• Title/Summary/Keyword: isothiocyanate

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New Synthesis of Perhydrotriazolotriazoles Catalyzed by TiCl4 under Ambient Conditions

  • Safari, J.;Gandomi-Ravandi, S.;Ghotbinejad, M.
    • Journal of the Korean Chemical Society
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    • v.56 no.1
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    • pp.78-81
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    • 2012
  • Aromatic 2,3-diazabuta-1,3-dienes in glacial acetic acid with isothiocyanate in the presence of catalyst $TiCl_4$ at room temperature produced via criss-cross cycloaddition reactions the corresponding perhydro[1,2,4]triazolo[1,2-a][1,2,4] triazole-1,5-dithiones in relatively high yields and short reaction time.

Kinetics and Mechanism of the Pyridinolysis of Diethyl Isothiocyanophosphate in Acetonitrile

  • Adhikary, Keshab Kumar;Lee, Hai-Whang
    • Bulletin of the Korean Chemical Society
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    • v.33 no.3
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    • pp.1042-1046
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    • 2012
  • The kinetics and mechanism of the pyridinolysis ($XC_5H_4N$) of diethyl isothiocyanophosphate are investigated in acetonitrile at $55.0^{\circ}C$. The Hammett and Bronsted plots for substituent X variations in the nucleophiles exhibit the two discrete slopes with a break region between X = 3-Ac and 4-Ac. These are interpreted to indicate a mechanistic change at the break region from a concerted to a stepwise mechanism with rate-limiting expulsion of the isothiocyanate leaving group from a trigonal bipyramidal pentacoordinated intermediate. The relatively large ${\beta}_x$ values with more basic and less basic pyridines imply much greater fraction of frontside nucleophilic attack TSf than that of backside attack TSb.

Nanopatterning of Proteins Using Composite Nanomold and Self-Assembled Polyelectrolyte Multilayers

  • Kim, Sung-Kyu;Kim, Byung-Gee;Lee, Ji-Hye;Lee, Chang-Soo
    • Macromolecular Research
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    • v.17 no.4
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    • pp.232-239
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    • 2009
  • This paper describes the simple nanopatterning of proteins on polyelectrolyte surfaces using microcontact printing with a nanopatternable, hydrophilic composite nanomold. The composite nanomold was easily fabricated by blending two UV-curable materials composed of Norland Optical Adhesives(NOA) 63 and poly(ethylene glycol) dimethacrylate(PEG-DMA). NOA 63 provided stable nanostructure formation and PEG-DMA induced high wettability of proteins in the nanomold. Using the composite mold and functionalized surface with polyelectrolytes, the fluorescent, isothiocyanate-tagged, bovine serum albumin(FITC-BSA) was successfully patterned with 8 nm height and 500 nm width. To confirm the feasibility of the protein assay on a nanoscale, a glycoprotein-lectin assay was successfully demonstrated as a model system. As expected, the lectins correctly recognized the nano-patterned glycoproteins such as chicken ovalbumin. The simple preparation of composite nanomold and functionalized surface with a universal platform can be applied to various biomolecules such as DNA, proteins, carbohydrates, and other biomolecules on a nanoscale.

Development of Two-Component Nanorod Complex for Dual-Fluorescence Imaging and siRNA Delivery

  • Choi, Jin-Ha;Oh, Byung-Keun
    • Journal of Microbiology and Biotechnology
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    • v.24 no.9
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    • pp.1291-1299
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    • 2014
  • Recently, multifunctional nanomaterials have been developed as nanotherapeutic agents for cellular imaging and targeted cancer treatment because of their ease of synthesis and low cytotoxicity. In this study, we developed a multifunctional, two-component nanorod consisting of gold (Au) and nickel (Ni) blocks that enables dual-fluorescence imaging and the targeted delivery of small interfering RNA (siRNA) to improve cancer treatment. Fluorescein isothiocyanate-labeled luteinizing hormone-releasing hormone (LHRH) peptides were attached to the surface of a Ni block via a histidine-tagged LHRH interaction to specifically bind to a breast cancer cell line, MCF-7. The Au block was modified with TAMRA-labeled thiolated siRNA in order to knock down the vascular endothelial growth factor protein to inhibit cancer growth. These two-component nanorods actively targeted and internalized into MCF-7 cells to induce apoptosis through RNA interference. This study demonstrates the feasibility of using two-component nanorods as a potential theranostic in breast cancer treatment, with capabilities in dual imaging and targeted gene delivery.

