• Title/Summary/Keyword: Furan

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Convenient Procedure for the Reduction of Carboxylic Acids via Acyloxyborohydrides

  • Cho, Byung-Tae;Yoon, Nung-Min
    • Bulletin of the Korean Chemical Society
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    • v.3 no.4
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    • pp.149-152
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    • 1982
  • A new convenient method for the reduction of carboxylic acids to the corresponding alcohols via acyloxyborohydrides was explored. Acyloxyborohydrides, prepared from the reaction of various carboxylic acids and sodium borohydride, underwent reduction to the corresponding alcohols readily by the addition of dimethyl sulfate or Lewis acids, such as boron trifluoride etherate and triphenyl borate, presumably through acyloxyboranes. By utilizing this procedure, aliphatic and aromatic acids are rapidly and quantitatively reduced to the corresponding alcohols in terahydrofuran either at room temperature (or at $65^{\circ}$). This procedure provides selective reduction of carboxylic acids in the presence of halogen, nitro, and heterocyclic rings such as furan and thiophene.

A Model Study toward the Synthesis of Xestoquinone and Halenaquinone

  • Ahn, Chan-Mug;Woo, Ho-Bum
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.240.2-240.2
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    • 2003
  • A strategy for synthesis of the furan-fused tetracyclic core of xestoquinone and halenaquinone was explored through a model study. Methyl 8-oxo-4-methyl-4-phenyl-2,7-nonadiynoate was prepared from hydratroponitrile and 3-butyn-1-ol as starting materials. The intramolecular cycloaddition of this intermediate as a key step will be involved.

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Straightforward synthesis of 4'${\alpha}$-C-hydroxymethyl branched novel carbocyclic nucleosides

  • Oh, Jung-Hyo;Kim, Kwan-Woo;Hong, Joon-Hee
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.354.1-354.1
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    • 2002
  • Carbocyclic nucleosides are unique class in which a methylene group replaces the oxygen in the furan, which result in metabolic stability to endogenous phosphorylase. The biologically active natural carbocyclic nucleosides such as aristeromycin and neplanocin were found to possess interesting biological properties including antiviral and antitumor activity. (omitted)

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Hepatotoxic Effects of 1-Furan-2-yl-3-pyridin-2-yl-propenone, a New Anti-Inflammatory Agent, in Mice

  • Jeon, Tae-Won;Kim, Chun-Hwa;Lee, Sang-Kyu;Shin, Sil;Choi, Jae-Ho;Kang, Won-Ku;Kim, Sang-Hyun;Kang, Mi-Jeong;Lee, Eung-Seok;Jeong, Tae-Cheon
    • Biomolecules & Therapeutics
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    • v.17 no.3
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    • pp.318-324
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    • 2009
  • 1-Furan-2-yl-3-pyridin-2-yl-propenone (FPP-3) has recently been synthesized and characterized to have an anti-inflammatory activity through the inhibition of the production of nitric oxide. In the present study, adverse effects of FPP-3 on hepatic functions were determined in female BALB/c mice. When mice were administered with FPP-3 at 125, 250 or 500 mg/kg for 7 consecutive days orally, FPP-3 significantly increased absolute and relative weights of liver with a dose-dependent manner. In addition, FPP-3 administration dramatically increased the hepatotoxicity parameters in serum at 500 mg/kg, in association of hepatic necrosis. FPP-3 significantly induced several phase I enzyme activities. To elucidate the possible mechanism(s) involved in FPP-3 induced hepatotoxicity, we investigated the hepatic activities of free radical generating and scavenging enzymes and the level of hepatic lipid peroxidation. FPP-3 treatment significantly elevated the hepatic lipid peroxidation, measured as the thiobarbituric acid-reactive substance, and the activity of superoxide dismutase. Taken together, the present data indicated that reactive oxygen species might be involved in FPP-3-induced hepatotoxicity.

