• 제목/요약/키워드: C$_{}$ 6/-compounds

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새로운 H-자형 이메소겐 화합물의 액정특성에 치환기가 미치는 효과 (The Effect of Substituents on the Liquid Crystalline Behavior of New H-Shaped Dimesogenic Conpounds)

  • 박주훈;진정일
    • 대한화학회지
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    • 제42권3호
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    • pp.315-322
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    • 1998
  • 새로운 에메소겐 액정화합물들을 합성하였고, 이들의 열적 및 액정 성질을 DSC와 가열판이 부착된 편광현미경을 사용하여 조사하였다. 이 화합물들 즉, 1,10-bis[2,5-bis(4-substitutedphenoxycarbonyl)phenoxy]decane은 "H-자형" 이합체 대칭화합물의 구조로 중앙의 테페프탈로일 단위에 oxydecamethyleneoxy 격자를 통하여 상호 연결된 두 개의 bis(p-substitutedphenoxy)terephthalate 단위로 이루어졌다. 메소겐의 치환기는 X=-F, -H, -I, -Cl, -Br, $-NO_2,\;-CF_3,\;-OC_4H_9-CN$$-C_6H_5$를 바꾸어 보았다. $X=-OC_4H_9-CN$$C_6H_5$ 화합물은 단방성 네마틱액정이었으며 이에 비하여 X=-F, -H, -I, -Cl, -Br, $-NO_2$$-CH_3$는 액정이 아니었다. 이 화합물들의 네마틱 그룹 효율은 $-C_6H_5>-CN>-OC_4H_9$ 순이었다.

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알릴티오피리다진 유도체 합성 및 UV-C조사에 대한 방어효과 (Synthesis of Allylthiopyridazine Derivatives and their Protective Effects of W-C Irradiation)

  • 권순경;현진원
    • 약학회지
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    • 제44권1호
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    • pp.9-15
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    • 2000
  • Four 3-alkoxy-6-allylthiopyridazines and 3-chloro-6-allylthiopyridazine were synthesized and their protective effects against oxidative stress and UV-C irradiation were tested. 3-Methoxy-6-allylthiopyridazine and 3-ethoxy-6-allylthiopyridazine did not show protective effect on the oxidative stress but showed the strongest protective effect on UV-C irradiation among the tested compounds. Especially 500 $\mu\textrm{g}$/$m\ell$ of the two compounds was the most effective concentration.

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Synthesis of certain N-Aryl-N'-(2-pyrimidinyl)guanidine derivatives as potential antimicrobial agents

  • Eisa, H.M.;Tayel, M.A.;Yousif, M.Y.;El-Kerdway, M.M.
    • Archives of Pharmacal Research
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    • 제13권1호
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    • pp.78-81
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    • 1990
  • N-Aryl-N'(4-hydroxy-6-methyl-2-pyrimidinyl)guanidines (IIa-c) were prepared by cyclization of N-arybiguanides (Ia-c) with ethyl acetoacetate. Coupling of compounds (IIa-c) with the appropriate diazotized arylamine gave N-aryl-N'-(5-arylhydrazono-6-methyl-4-oxopyrimidin-2-yl) guanidines (IIIa-f). Whereas, their chlorination with phosphorus oxychloride followed by treatment of N-aryl-N'-(4-Chloro-6-methyl-2-pyrimidinyl)guanidimes (IVac) with the appropriate arylamine afforded the corresponding 4-arylamino derivatives (Vaf). Compounds (IIa-f) were also formed when compounds (1a-c) were treated with ethyl 2-arylhydrazono-3-oxobutyrates. The antimircobial testing of some of the prepared compounds against some pathogenic microorganisms revealed that only two have a marked effect against Escherichia coli.

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시무나무(Hemiptelea davidii) 심재의 성분과 그 항산화 활성 (The Chemical Structures and Their Antioxidant Activity of the Components Isolated from the Heartwood of Hemiptelea davidii)

  • 장복심;권용수;김창민
    • 생약학회지
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    • 제35권1호통권136호
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    • pp.80-87
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    • 2004
  • From the $CHCl_3$ and BuOH soluble fractions of the heartwood of Hemiptelea davidii, eleven compounds have been isolated. On the basis of spectral data, they were identified as ${\beta}-sitosterol$ (1), scopoletin (2), kaempferol (3), 4-hydroxybenzoic acid (4), 2-(4-hydroxyphenyl) ethanol (5), aromadendrin (6), scopolin (7), kaempferol 6-C-glucoside (8), aromadendrin 6-C-glucoside (9), taxifolin 6-C-glucoside (10) and quercetin 6-C-glucoside (11), respectively. Among these compounds, compounds 3, 8, 10, and 11 showed potent DPPH radical scavenging activity with $IC_{50}$ values of 11.9, 14.7, 10.3 and $6.2\;{\mu}g/ml$, respectively.