In Vitro Cellular Uptake and Cytotoxicity of Paclitaxel-Loaded Glycol Chitosan Self-Assembled Nanoparticles

  • Park, Ji-Sun;Cho, Yong-Woo
    • Macromolecular Research
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    • v.15 no.6
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    • pp.513-519
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    • 2007
  • Self-assembled nanoparticles have great potential to act as vehicles for hydrophobic drug delivery. Understanding nanoparticle cellular internalization is essential for designing drugs intended for intracellular delivery. Here, the endocytosis and exocytosis of fluorescein isothiocyanate (FITC)-conjugated glycol chitosan (FGC) self-assembled nanoparticles were investigated by flow cytometry and confocal microscopy. The cellular internalization of FGC nanoparticles was initiated by nonspecific interactions between nanoparticles and cell membranes. Although adsorptive endocytosis of the nanoparticles occurred quickly, significant amounts of FGC nanoparticles were exocytosed, particularly in the early stage of endocytosis. The amount of exocytosed nanoparticles was dependent on the pre-incubation time with nanoparticles, suggesting that exocytosis is dependent on the progress of endocytosis. FGC nanoparticles internalized by adsorptive endocytosis were distributed in the cytoplasm, but not in the nucleus. In vitro cell cycle analysis demonstrated that FGC nanoparticles delivered paclitaxel into the cytoplasm and were effective in arresting cancer cell growth.

Changes in Antimicrobial Activity of Hydrolyzate from Mustard Seed (Brassica juncea) (겨자 가수분해물의 항균성 변화)

  • 서권일;박석규;박정로;김홍출;최진상;심기환
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.25 no.1
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    • pp.129-134
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    • 1996
  • 겨자의 가수분해 시간에 따른 향균력을 비교하고, 각종 미생물에 대한 겨자 물 추출물의 최소 저해 농도 및 최소 저해 투여량을 측정한 결과 다음과 같았다. 겨자의 자가분해 시간에 따른 물 추출물의 향균성은 처음에 아주 약하게 나타났던 것이 12시간 방치 후 크게 증가하였다. 최대 항균활성은 24시간 방치 후 나타났으며 이후 거의 변하지 않았다. 겨자를 첨가한 물의 산도는 시간이 지남에 따라 증가하였고, 겨자의 농도가 클수록 그 정도가 크게 나타났다. $37^{\circ}C에서$ 24시간 자가분해한 겨자 물 추출물의 MID는 Bacillus subtilils가 $70\mu1/disc로$ 다른 실험 균주에 비하여 낮았으며, 젖산균이 $95\mu1/disc로서$ 높게 나타났다. MIC는 Bacillus subtilils, Staphylococcus aureus, Salmonella typhimurium 및 Vibrio parahaemolyticus 균이 $70\mu1/ml로$ 다른 실험 균주에 비하여 낮게 나타났으며, 젖산균 곰팡이에서 $90\mu1/ml로$ 높게 나타났다. 자가분해 시간에 따른 겨자물 추출물의 중류성분은 자가분해 시간이 지남에 다라 점차 증가하는 경향이었고, isothiocyanate 류의 함량은 24시간 때에 최대치를 나타내었다.

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Novel Liquid Crystal Compounds and Its Mixtures for VA-TFT-LCD TV Application

  • Kim, Y.B.;Roh, S.D.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.471-474
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    • 2002
  • Three-ring types liquid crystalline compounds having fluoro and isothiocyanate substituent were synthesized and their physical and electro-optical properties were measured to evaluate the applications to active matrix VA liquid crystal displays. The tetrakis(triphenylphosphine)palladium(0) catalyzed cross coupling of aryl boronic acids with aryl halides is used to prepare trans-4'-Alkoxy-2,3-difluoro-3'-isothiocyanato-4-(4-alkylcyclohexyl}-biphenyl series. The synthesized compounds showed the nematic liquid crystalline phase and the negative dielectric anisotropy. The prepared mixtures showed faster response time and lower threshold voltage than their host mixture.

