• Title/Summary/Keyword: bromo

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Synthesis of 1-(4'-Thio-${\alpha},{\beta}$-D-ribofuransyl)-5-halogeno Uracils (I) (5-할로겐 치환 uracil 들의 4-Thiosugar Nucleosides의 합성 (제 1 보))

  • Kim Jack C.;Lee Euk-suck;Kim Chang-bae;Bobek Miroslav;Whistlee Roy L.
    • Journal of the Korean Chemical Society
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    • v.19 no.2
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    • pp.130-133
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    • 1975
  • The 4'-thio analogs of the 5-bromo-and 5-iodo-pyrimidine nucleosides were prepared by condensation of 2,3,5-tri-O-acetyl-4-thio-${\alpha},{\beta}$-D-ribofuranosyl chloride with the chloromercury derivatives of 5-halogeno-2,4-bis(trimethylsiloxy)pyrimidine, followed by the removal of the protecting groups. Although the biological activities of the 4'-thio derivatives are not greatly different from the corresponding 4'-oxygen analogs in this preliminary test, the fact that the 4'-thio analogs have comparableihigh activities, is of interest, and indicates the value of further biochemical examinations.

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Studies on the Primary Structure of the Alkaline Protease in Neungee [Sarcodon aspratus (Berk.) S. Ito] I. Amino Acid Composition, Chemical Modification and Sequence of the N-terminal Amino Acid (능이[Sarcodon aspratus(Berk.) S. Ito]중 알카리성 단백질가수분해효소의 1차구조에 관한 연구 I. 아미노산 조성, 활성부위 아미노산 및 N-말단 부위의 아미노산 배열)

  • 이태규
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.22 no.6
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    • pp.811-814
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    • 1993
  • Properties of a protease purified from Sarcodon asparatus(Berk.) S. Ito have been investigated. The enzyme displays as a glycosylated serine protease. The sequence for the 21 amino acids of the N-terminal side in the enzyme was determined by automated sequence analysis. The sequence was V-T-T-K-Q-T-N-A-P-W-G-L-G-N-I-S-T-T-N-K-L-.

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Activation of the cGMP/Protein Kinase G Pathway by Nitric Oxide Can Decrease TRPV1 Activity in Cultured Rat Dorsal Root Ganglion Neurons

  • Jin, Yun-Ju;Kim, Jun;Kwak, Ji-Yeon
    • The Korean Journal of Physiology and Pharmacology
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    • v.16 no.3
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    • pp.211-217
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    • 2012
  • Recent studies have demonstrated that nitric oxide (NO) activates transient receptor potential vanilloid subtype 1 (TRPV1) via S-nitrosylation of the channel protein. NO also modulates various cellular functions via activation of the soluble guanylyl cyclase (sGC)/protein kinase G (PKG) pathway and the direct modification of proteins. Thus, in the present study, we investigated whether NO could indirectly modulate the activity of TRPV1 via a cGMP/PKG-dependent pathway in cultured rat dorsal root ganglion (DRG) neurons. NO donors, sodium nitroprusside (SNP) and S-nitro-N-acetylpenicillamine (SNAP), decreased capsaicin-evoked currents ($I_{cap}$). NO scavengers, hemoglobin and 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (CPTIO), prevented the inhibitory effect of SNP on $I_{cap}$. Membrane-permeable cGMP analogs, 8-bromoguanosine 3', 5'-cyclic monophosphate (8bromo-cGMP) and 8-(4chlorophenylthio)-guanosine 3',5'-cyclic monophosphate (8-pCPT-cGMP), and the guanylyl cyclase stimulator YC-1 mimicked the effect of SNP on $I_{cap}$. The PKG inhibitor KT5823 prevented the inhibition of $I_{cap}$ by SNP. These results suggest that NO can downregulate the function of TRPV1 through activation of the cGMP/PKG pathway in peripheral sensory neurons.

Synthesis and Properties of Blue Emitting Polymers Containing Carbazole Groups

  • Kwon, Young-Hwan;Wang, Hui;Kim, Yeon-Bo;Ryu, Jeong-Tak;Chang, Seung-Hyun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.473-474
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    • 2005
  • Blue-emitting polymers containing carbazole units In main chains were synthesized by palladium catalyzed polycondensation of aniline with dibromo-substituted monomers such as 3,6-dibromocarbazole, N-(2-ethylhexyl)-3,6-dibromocarbazole, and bis[6-bromo-N-(2-ethylhexyl)-carbazole-3-yl], respectively. All synthesized polymers exhibited relatively good solubility in common organic solvents, considerable molecular weights and high resistance to thermal degradation. From UV-Vis absorption and photoluminescence (PL) spectra of these solution-processable polymers, $\lambda_{max,UV}$ were in the range of 290 ~ 340 nm and $\lambda_{max,PL}$ were in the blue emission range of 440 ~ 478 nm, The polymers had HOMO energy (-5.19 ~ -5.64 eV) and wide band gap energy (2,91 - 3.42 eV).