${\alpha},{\omega}$-비스[4-(4'-(S)-(+)-2-메틸부틸비페닐-4-카르복시)페녹시]알칸 -새로운 디메소겐 화합물의 합성 및 액정성 (${\alpha},{\omega}$-Bis[4-(4'(S)-(+)-2-methylbutylbiphenyl-4-carboxy)phenoxy]alkanes-Synthesis and Liquid Crystalline Properties of New Dimesogenic Compounds)

  • 김재훈;이수민;진정일
    • 대한화학회지
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    • 제42권6호
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    • pp.679-695
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    • 1998
  • A series of ${\alpha}{\omega}-bis[4-(4'-(S)-(+)-2-methylbutylbiphenyl-4-carboxy)phenoxy]alkanes$, were synthesized, and their thermal and liquid crystalline properties were studied. The chain length of the central polymethylene spacers, x, of the chiral twin compounds was varied from 3 to 12. These compounds were characterized by elemental analysis, IR and NMR spectroscopy, differential thermal analysis (DSC), and crosspolarized microscopy. All compounds were found to be enantiotropic liquid crystalline, and the values of melting $(T_m)$ and isotropization temperature $(T_i)$ as well as ${\delta}H_I$ and ${\delta}S_I$ decreased in a zig-zag fashion, revealing the so called odd-even effect as x increased. Their mesomorphic properties fell into four categories depending upon x; (a) compounds with x=3, 4 and 5 formed only a cholesteric phase on heating, while on cooling they went through two transitions of isotropic (I)-to-cholesteric (Ch) and Ch-to-smectic $A\;(S_A)$ phases before crystallization. (b) compounds with x=6, 8 and 10 exhibited only a cholesteric phase both on heating and on cooling. (c) compounds with x=7 and 9 went through three transitions of crystal $(C)-to-S_A,\;S_A-to-Ch,$ and Ch-to-I phases on heating while on cooling they went through four transitions of I-to-Ch, $Ch-to-S_A,\;S_A-to-Smectic\;C\;(S_C),\;and\;S_c-to-C$ phases in that order, and (d) compounds with x=11 and 12 went reversibly through four transitions of $C-to-S_C,\;S_C-to-S_A,\;S_A-to-Ch,$ and Ch-to-I phases.

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Phenolic Compounds from Frullania nisquallensis

  • Kim, Youn-Chul;Kingston, David G.I.
    • 생약학회지
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    • 제26권3호
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    • pp.248-252
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    • 1995
  • Five phenolic compounds were isolated from the MeCOEt extract of Frullania nisquallensis (Jubulaceae), namely methyl 2,4-dihydroxy-3,6-dimethylbenzoate, methyl 2,4-dihydroxy-6-methylbenzoate, acacetin, betuletol, and pectolinaringenin. Revised ${13}^C-NMR$ data of methyl 2,4-dihydroxy-6-methylbenzoate and betuletol are reported.

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참치 가공부산물로부터 단백질 분해효소를 이용한 기능성 천연조미료 제재의 개발 2. 분말 참치 가수분해물의 향미성분 (Development of Functional Seasoning Agents from Skipjack Processing By-product with Commercial Proteases 2. Flavor Compounds in Powdered Skipjack Hydrolysate)

  • 김은정;차용준
    • 한국식품영양과학회지
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    • 제25권4호
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    • pp.617-626
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    • 1996
  • 참치 가공 부산물로부터 제조한 가수부내물의 질소 화합물의 경우 생시료에서는 3.91g%인 반면에, 가수분해물에서는 24.94g%로서 생시료에 비해 6.4배 이상의 높은 함량을 나타내었다. 생시료에서는 lysine이 889.13mg%로서 전체 아미노산 함량의 22.73%를 차지하였고, 그 외 taurine, 3-methylhistidine, anserine, alanine의 순으로 함량이 많았으나 가수분해물에서는 anserine이 3,041.12mg%로서 전체 함량의 12.19%를 차지하였고 그 외 histidine, leucine, hydroxyproline, arginine, phenylalanine, taurine의 순으로 높은 함량을 나타내었다. 지방산 분석결과에서는 두 시료 모두 포화지방산의 함량이 각각 55.14%와 49.28%로 높았다. 주요 지방산으로는 $C_{16:0}$, $C_{18:0}$, $C_{18:1/}$, $C_{22:6}$가 주요 지방산으로서 전체 함량의 75% 정도를 차지하였으며 특히 가수분해물 중의 polyene산은 생시료에 비해 1.4배 높게 나타났다. 휘발성 향기성분을 분석한 결과 총 99종의 화합물이 동정되었는데 이중에서 생시료에서는 75종의 화합물이, 가수분해물에서는 72종의 화합물이 검출되었다. 그리고 이들은 주로 알데히드류(28종), 케톤류(20종), 알콜류(19종), 함질소화합물류(5종), 방향족화합물류(10종), 퓨란류(4종)와 기타 화합물류(12종)으로 구성되어 있었다. 특히 산화취성분인 알데히드류 및 방향족화합물은 생시료에 비하여 가수분해물에서는 상당량 감소된 반면, 고소한 향기성분인 heterocyclic 화합물이 상대적으로 증가하였다.다.

