• Title/Summary/Keyword: 2a

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No Role of Protected Region B of Human Cytochrome P4501A2 Gene (CYP1A2) As an AP-1 Response Element

  • Chung, In-Jae;Jung, Ki-Hwa
    • Archives of Pharmacal Research
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    • v.25 no.3
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    • pp.375-380
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    • 2002
  • Cytochrome P4501A2 (CYP1A2) is a member of the cytochrome P450 family of isozymes involved in the phase I drug metabolism of vertebrates. CYP1A2 is responsible for the activation of a number of aromatic amines to mutagenic and carcinogenic forms. Thus, the level of CYP1A2, which varies among different populations, may determine an individual's susceptibility to these chemicals. We have previously reported on the importance of a cis element named PRB (protected region B) in the regulation of human Cytochrome P4501A2 (CYP1A2) gene, which appeared to act as a positive regulatory element. Closer examination of the PRB sequence (-2218 to -2187 bp) revealed a putative AP-1 binding site, TGACTAA, at -2212 bp (Chung and Bresnick, 1997). To elucidate the role of AP-1 in CYP1A2 regulation, we transiently overexpressed c-Jun and c-Fos transcription factors in human hepatoma HepG2 cells, and examined their influence on the CYP1A2 promoter activity by reporter gene assays. Cotransfection of the c-Jun and the c-Fos expression vectors increased the induced transactivation by five to six fold from the CYP1A2 promoter constructs. However, deletion of the PRB element did not affect the degree of activation by the c-Jun and the c-Fos. Therefore, it is unlikely that the c-Jun and the c-Fos activate the CYP1A2 promoter through this AP-1 consensus-like sequence in the PRB region.

Synthesis and Crystal Structures of Copper(II) Complexes with Schiff Base Ligands: [Cu2(acpy-mdtc)2(HBA)(ClO4)]·H2O and [Cu2(acpy-phtsc)2(HBA)]·ClO4

  • Koo, Bon Kweon
    • Bulletin of the Korean Chemical Society
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    • v.34 no.11
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    • pp.3233-3238
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    • 2013
  • Two new Cu(II) complexes, $[Cu_2(acpy-mdtc)_2(HBA)(ClO_4)]{\cdot}H_2O$ (1) (acpy-mdtc- = 2-acetylpyridine S-methyldithiocarbamate and $HBA^-$ = benzilic acid anion) and $[Cu_2(acpy-phtsc)_2(HBA)]{\cdot}ClO_4$ (2) (acpy-$phtsc^-$ = 2-acetylpyridine 4-phenyl-3-thiosemicarbazate) have been synthesized and characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, and single crystal X-ray diffraction. The X-ray analysis reveals that the structures of 1 and 2 are dinuclear copper(II) complexes bridged by two thiolate sulfur atoms of Schiff base ligand and bidentate bridging $HBA^-$ anion. For 1, each of the two copper atoms has different coordination environments. Cu1 adopts a five-coordinate square-pyramidal with a $N_2OS_2$ donor, while Cu2 exhibits a distorted octahedral geometry in a $N_2O_2S_2$ manner. For 2, two Cu(II) ions all have a five-coordinate square-pyramidal with a $N_2OS_2$ donor. In each complex, the Schiff base ligand is coordinated to copper ions as a tridentate thiol mode.

Synthesis and Cation Binding Properties of Triester Calix[4]arenes and Calix[4]quinones

  • 남계천;강성옥;전종철
    • Bulletin of the Korean Chemical Society
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    • v.18 no.10
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    • pp.1050-1052
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    • 1997
  • The complexes M(CO)4-1,2-(PPh2)2-1,2-C2B10H10 (M=Cr 2a, Mo 2b, W 2c) have been prepared in good yields from readily available bis-diphenylphosphino-o-carboranyl ligand, closo-1,2-(PPh2)2-1,2-C2B10H10 (1), by direct reaction with Group Ⅵ metal carbonyls. The infrared spectra of the complexes indicate that there is an octahedral disposition of chelate bis-diphenylphosphino-o-carboranyl ligand around the metal atom. The crystal structure of 2a was determined by X-ray diffraction. Complex 2a crystallizes in the monoclinic space group P21/n with cell parameters a = 12.2360(7), b = 17.156(1), c = 16.2040(6) Å, V = 3354.1(3) Å3, and Z =4. Of the reflections measured a total of 2514 unique reflections with F2 > 3σ(F2) was used during subsequent structure refinement. Refinement converged to R1 = 0.066 and R2 = 0.071. Structural studies showed that the chromium atom had a slightly distorted pseudo-octahedral configuration about the metal center with two phosphine groups of o-carborane occupying the equatorial plane cis-orientation to each other. These metal carbonyl complexes are rapidly converted to the corresponding metal carbene complexes, [(CO)3M=C(OCH3)(CH3)]-1,2-(PPh2)2-1,2-C2B10H10 (M= Cr 3a, Mo 3b, W 3c), via alkylation with methyllithium followed by O-methylation with CF3SO3CH3.

