• Title/Summary/Keyword: BF-I

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X-ray and Spectroscopy Studies of Mercury (II) and Silver (I) Complexes of α-Ketostabilized Phosphorus Ylides (α-케토안정화된 일리드화 인의 수은(II) 및 은(I) 착물에 대한 X-선 및 분광학적 연구)

  • Karami, K.;Buyukgungor, O.;Dalvand, H.
    • Journal of the Korean Chemical Society
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    • v.55 no.1
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    • pp.38-45
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    • 2011
  • The complexation behavior of the $\alpha$-ketostabilized phosphorus ylides $Ph_3P$=CHC(O) $C_6H_4-X$ (X=Br, Ph) towards the transition metal ions mercury (II) and Silver (I) was investigated. The mercury(II) complex {$HgX_2$ [Y]} 2 ($Y_1$=4-bromo benzoyl methylene triphenyl phosphorane; X=Cl(1), Br(2), I(3), $Y_2$=4-phenyl benzoyl methylene triphenyl phosphorane; X=Cl(4), Br(5), I(6)) have been prepared from the reaction of $Y_1$ and $Y_2$ with $HgX_2$ (X=Cl, Br, I) respectively. Silver complexes [$Ag(Y_2)_2]$ X(X=$BF_4$(7), OTf(8)) of the $\alpha$-keto-stabilized phosphorus ylides ($Y_2$) were obtained by reacting this ylide with AgX (X=$BF_4$, OTf) in $Me_2CO$. The crystal structure of complexes (1) and (4) was discussed. These reactions led to binuclear complexes C-coordination of ylide and trans-like structure of complexes $[Y_1HgCl_2]_2$. $CHCl_3$ (1) and $[Y_2HgCl_2]_2$ (4) is demonstrated by single crystal X-ray analyses. Not only all of complexes have been studied by IR, $^1H$ and $^{31}P$ NMR spectroscopy, but also complexes 1-3 have been characterized by $^{13}$CNMR.

Inhibitory Effect of Benzofuran Compound on Cyclooxygenase

  • Min, Kyung-Rak;Ahn, Ki-Young;Chung, Eun-Yong;Lee, Yong-Rok;Kim, Yeong-Shik;Kim, Young-Soo
    • Natural Product Sciences
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    • v.10 no.6
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    • pp.315-320
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    • 2004
  • Alpha-viniferin was previously isolated as a cyclooxygenase (COX)-2 inhibitor from Carex humilis (Cyperaceae) and is an oligomeric stilbene compound with benzofuran (BF) moieties in its chemical structure. In the present study, a chemically synthetic BF compound, named as 3,3-dimethyl-2,3,4,6,7,8,9,10,11,12,13,14,15,16,17,18-hexadecahydro-1H-benzo[b] cyclopentadeca[d]furan-1-one, was discovered to inhibit bacterial lipo polysaccharide (LPS)-induced prostaglandin $E_2$ $(PGE_2)$ production in macrophages RAW 264.7. The BF compound exhibited a selectively preferred inhibitory effect on COX-2 activity over COX-1 activity. Furthermore, BF compound inhibited LPS-induced COX-2 expression at transcription level. As a down-regulatory mechanism of COX-2 expression shown by BF compound, suppression of nuclear factor $(NF)-{\kappa}B$ activation has been demonstrated. BF compound inhibited LPS-induced $NF-{\kappa}B$ transcriptional activity and nuclear translocation of $NF-{\kappa}B$ p65, in parallel, but did not affect LPS-induced degradation of inhibitory ${\kappa}B{\alpha}$ protein $(I{\kappa}B{\alpha})$. Taken together, anti-inflammatory effect of BF compound on $PGE_2$ production was ascribed by its down-regulatory action on LPS-induced COX-2 synthesis in addition to inhibitory action on enzyme activity of COX-2.

Thermally Induced Cationic Polymerization of Glycidyl Phenyl Ether Using Novel Xanthenyl Phosphonium Salts

  • Gupta, Mukesh Kumar;Singh, Raj Pal
    • Macromolecular Research
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    • v.17 no.4
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    • pp.221-226
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    • 2009
  • The present study firstly describes the synthesis of novel, thermo-latent initiators based on xanthenyl phosphonium salts with different counter anions and phosphine moieties and secondly examines their efficiency in the bulk polymerization of glycidyl phenyl ether(GPE). The polymerization was performed with phosphonium salt initiators($I_{SbF6}$, $I_{PF6}$, $I_{AsF6}$ and $I_{BF4}$) at ambient temperature to $200^{\circ}C$ for 1 h. The order of initiator activity was $I_{SbF6}>I_{PF6}>I_{AsF6}>I_{BF4}$. To examine the effect of the phosphine moiety on the initiator activity, polymerization was carried out with $I_{SbF6}(Ph_{3}P)$ and $II_{SbF6}(Bu_{3}P)$ at ambient temperature to $170^{\circ}C$ for 1 h. The order of reactivity was $I_{SbF6}>II_{SbF6}$. In general, the conversion percentage increased with increasing polymerization temperature. The thermal stability of these salts was measured by thermo gravimetric analysis(TGA). The solubility of phosphonium salts in various organic solvents and epoxy monomers was also investigated.