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Toxicity and Biomedical Imaging of Fluorescence-Conjugated Nanoparticles in Hematopoietic Progenitor Cells

  • Min, Gye-Sik;Kim, Dong-Ku
    • Reproductive and Developmental Biology
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    • v.35 no.4
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    • pp.503-510
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    • 2011
  • Cellular uptake of nanoparticles for stem cell labeling and tracking is a critical technique for biomedical therapeutic applications. However, current techniques suffer from low intracellular labeling efficiency and cytotoxic effects, which has led to great interest in the development of a new labeling strategy. Using silica-coated nanoparticles conjugated with rhodamine B isothiocyanate (RITC) (SR), we tested the cellular uptake efficiency, biocompatibility, proliferation or differentiation ability with murine bone marrow derived hematopoietic stem/progenitor cells. The bone marrow hematopoietic cells showed efficient uptake with SR with dose or time dependent manner and also provided a higher uptake on hematopoietic stem/progenitor cells. Biocompatibility tests revealed that the SR had no deleterious effects on cell cytotoxicity, proliferation, or multi-differentiation capacities in vitro and in vivo. SR nanoparticles are advantageous over traditional labeling techniques as they possess a high level of cellular internalization without limiting the biofunctionality of the cells. Therefore, SR provides a useful alternative for gene or drug delivery into hematopoietic stem/progenitor cells for basic research and clinical applications.

A Study on the Flavor Compounds of Dongchimi (동치미의 맛 성분에 관한 연구)

  • Lee, Mae-Ry;Lee, Hei-Soo
    • Korean journal of food and cookery science
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    • v.6 no.1
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    • pp.1-8
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    • 1990
  • To study the most optimum condition of Dongchimi, the various Dongchimi distinct from the amount of salt, the temperature of fermentation and the ratio of radish to water were examed by sensory evaluation. Also, the content of volatile organic acids and nonvolatile organic acids were investigated by GC, the content of sulfur compounds by GC/MS. Volatile organic acids were identified with those butyl esters and nonvolatile organic acids were done with those TMS derivatives. Sulfur compounds and those decomposed products were extracted by steam distillation In results, the most optimum conditions ware salt 2.4% fermented temperature $4^{\circ}C$, ratio 1:1.5. Volatile organic acids detected were formic, acetic acid, and the amounts were effected by saltness. Nonvolatile organic acids detected were lactio, malio, fumario, tartario acid. Lactic acid was thought to effect overall eating quality. Sulfur compounds were almost the isothiocyanate groups in raw radish, which little in fermented Dongchimi.

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Effect of Sodium Taurodihydrofusidate on Nasal Drug Delivery: Differences in Its Concentration and Penetrant Molecular Weight

  • Hosoya, Ken-ichi;Kubo, Hiroyuki;Takashi-Akutsu;Hideshi-Natsume;Kenji-Sugibayashi;Yasunori-Morimoto
    • Archives of Pharmacal Research
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    • v.17 no.2
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    • pp.57-59
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    • 1994
  • The effect of sodium taurodihydrofusidate (STDHF) on drug permeation across nasal mucosa was studied in vitro using Ussing type diffusion chamber. Disodium cromoglicate (DSCG, M.W.5123) and fluorescein isothiocyanate-dextran (FD) of different molecular wieghts (M.W. 4400-71200) were used as model drugs. Pemeation profiles of DSCG and FDs showed a typical pseudo steady-state curve with short lag time. The pemeability coefficient of FD (M.W. 9400) sigmodially increased with increasing STDHF concentration. It also enhanced the DSCG pemeation. Interestingly the enhancement efficacy was independent of molecular weight of penetrants.

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