Embedding a Mesh of Size 2n ×2m Into a Twisted Cube (크기 2n ×2m인 메쉬의 꼬인 큐브에 대한 임베딩)

  • Kim, Sook-Yeon
    • The KIPS Transactions:PartA
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    • v.16A no.4
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    • pp.223-226
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    • 2009
  • The twisted cube has received great attention as an interconnection network of parallel systems because it has several superior properties, especially in diameter, to the hypercube. It was recently known that, for even m, a mesh of size $2{\times}2^m$ can be embedded into a twisted cube with dilation 1 and expansion 1 and a mesh of size $4{\times}2^m$ with dilation 1 and expansion 2 [Lai and Tsai, 2008]. However, as we know, it has been a conjecture that a mesh with more than eight rows and columns can be embedded into a twisted cube with dilation 1. In this paper, we show that a mesh of size $2^n{\times}2^m$ can be embedded into a twisted cube with dilation 1 and expansion $2^{n-1}$ for even m and with dilation 1 and expansion $2^n$ for odd m where $1{\leq}n{\leq}m$.

NF-Y binds to both G1- and G2-specific cyclin promoters; a possible role in linking CDK2/Cyclin A to CDK1/Cyclin B

  • Chae, Hee-Don;Kim, Jung-Bin;Shin, Deug-Y.
    • BMB Reports
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    • v.44 no.8
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    • pp.553-557
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    • 2011
  • We previously reported that CDK2/Cyclin A can phosphorylate and activate the transcription factor NF-Y. In this study, we investigated a potential regulatory role for NF-Y in the transcription of Cyclin A and other cell cycle regulatory genes. Gel-shift assays demonstrate that NF-Y binds to CCAAT sequences in the Cyclin A promoter, as well as to those in the promoters of cell cycle G2 regulators such as CDC2, Cyclin B and CDC25C. Furthermore, expression of Cyclin A increases NF-Y's affinity for CCAAT sequences in the CDC2 promoter; however, Cyclin A's induction of CDC2 transcription is antagonized by p21, an inhibitor of CDK2/Cyclin A. These results suggest a model wherein NF-Y binds to and activates transcription from the Cyclin A promoter, increasing cellular levels of Cyclin A/CDK2 and potentiating NF-Y's capacity for transcriptional transactivation, and imply a positive feedback loop between NF-Y and Cyclin A/CDK2. Our findings are additionally indicative of a role for Cyclin A in activating Cyclin B/CDK1 through promoting NF-Y dependent transcription of Cyclin B and CDC2; NF-Y mediated crosstalk may therefore help to orchestrate cell-cycle progression.

Synthesis and Biological Evaluation as a Potential Antifungal Allylamine Derivatives (항진균 알릴아민 유도체의 합성과 생물학적 평가)

  • 정병호;정순영
    • YAKHAK HOEJI
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    • v.48 no.4
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    • pp.254-260
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    • 2004
  • Structure-activity relationship studies of allylamine type of antimycotics were carried out to evaluate the effect of naphthyl and methyl portion of naftifine. Compounds with 2,4-difluorophenyl( 2a-5a), 2,5-difluorophenyl(2b-5b), 4-ethylphenyl(2c-5c), 2-hydroxyphenyl(2d-5d) and 2-methylnaphthyl(2e-5e) instead of naphthyl group with hydrogen(3a-3e), methyl(4a-4e), and ethyl(5a-5e) in the place of methyl in naftifine were synthesized and tested their in vitro anti-fungal activity against five different fungi. Eight compounds( 3a, 4a, 5a, 3d, 4d, 4d, 5d, 3e, and 4e) showed significant anti-fungal activity against T. mentagroPhytes. (E)-N-(3-Phenyl-2-propenyl)-2- hydroxy-benzenemethaneamine( 3d) displayed moderate antifungal activity against all five different fungi.

Refinement of the Structure of p-Dimethylaminobenzaldehyde 4-(p-Ethoxyphenyl) Thiosemicarbazone (p-Dimethylaminobenzaldehyde 4-(p-Ethoxyphenyl) Thiosemicarbazone구조의 정밀화)

  • Seo, Il-Hwan;Seo, Chu-Myeong;Park, Yeong-Ja
    • Korean Journal of Crystallography
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    • v.2 no.1
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    • pp.12-16
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    • 1991
  • C18H22N4OS, Mr=342.47, monoclinic, P2₁/c,a=11.802(2), b=31.962(2), c=9.829(2)A, β=100.12(1)˚, V=3694.8A3,F(000)=1472, Z=8, Dx=1.246 Mg m-3, Dm=1.17Mg m-3,λ=0.71073 A, μ=0.15mm-1, T=294 K. final R=0.0856 for 3718 observed reflection (Fo>3σ(Fo)) There are two molecules in an asymmetric unit and a major difference between these molecules is in the C(9)-N(1)-C(6)-C(7) torsion angles [58.8(8)˚and 1(1)˚]. Both molecules have intramolecular N(1)-H(10)'N(3) hydrogen bonds [ 2.613(7) and 2.566(7) A] and assume V-shaped conformation with N(2) atoms at the verices. The two independent molecules are linked by the two N(2)-H(11)'S' hydrogen bonds[3.367(5) A and 3.421(4)A] and the dimergen are held together by van der Waals forces.