Ensiling Characteristics and the In situ Nutrient Degradability of a By-product Feed-based Silage

  • Kim, Y.I.;Oh, Y.K.;Park, K.K.;Kwak, W.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.2
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    • pp.201-208
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    • 2014
  • This study was conducted to evaluate the ensiling characteristics and the in situ degradability of a by-product feed (BF)-based silage. Before ensilation, the BF-based mixture was composed of 50% spent mushroom substrate, 21% recycled poultry bedding, 15% ryegrass straw, 10.8% rice bran, 2% molasses, 0.6% bentonite, and 0.6% microbial inoculant on a wet basis and ensiled for up to 4 weeks. The BF-based silage contained on average 39.3% moisture, 13.4% crude protein (CP), and 52.2% neutral detergent fiber (NDF), 49% total digestible nutrient, and 37.8% physically effective $NDF_{1.18}$ on a dry matter (DM) basis. Ensiling the BF-based silage for up to 4 weeks affected (p<0.01) the chemical composition to a small extent, increased (p<0.05) the lactic acid and $NH_3$-N content, and decreased (p<0.05) both the total bacterial and lactic acid bacterial counts from $10^9$ to $10^8$ cfu/g when compared to that before ensiling. These parameters indicated that the silage was fermented and stored well during the 4-week ensiling period. Compared with rice or ryegrass straws, the BF-based silage had a higher (p<0.05) water-soluble and filterable fraction, a lower insoluble degradable DM and CP fraction (p<0.05), a lower digestible NDF (p<0.05) fraction, a higher (p<0.05) DM and CP disappearance and degradability rate, and a lower (p<0.05) NDF disappearance and degradability rate. These results indicated that cheap, good-quality BF-based roughage could be produced by ensiling SMS, RPB, rice bran, and a minimal amount of straw.

Bupleurum falcatum Prevents Depression and Anxiety-Like Behaviors in Rats Exposed to Repeated Restraint Stress

  • Lee, Bom-Bi;Yun, Hye-Yeon;Shim, In-Sop;Lee, Hye-Jung;Hahm, Dae-Hyun
    • Journal of Microbiology and Biotechnology
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    • v.22 no.3
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    • pp.422-430
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    • 2012
  • Previous studies have demonstrated that repeated restraint stress in rodents produces increases in depression and anxiety-like behaviors and alters the expression of corticotrophin-releasing factor (CRF) in the hypothalamus. The current study focused on the impact of Bupleurum falcatum (BF) extract administration on repeated restraint stress-induced behavioral responses using the forced swimming test (FST) and elevated plus maze (EPM) test. Immunohistochemical examinations of tyrosine hydroxylase (TH) expression in rat brain were also conducted. Male rats received daily doses of 20, 50, or 100 mg/kg (i.p.) BF extract for 15 days, 30 min prior to restraint stress (4 h/day). Hypothalamic-pituitary-adrenal axis activation in response to repeated restraint stress was confirmed base on serum corticosterone levels and CRF expression in the hypothalamus. Animals that were pre-treated with BF extract displayed significantly reduced immobility in the FST and increased open-arm exploration in the EPM test in comparison with controls. BF also blocked the increase in TH expression in the locus coeruleus of treated rats that experienced restraint stress. Together, these results demonstrate that BF extract administration prior to restraint stress significantly reduces depression and anxiety-like behaviors, possibly through central adrenergic mechanisms, and they suggest a role for BF extract in the treatment of depression and anxiety disorders.

Methanolic extract from the root of Bupleuri falcatum L. attenuates cocaine-induced c-Fos expression in rat brain. (시호 메탄올 추출물이 코카인 약물중독에 의한 흰쥐 뇌의 c-Fos 발현에 미치는 영향)

  • Choi, Seong-Hun;Ku, Sae-Kwang;Han, Chang-Hyun;Yang, Chae-Ha
    • Korean Journal of Oriental Medicine
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    • v.16 no.1
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    • pp.141-147
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    • 2010
  • Objectives : The aim of present study is to examine the effect of methanolic extract from the root of Bupleurum falcatum L. (BF) on acute cocaine-induced c-Fos expression in the rat caudate putamen (CPu), a major dopaminergic terminal. Methods : Male Sprague-Dawley rats were subjected to an intraperitoneal injection with either cocaine hydrochloride (20 mg/kg) or saline 30 min after an administration of either extract of BF (100 mg/kg, i.p.) or vehicle. Animals were sacrificed 2 hr after treatment with cocaine or saline for immunohistochemistry. Quantification of brain slices was examined for c-Fos positive nuclei using light microscopy. Results : Pretreatment with BF significantly attenuated cocaine-induced c-Fos expression in the rat CPu. Conclusions : This finding suggests that BF has the inhibitory effect on cocaine-induced c-Fos expression in the rat CPu via possibly modulating the activities of central dopaminergic systems.