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Effects of Radish Seed Ethanol Extracts on Gastrointestinal Function in Rats

  • Lee, Chang-Hyun;Lee, Moon-Won;Song, Geun-Seoup;Kim, Young-Soo
    • Food Science and Biotechnology
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    • v.15 no.4
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    • pp.599-602
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    • 2006
  • The effects of ethanol extract from radish seeds on gastrointestinal function in rats were investigated. Rats were divided into 2 groups of 8 rats each, the basal group and the radish seed ethanol extract group. The radish seed ethanol extract group had a significantly decreased gastrointestinal transit time, but a significantly increased fecal weight compared with the basal group. The radish seed ethanol extract group also had significantly higher duodenal villus height and greater colonic mucosal thickness than the basal group. The radish seed ethanol extract group had a greater proliferation of 5-bromo-2-deoxy-uridine (BrdU) immunoreactive cells in the gastric mucosa as well as in the mucosa and submucosa of the small and large intestine than did the basal group. Thus, radish seed ethanol extract may be useful in preventing constipation based on the observation of an increase in fecal weight, a decrease in gastrointestinal transit time, and positive changes in the intestinal mucosa.

A Gas Phase Kinetic Study on the Thermal Decomposition of $ClCH_2CH_2CH_2Br$

  • Kim, Sung-Hoon;Choo, Kwang-Yul;Jung, Kyung-Hoon
    • Bulletin of the Korean Chemical Society
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    • v.10 no.3
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    • pp.262-269
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    • 1989
  • The gas phase thermal decomposition of 1-bromo-3-chloropropane in the presence of radical inhibitor was studied by using the conventional static system. The mechanism of unimolecular elimination channel is shown below. [...] In this scheme, the total molecular dissociation rate constant, ($k_1\;+\;k_2$), for the decomposition of $BrCH_2CH_2CH_2Cl$ was determined by pyrolyzing the $BrCH_2CH_2CH_2Cl$ in the temperature range of $380-420^{\circ}C$ and in the pressure range of 10∼100 torr. To obtain $k_3\;and\;k_4,\;and\;to\;obtain\;k_1\;and\;k_2$ independently, the thermal decompositions of allyl chloride and allyl bromide were also studied. The Arrhenius parameters for each step are as follows; $log\;A_{\infty}\;=\;14.20(sec^{-1}),\;E_a$ = 56.10(kcal/mol) for reaction path 1; $log\;A_{\infty}\;=\;12.54(sec^{-1}),\;E_a$ = 49.75(kcal/mol) for reaction path 2; $log\;A_{\infty}\;=\;13.41(sec^{-1}),\;E_a$ = 50.04(kcal/mol) for reaction path 3; $log\;A_{\infty}\;=\;12.43(sec^{-1}),\;E_a$ = 52.78(kcal/mol) for reaction path 4; Finally, the experimentally observed pressure dependence of the rate constants in each step is compared with the theoretically predicted values that are obtained by the RRKM calculations.

Bezoin in Heterocyle Synthesis: Synthesis and Reactions of 2, 3-Diphenyl-4-cyanopyrrole-5-thione

  • Khalifa, Fathy A.;Zohdi, Hussein F.;Ibrahim, M.K.A.;Ismail, N.A.
    • Archives of Pharmacal Research
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    • v.13 no.4
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    • pp.351-354
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    • 1990
  • 2, 3-diphenyl-4-cyano-pyrrole-5-thione (4) was either by the reaction of benzoin (1) and cyanothioacetamide (3) followed by cyclization using AcOH/sodium acetate or by refluxing a mixture of benzoin (1) and cyanothioacethamide in pyridine to afford directly 4. Several new pyrrole and pyrazole derivatives were synthesised using 4 as synthon. The structure of the newly synthesised derivatives were based on celemental and spectral data studies. Methylation of the SH group in 4 afforded 5. Reaction of 4 with ethyl bromo acetate afforded (6). Treatment of (5) and (6) with hydrazine hydrate afforded the same pyrazole derivative (10) through the intermediate (9). Treatment of 6 with aniline and phenylhydrazine afforded the pyrrole derivatives 8a, b respectively. Treatment of 6 while dill HCI gave 2, 3-diphenyl-4-cyano-pyrrole-5-one (7). Treatment of 6 with $NH_3$/EtOH afforded the amidic derivatives (11) with treatment of 6 $NH_3$/ heat then acidification it gave the carboxylic derivatives (12).

