiN surface and tungsten was deposited more easily. $WF_6$ reacted with TiN activated the TiN surface to form volatile TiF_4$ and tungsten nuclei were formed. ($SiH_{4}$ was dissociated on the TiN surface to form silicon nuclei. From RBS and AES analysis, we could not detect the impurities(such as Si or TiF$_x$)at the interface between tungsten and TiN. The adhesion at the W/TiN interface became poor when the deposition temperature was below 275$^{\circ}C$.

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Photochemical Cleavage of Dibenzoylmethane and Curcumin in the Presence of N,N-Dimethylaniline in Methanol

  • Kim, Sung-Sik;Mah, Yoon-Jung;Kim, Ae-Rhan;Cho, Kyung-Won
    • Journal of Photoscience
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    • 제11권3호
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    • pp.129-132
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    • 2004
  • Photochemically stable dibenzoylmethane and curcumin were cleaved dramatically when they were irradiated in the presence of N,N-dimethylaniline in methanol with 300 nm UV light. Several products such as benzil, secondary product derived from 1,4-diphenyl-1,4-butanedione, and unidentified compound were observed from the photoreactions of dibenzoylmethane with N,N-dimethylaniline. It was also found that one of the primary fragments produced by irradiation of curcumin in methanol were coupled with N,N-dimethylaniline to give a new enone compound, i.e., 1-(4-dimethylaminophenyl)-4-(4-hydroxy-3-methoxyphenyl)-but-3-en-2-one, as the major product.

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Design, Synthesis and Biological Activity of Certain 3,4-Disubstituted-5-mercapto-1,2,4-triazoles and Their Hydrazino Derivatives

  • Udupi, R.H.;Sudheendra, Sudheendra;Bheemachari, Bheemachari;Srinivasulu, N.;Varnekar, Rajesh;Purushottamachar, Puranik
    • Bulletin of the Korean Chemical Society
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    • 제28권12호
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    • pp.2235-2240
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    • 2007
  • 3-Aryloxy methyl-4-(N-pyrazin-2'yl carboxamido)-5-mercapto-1,2,4-triazoles (3a1-a14) were prepared starting from potassium dithio carbazinates (2a1-a14). These triazoles were then employed in the synthesis of 3-aryloxy methyl-4-(N-pyrazin-2'yl carboxamido)-5-hydrazino-1,2,4-triazoles (4a1-a14). All the newly synthesized compounds were characterized by analytical, IR, NMR spectral studies. The compounds were screened for their antibacterial, antifungal, anti-inflammatory and analgesic properties. Most of the compounds have shown significant antifungal activity while few have shown excellent anti-inflammatory and analgesic activity. An attempt is made to study the structure activity relationship (SAR).