Inhibitory Effects of Propenone Derivatives on $NF-{\kappa}B$ activity and IL-8-Induced Monocyte Adhesion to Colon Epithelial Cells (Propenone 유도체의 $NF-{\kappa}B$ 활성 억제 및 IL-8 유도에 의한 단핵구의 장 상피세포 부착 억제 효과)

  • Park, Su-Young;Kim, Kyoung-Jin;Lee, Jong-Suk;Lee, Eung-Seok;Kim, Jung-Ae
    • YAKHAK HOEJI
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    • v.52 no.1
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    • pp.62-66
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    • 2008
  • In this study, we examined the inhibitory effects of propenone derivatives, 1,3-diphenyl-propenone (DPhP), 3-phenyl-1-thiophen-2-yl-propenone (PhT2P), 3-phenyl-1-thiophen-3-yl-propenone (PhT3P) and 1-furan-2-yl-3-phenyl-propenone (FPhP), on $TNF-{\alpha}$-induced nuclear factor (NF)-${\kappa}B$ activity and interleukin (IL)-8-induced monocyte adhesion to colon epithelial cells. 1-Furan-2-yl-3-pyridin-2-yl-propenone (FPP-3) that is previously reported as a $NF-{\kappa}B$ inhibitor suppressed $TNF-{\alpha}$-induced monocyte-epithelial cell adhesion in a concentration-dependent manner. The propenone derivatives, DPhP, PhT2P, PhT3P, FPhP, also inhibited $TNF-{\alpha}$-induced $NF-{\kappa}B$ activation in a similar degree to FPP-3. In a DPPH radical scavenging assay, none of the compounds showed DPPH radical scavenging activity, indicating that the inhibitory actions of the propenone derivatives on redox-sensitive $NF-{\kappa}B$ activity is not due to a simple free radical scavenging activity. In addition, the propenone derivatives also suppressed the IL-8-induced monocyte adhesion to colon epithelial cells. Furthermore, the effective concentrations of the propenone derivatives on both $NF-{\kappa}B$ activation as well as IL-8 induced monocyte-epithelial cell adhesion were 1000 times lower than 5-aminosalicylic acid (5-ASA), a clinically used drug for inflammatory bowel disease. These results suggest that the propenone derivatives may be a potential lead having a strong inhibitory activity against inflammatory cytokine-induced epithelial inflammation.

Occurrence of Off-Odor and Distribution of Thermophilic Bacteria from Rice and Cooked Rice Stored at Electric Rice Cooker (쌀과 취반백미의 고온성 세균 분포 및 이상취 발생)

  • 박석규;고용덕;권선화;손미예;이상원
    • Food Science and Preservation
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    • v.10 no.1
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    • pp.70-74
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    • 2003
  • The distribution of mesophilic and thermophilic bacteria in milled rice was not different according to growing land and variety of rice. However, The number of these bacteria were abundant in milled rice of lower milling degree or longer storage period. The growth of thermophilic bacteria in cooked rice of electric rice cooker was rapidly increased during storage of lower temperature below 75 $^{\circ}C$. Thermophilic bacteria were not appeared just after cooking. After cooked rice was stored far 18∼24 hon thermophilic bacterial growth was rapidly increased by changing spore to vegetative cell. The positive relation between cell number of thermophilic bacteria and occurrence of off-odor was slightly observed. The number of thermophilic bacteria in upper cooked rice of oven and was higher than those in inner and lower cooked rice. Major volatile compound of milled rice cooked and stored in electric rice cooker was hexanal oriented from rice. After long storage, it was confirmed that furan was major volatile compound as off-odor.

Synthesis of Renewable Jet Fuel Precursors from C-C Bond Condensation of Furfural and Ethyl Levulinate in Water

  • Cai, Chiliu;Liu, Qiying;Tan, Jin;Wang, Tiejun;Zhang, Qi;Ma, Longlong
    • Korean Chemical Engineering Research
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    • v.54 no.4
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    • pp.519-526
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    • 2016
  • Biomass derived jet fuel is proven as a potential alternative for the currently used fossil oriented energy. The efficient production of jet fuel precursor with special molecular structure is prerequisite in producing biomass derived jet fuel. We synthesized a new jet fuel precursor containing branched $C_{15}$ framework by aldol condensation of furfural (FA) and ethyl levulinate (EL), where the latter of two could be easily produced from lignocellulose by acid catalyzed processes. The highest yield of 56% for target jet fuel precursor could be obtained at the optimal reaction condition (molar ratio of FA/EL of 2, 323 K, 50 min) by using KOH as catalyst. The chemical structure of $C_{15}$ precursor was specified as (3E, 5E)-6-(furan-2-yl)-3-(furan-2-ylmethylene)-4-oxohex-5-enoic acid ($F_2E$). For stabilization, this yellowish solid precursor was hydrogenated at low temperature to obtain C=C bonds saturated product, and the chemical structure was proposed as 4-oxo-6-(tetrahydrofuran-2-yl)-3-(tetrahydrofuran-2-yl)-methyl hexanoic acid ($H-F_2E$). The successful synthesis of the new jet fuel precursors showed the significance that branched jet fuel could be potentially produced from biomass derived FA and EL via fewer steps.