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Synthesis and Properties of Diarylamino-Substituted Linear and Dendritic Oligoquinolines for Organic Light-Emitting Diodes

  • Lee, Ho-Joon;Xin, Hao;Park, Seong-Min;Park, Seog-Il;Ahn, Taek;Park, Dong-Kyu;Jenekhe, Samson A.;Kwon, Tae-Woo
    • Bulletin of the Korean Chemical Society
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    • v.33 no.5
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    • pp.1627-1637
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    • 2012
  • The coupling reaction between 5-bromo-3-phenylbenzo[c]isoxazole and diphenylamine followed by further condensation with a mono-, di- or ter-acetyl aromatic compound in the presence of diphenyl phosphate at $145^{\circ}C$ gave a novel asymmetric diarylquinolines, oligoquinolines with diphenylamine endgroups, and a first generation quinoline dendrimer in 41-82% isolated yield. The electrochemical and photophysical properties of the oligoquinolines were characterized by cyclic voltammograms (CVs) and spectroscopy. All the quinolines emit bright sky blue light due to charge transfer from quinoline group to diphenly amine with very high quantum efficiency (> 90%). Organic light-emitting diodes (OLEDs) were fabricated using these quinolines as emitting materials. Among different device architectures explored, OLEDs with a structure of ITO/PEDOT (40 nm)/TAPC (15 nm)/D-A quinoline (40 nm)/TPBI (30 nm)/LiF (1 nm)/Al using TAPC as an electron blocking layer and TPBI as a hole blocking layer gave the best performance. A high external quantum efficiency in the range of 1.2-2.3% were achieved in all the quinolines with the best performance in BBQA(5). Our results indicate diarylamino-substituted oligoquinoline and dendrimer are promising materials for OLEDs applications.

Synthesis and Properties of New Phthaloperinone Dyes containing Anthraquinone Moiety (Anthraquinone을 포함하는 신규 Phthaloperinone 색소의 합성과 특성에 대한 연구)

  • Jun, Kun;Gwon, Seon Yeong;Kim, Yu Jin;Kim, Sung Hoon
    • Textile Coloration and Finishing
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    • v.28 no.2
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    • pp.57-62
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    • 2016
  • We have synthesized five novel phthaloperinone dyes via a condensation reaction to be applied as yellow colorants for liquid crystal display(LCD) color filters. The reaction between 1,8-naphthalic anhydride(1a), 4-chloro-1,8-naphthalic anhydride(1b), 4-bromo-1,8-naphthalic anhydride(1c), 3-nitro-1,8-naphthalic anhydride(1d), 4-nitro-1,8-naphthalic anhydride(1e) and 1,2-diaminoanthraquinone(2) proceeded readily giving a product in 72-88% yields. The synthesized dyes were characterized by UV-Vis, mass spectrometry and elemental analysis. The spectral properties and thermal stability of the dyes were examined. The dyes absorb at around 400-450nm. All five dyes showed satisfactory thermal stability: the dyes retain 99-100% of its original weight at $300^{\circ}C$, 98-100% at $350^{\circ}C$, 92-98% at $400^{\circ}C$, and 84-92% at $450^{\circ}C$. We have quantitatively evaluated the reaction mechanism and reactivity of dye molecules by means of Pariser-Parr-Pople Molecular Orbital Method(PPP-MO).

Effect of Ecklonia cava Extracts Supplementation on cognitive ability in mice (감태(甘苔)에서 추출한 Dieckol 성분이 쥐의 인지능력에 미치는 영향)

  • Oh, Jae-Keun;Song, Ki-Jae;Ji, Mu-Yeop;Yoon, Jin-Ho
    • The Korea Journal of Herbology
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    • v.29 no.6
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    • pp.103-109
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    • 2014
  • Objectives : The purpose of this study aimed to investigate that dieckol - isolated from Ecklonia cava - supplementation can improve cognitive ability in mice. Methods : 48-male mice(6 weeks old) were divided into four groups; High-Dieckol group(n=12), Low-Dieckol group(n=12), Placebo group(n=12), Control group(n=12) and they were administered orally 5 days per week for 4 weeks at the same time. We performed Morris water maze test, Passive avoidance test, Blood serotonin analysis. And there was examined on neurogenesis in dentate gyrus of hippocampus using 5-bromo-2'-deoxyuridine (BrdU) to label proliferating cells. Results : The results are as follows; As a Morris water maze results, Trial duration was significantly decreased in high dieckol group comparing to placebo group and control group. Distance to target was significantly decreased in high dieckol group and low dieckol group comparing to placebo group and control group. Mean speed was significantly low in high dieckol group comparing to low dieckol group, placebo group and control group. As a Passive avoidance test results, latency time was significantly long in high dieckol group comparing to low dieckol group, placebo group and control group. BrdU cell count was significantly high in high dieckol group comparing to low dieckol group, placebo group and control group. Conclusions : As a conclusion, it is considered that dieckol supplementation might improve learning and cognitive ability.