• Title/Summary/Keyword: 리간드 효과

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Adamantyl-based N-arylamide as a Novel Series of Androgen Receptor Antagonists (아다만틸을 기반한 N-아릴아미드 신규 안드로겐 수용체 길항제)

  • Woo, Byoung Young;Shin, Song Seok;Hong, Yong Deog;Joo, Yung Hyup;Jeong, Yeonsu;Lee, Beom-Jin;Kim, Soo-Dong
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.46 no.1
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    • pp.43-47
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    • 2020
  • A novel series of adamantyl derivatives of N-aryl amides as androgen receptor antagonists were synthesized and their anti-androgenic activities were evaluated. The N-aryl amides containing adamantyl derivatives had more activity than those lacking adamantyl substitutions. The synergistic effect of bulkiness of the adamantyl group and modulation of electron density on the aromatic ring by pendant groups was crucial to the potent antagonism. Molecular modeling studies were performed to elucidate the interactions between ligands and receptors.

Inhibitory Effects of Copper on the Anaerobic Degradation of Propionate (프로피온산의 혐기성 분해시 구리의 저해 효과)

  • Shin, Hang-sik;Lee, Chae-young
    • Journal of the Korea Organic Resources Recycling Association
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    • v.7 no.2
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    • pp.25-34
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    • 1999
  • The effects of copper on the anaerobic degradation of propionate were studied using anaerobic batch reactors. The apparent inhibitory effects of copper on the anaerobic degradation of propionate could be observed from behaviors of intermediates, ultimate methane yield(UMY) and specific methanogenic activity(SMA) There was little inhibition at the concentration of $2.5mg\;Cu^{2+}/L$. Beyond this concentration, the inhibitory effects increased with increasing dose of coppers. The 50% inhibition of UMY and SMA occurred at copper dosage of 33.8 and $24.1mg\;Cu^{2+}/gVSS$, respectively. The inhibitory effect based on the UMY was gradually reduced with the operation time dueprobably to the acclimation of microorganisms and/or binding of the added copper by ligands(and possibly ion exchange sites)contained on the cell membrane and extracellular polymer matrix whereas it based on the SMA might exclude the this phenomena. Therefore, the methodology for interpretation of inhibition data based on the SMA was more accurated than the UMY. There was no inhibitory effect in batch reactors supplemented with sulfate due to an antagonistic action of the sulfate reducing bacteria. Propionate degradation was initially retarded for copper inhibited samples but it gradually degraded afterward. Based on the mass removal considering take into account the propionate to acetate conversion, propionate degradation may appeal more affected than acetate. This result revealed that the hydrogenotrophic methanogens were the most affected by copper.

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Ciglitazone, in Combination with All trans Retinoic Acid, Synergistically Induces PTEN Expression in HL-60 Cells (백혈병세포에서 PTEN 발현에 대한 Ciglitazone과 retinoic Acid의 항진 작용)

  • Lee Seung-Ho;Park Chul-Hong;Kim Byeong-Su
    • Journal of Food Hygiene and Safety
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    • v.21 no.3
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    • pp.171-180
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    • 2006
  • Peroxisome proliferatorr-activated receptor-gamma $(PPAR{\gamma})$ must form a heterodimer with the retinoid-X receptor (RXR) to bind DNA, and its transcriptional activity is thought to be maximized by ligands specific for either receptor. Activated $(PPAR{\gamma})$ and $(PPAR{\gamma})$ ligands may influence tumor growth through regulation of the tumor suppressor PTEN. Our aim in this study was to determine whether co-stimulation with the $(PPAR{\gamma})$ ligand, ciglitazone, and RXR ligand can synergistically upregulate PTEN in human acute promyelocytic leukemia (APL) cells and consequently potentate the inhibition of cell growth and cell cycle progression of these cells. Human leukemia cell line, HL-60 cells were exposed to all-trans-retinol and ciglutazone. The PTEN expression was measured as the level of PTEN mRNA expression by RT-PCR and as the level of PTEN expression by western blot analysis. Cell cycle analysis was carried out by a propidium iodide (PI) staining method and analyzed with a FACScan. The $(PPAR{\gamma})$ ligand, ciglitazone, and the RXR ligand, retinoic acid, upregulated PTEN expression by HL-60 cells in time- and dose-dependent manners, respectively. This was significantly enhanced by a combination of both ciglitazone and retinoic acid. Moreover, these compounds synergistically induced arrests of both cell growth and the $G_l$ phase of the cell cycle. Thus, the activation of the $(PPAR{\gamma})$:RXR heterodimer may represent a regulatory pathway for human leukemia cells and there may be important roles for $(PPAR{\gamma})$ and RXR ligands in prophylactic and therapeutic approaches fur controlling leukemia through the upregulation of PTEN.