Isolation and Structural Determination of Free Radical Scavenging Compounds from Korean Fermented Red Pepper Paste (Kochujang)

  • Chung, Jin-Ho;Shin, Heung-Chule;Cho, Jeong-Yong;Kang, Seong-Koo;Lee, Hyoung-Jae;Shin, Soo-Cheol;Park, Keun-Hyung;Moon, Jae-Hak
    • Food Science and Biotechnology
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    • v.18 no.2
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    • pp.463-470
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    • 2009
  • Sixteen antioxidative active compounds isolated from the EtOAc layer of MeOH extracts of kochujang, Korean fermented red pepper paste, were structurally elucidated as fumaric acid, methyl succinate, succinic acid furan-2-yl ester methyl ester (gochujangate, a novel compound), 2-hydroxy-3-phenylpropanoic acid, 3,4-dihydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 6,7-dihydroxy-2H-chromen-2-one (esculetin), caffeic acid, cis-p-coumaric acid, trans-p-coumaric acid, daidzin, genistin, apigenin 7-O-$\beta$-D-apiofuranosyl($1{\rightarrow}2$)-$\beta$-D-glucopyranoside, apigenin 7-O-$\beta$-Dglucopyranoside, and quercetin 3-O-$\alpha$-L-rhamnopyranoside by mass spectrometry (MS) and nuclear magnetic resonance (NMR) experiments. These compounds were analyzed for the first time as antioxidants from kochujang.

Structural and Property Changes in Glass-like Carbons Formed by Heat Treatment and Addition of Filler

  • Kim, Jangsoon;Kim, Myung-Soo;Hahm, Hyun-Sik;Lim, Yun-Soo
    • Macromolecular Research
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    • v.12 no.4
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    • pp.399-406
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    • 2004
  • Glass-like carbon precursors shrink significantly during curing and carbonization, which leads to crack formation and bending. Cured furan resin powder and ethanol were added to furan resin to diminish the weight loss, to suppress the shrinkage and bending, and to readily release the gases evolved during polymerization and curing. Curing and carbonization were controlled by pressure and slow heating to avoid damage to the samples. The effect of the filler and ethanol on the fabrication process was examined by measuring the properties of the glass-like carbon, such as the specific gravity, bending strength, electrical resistivity, and microstructural change. The specific gravities of the filler-added glass-like carbons were higher than those of the ethanol-added samples because of the formation of macropores from the vaporization of ethanol during the curing and polymerization processes. Although the ethanol-added glass-like carbons exhibited lower bending strengths after carbonization than did the filler-added samples, the opposite result was observed after aging at 2,600$^{\circ}C$. We found that the macropores created from ethanol were contracted and removed upon heat treatment. The electrical resistivity of the glass-like carbon aged at 2,600$^{\circ}C$ was lower than those of the samples carbonized at 1,000$^{\circ}C$. We attribute this phenomenon to the fact that aging at high temperature led to well-developed microstructures, the removal of macropores, and the reduction of the surface area.

Effect of Roasting Condition and Cold-pressed Flaxseed (Linum usitatissimum L.) oil on Fatty Acid Composition and Volatile Compound (볶음조건과 저온압착이 아마씨유(Linum usitatissimum L.)의 지방산 조성 및 휘발성 성분에 미치는 영향)

  • Won, Sae Bom
    • Journal of Convergence for Information Technology
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    • v.10 no.11
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    • pp.177-184
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    • 2020
  • The objective of this study was to investigate the effect of cold-pressed flaxseed oil through the roasting temperature (unroasted and roasted at 150℃ and 200℃) and time (10 and 20 min) on the chemical changes. Cold-pressed flaxseed oil extraction yield was calculated with respect to the roasted process and total phenolic content, fatty acid composition, and volatile compound were analyzed. The extraction yield was increased in the roasted oil compared to the unroasted oil. Total phenolic content was significantly higher in oil from the roasted at 150℃ for 20 min compared to other roasting condition. Fatty acid composition was not affected by the extraction process. The content of aldehyde, ketone, furan, and pyrazine was higher than in the roasted at 200℃ compared to the unroasted and roasted at 150℃. These findings suggest that cold-pressed flaxseed oil extracted from the roasted at 150℃ for 20 min may be considered acceptable for safe extraction process.