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Synthesis and Cationic Polymerization of Multifunctional Vinyl Ethers Containing Dipolar Electronic Systems

  • 이주연;김지향;김민정
    • Bulletin of the Korean Chemical Society
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    • v.20 no.3
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    • pp.307-313
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    • 1999
  • 2,4-Di-(2'-vinyloxyethoxy)benzylidenemalononitrile (la), methyl 2,4-di-(2'-vinyloxyethoxy)benzylidenecyanoacetate (lb), 3,4-di-(2'-vinyloxyethoxy)benzylidene malononitrile (2a), methyl 3,4-di-(2'-vinyloxyethoxy)benzylidenecyanoacetate (2b), 2,5-di-(2'-vinyloxyethoxy)benzylidenemalononitrile (3a), methyl 2,5-di-(2'-vinyloxyethoxy)benzylidenecyanoacetate (3b), 2,3-di-(2'-vinyloxyethoxy)benzylidenemalononitrile (4a), and methyl 2,3-di-(2'-vinyloxyethoxy)benzylidenecyanoacetate (4b) were prepared by the condensation of 2,4-di-(2'-vinyloxyethoxy)benzaldehyde, 3,4-di-(2'-vinyloxyethoxy)benzaldehyde, 2,5-di-(2'-vinyloxyethoxy) benzaldehyde, and 2,3-di-(2'-vinyloxyethoxy)benzaldehyde with malononitrile or methyl cyanoacetate, respectively. Trifunctional divinyl ether monomers 1-4 were polymerized readily with boron trifluoride etherate as a cationic initiator to give optically transparent swelling poly(vinyl ethers) 5-8 havina oxybenzylidenemalononitrile and oxycyanocinnamate, which is presumably effective chromophore for second-order nonlinear optical applications. Polymers 5-8 were not soluble in common organic solvents such as acetone and DMSO due to crosslinking. Polymers 5-8 showed a thermal stability up to 300 ℃ in TGA thermograms, which is acceptable for electrooptic device applications.

Synthesis and Biological Evaluation as a Potential Allylamine Type Antimycotics (알릴아민 항진균제의 합성과 생물학적 평가)

  • 정병호;조원제;천승훈;정순영;유진철
    • YAKHAK HOEJI
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    • v.47 no.5
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    • pp.293-299
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    • 2003
  • Structure-activity relationship studies of allylamine type of antimycotics were carried out to evaluate the effect of naphthyl and methyl portion of naftifine. Compounds with 4-fluorophenyl(2a-5a), 2-fluorophenyl(2b-5b), 2,4-dichlorophenyl(2c-5c), 2,6-dichlorophenyl(2d-5d), 4-nitrophenyl(2e-5e), and 2,3-dihydro-benzo[1,4]dioxan-6-yl( 2f-5f) instead of naphthyl group with hydrogen(3a-3f), methyl(4a-4f), and ethyl(5a-5f) in the place of methyl in naftifine were synthesized and tested their in vitro anti-fungal activity against five different fungi. Eight compounds(3a, 5a, 3c, 4c, 4d, 5d, 5e, and 4f) showed significant antifungal activity against T. mentagrophytes. (E)-N-Ethyl-(3-phenyl-2-propenyl)-4-nitro-benzenemethaneamine(5e) displayed moderate antifungal activity against all five different fungi.

Analysis of the Stoichiometry and the Domain for Interaction of Simian Virus 40 Small-t Antigen with Protein Phosphatase 2A

  • Yang, Sung-Il;Mumby, Marc C.
    • BMB Reports
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    • v.28 no.4
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    • pp.331-335
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    • 1995
  • Simian virus 40 (SV40) small-t antigen (small-t) has been known to regulate the activity of a cellular enzyme, protein phosphatase 2A (PP2A), composed of A. B, and C subunits, via binding to the A subunit In the study presented here, the stoichiometry of the binding of small-t to PP2A was determined to be 1: 1. It was also shown that small-t binds to the AC form of PP2A with a higher apparent affinity than it binds to the free A subunit. We also characterized the interaction of PP2A with wild-type and various mutant small-ts. A single-point mutant (Val134Met) and a double-point mutant (Trp147Gly;Leu152 Pro) of small-t exhibited 3-fold and 5-fold lower potencies in inhibiting PP2A activity. respectively. This suggests that the region around amino acids between 134 and 152 of small-t might be important in regulating the enzyme activity of PP2A.

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