전이금속 (Ru$^{3+}$, Ni$^{2+}$, Cu$^{2+}$, Pd$^{2+}$)-Polyaza(N$_4$) 착물의 합성과 올레핀 산화반응에 대한 촉매적 활성

  • Park, Yu Cheol;Kim, Seong Su;Na, Hun Gil;Lee, Dong Cheol;Sin, Sang Hui;Byeon, Jong Cheol
    • Journal of the Korean Chemical Society
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    • v.38 no.4
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    • pp.295-301
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    • 1994
  • The Ru(Ⅲ), Ni(Ⅱ), Cu(Ⅱ), and Pd(Ⅱ) complexes of N$_4$-polydentate ligands(meso-Me$_6$-[14]-ane, rac-Me$_6$-[14]-ane, and cyclam) have been prepared and their catalytic activity and selectivity in the oxidation of olefins in the presence of oxidant such as NaOCl, H$_2$O$_2$, t-BuOOH, and PhIO studied. The oxidations of cyclohexene, 1-hexene, cyclooctene, 1-octene, and styrene as substrates have been investigated gas chromatographically. The Ru(Ⅲ)-N$_4$ complexes showed high selectivity for epoxide in the catalyzed oxidation of olefins with NaOCl. The catalytic activities of Ru(Ⅲ)-N$_4$ complexes were discussed in terms of the flexibility of N$_4$-polydentate ligands, the Ru(Ⅲ)-Cl bond interaction and the steric effect of oxidants. The oxidation of 1-octene using PhIO as oxidant was carried out to verify. The Pd(Ⅱ) complex turned out to be more active catalyst than the Ni(Ⅱ) complexes.

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Syndiotactic Polymerization of Styrene Catalyzed by Dinuclear (Cyclopentadienyl) (Aryloxy) Titanium(IV) Complexes with Polymethylene Bridge (폴리메틸렌 가지로 연결된 이핵 아릴옥시 티타늄 화합물을 이용한 스티렌의 신디오탁틱 중합)

  • Kum Don-Ho;Jung Woosung;Kim Kyungsik;Noh Seok Kyun;Lee Dong-Ho;Lyoo Won Seok
    • Polymer(Korea)
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    • v.30 no.1
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    • pp.64-69
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    • 2006
  • A series of dinuclear half-sandwich titanium complexes with aryloxy substituent at titanium$[(\eta^5-cyclopentadienyl)(aryloxy)TiCl_2]_2[(CH_2)_n]$ (n=3, n=6, n=9) have been successfully synthesized and their styrene polymerization properties have been investigated. All complexes are characterized by $^1H\;NMR,\;^{13}C\;NMR$, elemental analysis, and mass spectrometry. In order to examine the catalytic properties of the dinuclear complexes styrene polymerization has beer conducted in the presence of MMAO. It was found that (i) all the prepared complexes were very effective catalyst for the production of SPS (syndiotactic polystyrene), (ii) the complex with the longest bridge between the two active sites exhibited greatest catalytic activity among the three catalysts, but produced SPS with the smallest molecular weight, (iii) the activities of dinuclear half-titanocens with aryloxy substitution at titanium metal were greater than those of the chloride substituted compounds. These results indicate that not only the nature of the bridge between the two active sites but also the property of substituents at the metal exert a significant influence on the polymerization behaviors of the dinuclear half-titanocene.