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가열조리한 오만둥이된장찌개의 휘발성 향기성분 (Volatile Flavor Compounds in Omandungi (Styela plicata)-Doenjang (Soybean paste) Soups and stew by Cooking)

  • 정은정;조우진;차용준
    • 생명과학회지
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    • 제18권11호
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    • pp.1570-1577
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    • 2008
  • 오만둥이된장찌개의 가열조리에 따른 열유도반응물질을 규명하여 오만둥이를 이용한 가공기술의 기초자료를 제공하고자 향기성분을 분석하였다. 총 128종의 휘발성 향기성분은 에스테르류(16종), 방향족화합물류(14종), 함질소화합물류(11종), 알콜류(34종), 테르펜류(5종), 카르보닐화합물류(23종), 퓨란류(4종), 탄화수소류(13종), 산류(5종) 및 기타화합물류(3종)로 구성되어 있었다. 된장의 향기성분은 방향족화합물, 알콜류 및 산류의 순으로 많았고, 가열 반응 후 pentanoic acid (불쾌취)는 감소하였으며 열유도 화합물인 furfural을 주로 한 퓨란류가 약 2배로 증가하였다. 오만둥이의 향기성분은 decenol, 2,6-dimethylheptanol 및 octanol이 주된 성분인 알콜류, 탄화수소류 및 방향족화합물 순으로 많았다. 가열 반응 후에는 pentanol의 함량이 증가하였고, 함질소아미노산과 카르보닐화합물의 열유도화합물인 2-acetyl-2-thiazoline 및 benzothiazole과 같은 함황고리화합물이 생성되었다. 오만둥이 된장국에서는 오만둥이에서 유리되는 decenol 및 2,6-dimethylheptanol을 주로한 알콜류, 방향족화합물, 탄화수소류 및 된장가열 후 생성된 benzeneacetaldehyde가 주된 카르보닐 화합물이 많았다. 즉 오만둥이 된장국은 독특한 오만둥이향을 함유한 동시에 된장의 구수한 향미를 보유함을 알 수 있었다

Phenolic Compounds from Desmodium caudatum

  • Li, Wei;Sun, Ya Nan;Yan, Xi Tao;Yang, Seo Young;Choi, Chun Whan;Kim, Young Ho
    • Natural Product Sciences
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    • 제19권3호
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    • pp.215-220
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    • 2013
  • Three C-glucosyl flavones (1 - 3), one xanthone (4), and four flavanonols (5 - 8) were isolated by various chromatographic methods from the leaves and stems of Desmodium caudatum (Thunb.) DC. Chemical structures of these compounds were elucidated by 1D and 2D NMR and mass spectroscopy. The compounds were identified as swertisin (1), spinosin (2), 7-methyl-apigenin-6-C-${\beta}$-glucopyranosyl-2"-O-${\beta}$-D-xylopyranoside (3), 1,3,5,6-tetrahydroxyxanthone (4), yokovanol (5), aromadendrin (6), 2'-hydroxy yokovanol (7), and 2'-hydroxy neophellamuretin (8). Compounds 2 - 4 were first isolated from D. caudatum, as well as the spectroscopic data for compound 3.

Synthesis and Antifungal Activity of 6,7-Bis-[S-(Aryl)thio]-5,8-Quinolinediones

  • Ryu, Chung-Kyu;Sun, Yang-Jung;Shim, Ju-Yeon;You, Hea-Jung;Choi, Ko-Un;Lee, Hee-Soon
    • Archives of Pharmacal Research
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    • 제25권6호
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    • pp.795-800
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    • 2002
  • 6,7-Bis-[S-(aryl)thio]-5,8-quinolinediones 4 and 5 were synthesized by the substitution of 6,7-dichloro-5,8-quinolinediones with appropriate arylthiols. Their antifungal activity were tested in vitro for their growth inhibitory activities against pathogenic fungi in comparison with flucytosine. The antifungal activities were significantly improved by S-(aryl)thio moieties of the compounds 4 and 5. The all tested compounds 4 and 5 showed generally good activities against C. albicans and A. niger ranging from 0.8 to 25 $\mu\textrm{g}$/ml. Among them, compounds 4d-4h and 5a-5c exhibited also good activities against C. krusei and C. tropicalis. The activities of compounds 4j and 4I were comparable to those of flucytosine against all tested fungi.