Electrochemical Studies of Lithium Ion Battery Current Collector in the Aprotic Electrolytes: I. Al Current Collector (비수용성 전해질내 리튬이온전지용 집전체의 전기화학적 특성 연구: I. Al 집전체)

  • Park, Heai-Ku
    • Applied Chemistry for Engineering
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    • v.10 no.4
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    • pp.620-627
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    • 1999
  • Electrochemical properties of the Al current collector being used in lithium ion batteries have been studied in the 4 different aprotic electrolytes(1 M $LiBF_4$ EC : DMC, 1 M $LiBF_4$ EC : EMC. 1 M $LiPF_6$ EC : DMC. 1 M $LiPF_6$ EC : EMC) employing cyclic voltammetry and impedance measurement. Al electrode showed a wide range of the electrochemical window(0.5~4.1 V vs. $Li/Li^{+}$). However, solid interfacial materials has been formed on the Al surface due to reduction of impurities($H_2O$, $O_2$, etc), lithium salts, and electrolytes at low applied potentials, and aluminum oxides in the highly oxidizing potential as well. Especially, Al current collector was susceptible to localized in consequence of impurities in electrolytes.

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Effects of Pre-slaughter Fasting and Chiller Ageing on Objective Meat Quality in Longissimus Dorsi, Biceps Femoris, and Triceps Brachii Muscles of Korean Native Black Pigs (도축전 절식과 냉장숙성이 재래돼지 Longissimus Dorsi, Biceps Femoris와 Triceps Brachii의 육질에 미치는 영향)

  • Hwang, I.H.;Park, B.Y.;Cho, S.H.;Kim, M.J.;Lee, J.M.
    • Journal of Animal Science and Technology
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    • v.46 no.3
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    • pp.405-414
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    • 2004
  • This study evaluated the effects of preslaughter feed withdrawal and chiller ageing on objective meat quality traits in longissimus dorsi (LD), biceps femoris(BF), and triceps brachii(TB) muscles of Korean native black pigs. Twenty males were assigned into a 2(pre-slaughter feeding) ${\times}$ 2(pre-slaughter stress) ${\times}$ 4(chiller ageing) factorial. Pre-slaughter fasting for 18 h resulted in significantly(P < 0.05) higher pHs at 1.5 h for both LD and BF. On the other hand, muscle temperature did not differ between the fasted and fed animals. The result implied that pigs with different pre-slaughter feedings experienced different pH-temperature profiles during rigor development. This was reflected by the significan(P < 0.05) increase in cooking loss and hunter $L^*$ for LD of the fed pigs. However, WB-shear force of LD was not affected by the treatment. Furthermore, objective meat quality of BF and TB did not differ between the treatments. Hunter $L^*$ value and cooking loss for LD were constant for 7 d, followed by a significant(P < 0.05) increase at 14 d. BF and TB had significantly(P < 0.05) higher hunter $L^*$ value and cooking loss at 14 d than at 1 d. Significant(P < 0.05) linear reductions in LD WB-shear force took place from 1 to 7 d, while BF and TB WB-shear forces were significantly (P < 0.05) reduced at 14 d. Simple correlation for WB-shear force between LD and BF, and between LD and TB indicated that 6 kg of shear force for LD was equivalent to approximately 3.5 and 6 kg for TB and BF, respectively. On the basis of the current result, feeding until the morning of slaughter appeared to contribute to favourable meat color for LD. However, negative effect on palatability due to increase in cooking loss should be taken into account. A 7-d chiller ageing was likely the best practice for LD, while TB appeared not to require chiller ageing. A 14-d ageing could improve the tenderness of BF, but could likely reduce juiciness.

Synthesis and Application of New Type Organometallic Catalyszt -Synthesis of Bisphosphonite-Rhodium Complexes- (입체선택적 유기합성반응을 위한 새로운 촉매 합성과 이의 응용 -Bisphosphonite-Rhodium 촉매합성-)

  • Kyung, Suk-Hun
    • Applied Biological Chemistry
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    • v.40 no.6
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    • pp.588-592
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    • 1997
  • The new type ligand, bisphosphonites, were easily prepared through ligand exchange reaction of bis (diethylamino)phosphine with diols. These bisphosphonites reacted with $(COD)^2Rh^+BF_4\;^-$ to corresponding bisphosphonite-rhodium(I) comlexes, of which X-ray crystallography was for the first time investigated. This organometallic compound was applicated in hydroformylation reaction as catalyst, and proved to be very effective one.

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