Electrocatalytic Effect of Dioxygen Reduction at Glassy Carbon Electrode Modified with Schiff Base Co(II) Complexes (Schiff Base Co(II) 착물이 변성된 유리질 탄소전극에서 산소 환원의 전기촉매 효과)

  • Seong, Jeong-Sub;Chae, Hee-Nam;Choi, Yong-Kook
    • Analytical Science and Technology
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    • v.11 no.6
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    • pp.460-468
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    • 1998
  • Schiff base ligands such as $SOPDH_2$, $SNDH_2$, $EBNH_2$, and $PBNH_2$ and their Co(II) complexes such as [$Co(II)(SND)(H_2O)_2$], [$Co(II)(SOPD)(H_2O)_2$], [$Co(II)(EBN)(H_2O)$], and [$Co(II)(PBN)(H_2O)$] have been synthesized. The mole ratio of Shiff base ligand to cobalt(II) for the Co(II) complexes was found to be 1:1. Also these complexes have been configurated with hexa-coordination. Reduction of dioxygen was investigated by cyclic voltammetry at glassy carbon electrodes modified with Schiff base Co(II) complexes in 1 M KOH aqueous solution. At modified glassy carbon electrode with Schiff base Co(II) complexes, reduction peak current of oxygen was increased and peak potential was shifted to more positive direction compared to bare glassy carbon electrode. The electrokinetic parameters such as number of electron and exchange rate constant were calculated from the results of cyclic voltammogrms. The reduction of dioxygen at glassy carbon electrode has been $2e^-$ reaction pathway. Exchange rate constant at glassy carbon electrode modified with Co(II) complexes was increased 2~10 times compared to bare electrode.

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Optical Resolution of Free Amino Acids with Addition of Copper(II) Chelates in a Reversed-Phase Liquid Chromatography (구리(II) 킬레이트의 첨가에 의한 자유아미노산 광학이성질체의 역상 액체크로마토그래피적 분리)

  • Sun Haing Lee;Tae Sub Oh;Hong Yeup An;Kyung Sug Park;Sang Oh OH
    • Journal of the Korean Chemical Society
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    • v.36 no.6
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    • pp.879-888
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    • 1992
  • Separation of the optical isomers of free amino acids by a reversed phase high performance liquid chromatography has been studied by adding a copper(II) complex of L-proline or L-proline derivatives (hydroxy-L-proline, N-benzyl-L-proline, p-xylenyl-L-proline, p-xylenyl-hydroxy-L-proline) in the mobile phase. An OPA postcolumn detection system was used for the detection of amino acids. The chromatographic properties for the free amino acids were discussed in terms of the pH, the kinds and concentration of chelate or organic modifier. The retention behaviors of the free amino acids were considerably different from, those of DNS-amino acids or DABS-amino acids. The enantioselectivity of the free amino acids was better than that of derivatized amino acids. The enantioselectivity between the optical isomers observed by use of the Cu(II)-p-xylenyl-L-proline chiral cheleate was the best among the several copper(II) chelate. A separation mechanism could be illustrated not only by the hydrophobic interaction of the diastereomer with stationary phase but also by the steric effect of the ligand exchange reaction between the free-amino acids and copper chelate.

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Studies on the Effect of Picolines on the Stereochemistry of Lanthanide(III) Nitrate Coordination Compounds of 4[N-Furfural)amino]antipyrine Semicarbazone and Antibacterial Activities (4[N-Furfural)amino]antipyrine Semicarbazone의 질산 란탄(III) 배위화합물의 입체화학에 미치는 Picolines의 영향과 항박테리아 활성)

  • Agarwal, Ram K.;Agarwal, Himanshu;Prasad, Surendra;Kumar, Anil
    • Journal of the Korean Chemical Society
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    • v.55 no.4
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    • pp.594-602
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    • 2011
  • The effect of ${\alpha}$-, ${\beta}$- and ${\gamma}$-picolines on the stereochemistry of the coordination compounds of lanthanide(III) nitrates derived from 4[N-(furfural)amino]antipyrine semicarbazone (FFAAPS) has been studied. The general composition of the present coordination compounds is [Ln(FFAAPS)$(NO_3)_3$Pic] (Ln=La, Pr, Nd, Sm, Gd, Tb, Dy or Ho and Pic=${\alpha}$-, ${\beta}$- or ${\gamma}$-picolines). All these coordination compounds have been characterized by elemental analyses, molecular weight, molar conductance, magnetic susceptibility, infrared and electronic spectra. The infrared studies suggest that the FFAAPS behaves as a neutral tridentate ligand with N, N, O donor while ${\alpha}$-, ${\beta}$- or ${\gamma}$-picoline is coordinated to the lanthanide(III) ions via heterocyclic N-atom. Nitrates are bicovalently bonded in these compounds. From the electronic spectral data, nephelauxetic effect (${\beta}$), covalence factor ($b^{1/2}$), Sinha parameter (${\delta}%$) and the covalence angular overlap parameter (${\eta}$) have been calculated. Thermal stabilities of these complexes have been studied by thermogravimetric analysis. The coordination number of lanthanide(III) ions in the present compound is found to be ten. The antibacterial studies screening of the primary ligand FFAAPS and the complexes showed that the present complexes have moderate antibacterial activities.

A Study on the Elution Behavior of some Metal-N-Alkylisonitrosoacetylacetone imine Chelates by Reversed Phase High Performance Liquid Chromatography (역상 액체 크로마토그래피에 의한 몇 가지 금속-N-Alkylisonitrosoacetylacetone imine 킬레이트의 용리거동에 관한 연구)

  • Kim, Yong Jun;Kewon, Ji Hae;Lee, Won
    • Analytical Science and Technology
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    • v.5 no.1
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    • pp.63-71
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    • 1992
  • Liquid chromatographic behavior of Pd(II), Ni(II) and Co(III) in N-Alkylisonitrosoacetylacetone imine(HIAA-NR) chelates was investigated by reversed phase high perfomance liquid chromatography. The optimum conditions for the separation of IAA-NR-metal chelates were examined respect to the flow rate and mobile phase strength. The metal-N-Alkylisonitrosoacetylacetone imine chelates in solution were successfully separated on Novapak $C_{18}$ column using acetonitrile/water mixture as mobile phase. The elution order of chelates is methyl>ethyl>propyl>butyl as N-alkyl group for ligand is varied. It was found that all IAA-NR-metal chelates were eluted in an acceptable range of capacity factor value($0{\leq}log\;k^{\prime}{\leq}1$). The dependence of log k' on the volume fraction of water in the binary mobile phase was examined. Also, the dependence of k' on the liquid-liquid extraction distribution ratio(Dc) in acetonitrile-water-alkane extraction system was investigated for IAA-NR-metal chelate. Both kinds of dependence are linear, which suggests that the retention of the electroneutral metal chelates on Novapak $C_{18}$ column is largely due to the hydrophobic effect.

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Cytotoxic Effects of Some Transition Metals, Nickel(II), Copper(II) and Zinc(II), with 3.6-bis(2'-pyridyl)pyridazines Complexes (몇 가지 전이금속, Ni(II), Cu(II) 및 Zn(II) 3,6-bis(2'-pyridyl)pyridazine 착 화합물들의 세포 독성효과)

  • Kwon, Byung-Mok;Lee, Chong-Ock;Choi, Sang-Un;Sung, Nack-Do
    • Applied Biological Chemistry
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    • v.49 no.1
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    • pp.21-24
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    • 2006
  • A series of cytotoxic activities $(ED_{50})$ in vitro against six human cancers (lung cancer, uterine cancer, skin cancer, brain cancer, colon cancer and adenocarcinoma) and their seventeen cell lines of 3,6-bis(2'-pyridyl)pyridazine, 1, 3,6-bis-(6'-methyl-2'-pyridyl)pyridazine, 2 and their transition metal, Ni(II), Cu(II) and Zn(II) complexes, $3{\sim}6$ were measured. Particularly, the results revealed that the cytotoxic activities against the brain cancer cell line (SNB-19) and the colon cancer cell line (SW62) of bis- [3,6-bis-(6'-methyl-2'-pyridyl)pyridazine-$k^2N^2,N^3$]chlorocopper(II)perchlorate, 4 were shown to be higher than that of the first generation anticancer agent, Cis-platin.