• BMB Reports
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• 제35권4호
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• pp.389-394
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• 2002

$[Ru(bpy)_2(dppz)]^2+$ (bpy=2,2'-bipyfidine, dppz=dipyrido[3,2-a:2',3'-c]phenazine) (RuBD), a long-lifetime metal-ligand complex, displays favorable photophysical properties. These include long lifetime, polarized emission, but no significant fluorescence from the complex that is not bound to DNA. To show the usefulness of this luminophore (RuBD) for probing the bending and torsional dynamics of nucleic acids, its intensity and anisotropy decays when intercalated into supercoiled and relaxed pTZ18U plasmids were examined using frequency-domain fluorometry with a blue light-emitting diode (LED) as the modulated light source. The mean lifetimes for the supercoiled plasmids (< $\tau$ >=148 ns) were somewhat shorter than those for the relaxed plasmids (< $\tau$ >=160 ns). This suggests that the relaxed plasmids were shielded more efficiently from water. The anisotropy decay data also showed somewhat shorter slow rotational correlation times for supercoiled plasmids (288 ns) than for the relaxed plasmids (355 ns). The presence of two rotational correlation times suggests that RuBD reveals both the bending and torsional motions of the plasmids. These results indicate that RuBD can be useful for studying both the bending and torsional dynamics of mucleic acids.

• 한국환경과학회지
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• 제6권5호
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• pp.505-512
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• 1997

The Interfacial characteristics between various heavy metals and hydrous FeS were investigated. Heavy metals which have lower sulfide solubilities than FeS undergoes the lecttice exchange reaction when these metal tons contact FeS In the aqueous phase. For heavy metals which have higher suede solubilities than FeS, these metal ions adsorb on the surface of FeS. Such characteristic reactions were interpreted by the soled solution formation theory. The presence of ligand such as EDTA reduced largely metal removal efficiency due to formation of metal-ligand complex In the solution. In an attempt to elucidate the Interfacial characteristics, zeta potential of the hydrous FeS In the absence and In the presence of various metal loons were measured and analyzed.

• Journal of Photoscience
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• 제11권1호
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• pp.35-40
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• 2004

[Ru(2,2'-bipyridine)$_2$(4,4'-dicarboxy-2,2'-bipyridine)]$^{2+}$(RuBDc) is a very photostable probe that possesses favorable photophysical properties including long lifetime, high quantum yield, large Stokes' shift, and highly polarized emission. To evaluate the usefulness of this luminophore (RuBDc) for studying macromolecular dynamics, its intensity and anisotropy decays when conjugated to RNA bacteriophage MS2 were examined using frequency-domain fluorometry with a high-intensity, blue light-emitting diode (LED) as the modulated light source. The intensity decays were best fit by a sum of two exponentials, and the mean intensity decay time was 442.2 ns. The anisotropy decay data showed a single rotational correlation time (2334.9 ns), which is typical for a spherical molecule. The use of RuBDc enabled us to measure the rotational correlation time up to several microseconds. These results indicate that RuBDc can be useful for studying rotational diffusion of biological macromolecules.s.

• 약학회지
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• 제47권6호
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• pp.356-360
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• 2003

Nitroso-2-naphthol-3,6-disulfonic acid, disodium salt (NRS) was used as an organic ligand to prepare basic drug-selective polymeric membrane electrode. The sensing membrane of the electrode consited of basic drug-meta1(II)-NRS as an ion-exchanger site in a poly(vinyl chloride) matrix plasticized with 2-nitrophenyl octyl ether (NPOE). The metal ions used were Fe$^{2+}$, Co$^{2+}$, Ni$^{2+}$ and Cu$^{2+}$. The electrodes exhibited fast and wide linear response in the basic drug concentration of 10$^{-5}$ ∼10$^{-3}$ mol/l with a response slope of 50∼60 mV/decade in a buffer solution of pH 4∼8. The electrodes exhibited good selectivity for many basic compounds.mpounds.

• Bulletin of the Korean Chemical Society
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• 제19권4호
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• pp.457-462
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• 1998

A chiral pentadentate bis-amide ligand, 1,9-bis(S)-pyrrolidinyl-2,5,8-triazanonane-1,9-dio ne$(S,S-prodienH_2)$ has been synthesized from the reaction of bis(2-aminoethyl)amine(dien) and S-proline, and the structure of $[Co(S,S-prodien)H_2O]ClO_4$ has be en determined by single crystal X-ray diffraction. The geometrical structure of the Co(III) complex has been an αβ -form, where the dien moiety of ligand chelates to a facial in metal center, and the aqua ligand coordinates a cis site to the secondary nitrogen of dien. The Co-N(1), Co-N(3) distances of two amide moiety in S,S-prodien are shorter than the other Co-N(2), Co-N(4), and Co-N(5) distances because of the increased basicity of nitrogen in amide. The complex crystallizes in the monoclinic space group $P2_1$(#4), with a=7.838(1), b=12.675(1), c=9.710(1) Å, β=100.39(1) and z=2. Refinement gives the final R and $R_w$ values of 0.045 and 0.057, respectively for 2130 observed reflections. Based upon the CD and X-ray data, it is identified that the absolute configuration of the αβ -$[Co(S,S-prodien)H_2O]ClO_4$ has a Λ-form.

• 대한화학회지
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• 제54권1호
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• pp.43-48
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• 2010

p-페닐렌 디아민과 maleic anhydride, 아세틸 아세톤과 커플된 O-아미노 페놀의 아조화합물으로 부터 폴리이미드가 만들어졌다. 합성된 폴리이미드(PA)는 DMF용매 속에 다른 몰비율로 녹아있는 $Co^{+2},\;Cr^{+2},\;Ni^{+2},\;Cu^{+2},\;Zn^{+2},\;Cd^{+2}$ and $Fe^{+3}$ 를 포함하는 전이금속이온들의 금속염들과 함께 환류되었다. 이 complex들은 원소분석과 열분석, IR, $^1H$ NMR으로 구조분석, 특성 연구되었다.

• Bulletin of the Korean Chemical Society
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• 제26권6호
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• pp.925-929
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• 2005

Some new metal(II) complexes, $M^{II}L_2$ [M = Mn (1), Co (2), Ni (3), Cu (4), and Zn (5)] of 2-acetylpyridine benzoylhydrazone ligand (HL) containing trifunctional NNO-donor system have been synthesized and crystallographically characterized for the complex 1 and 5. The complexes consist of two ligands to give sixcoordinate, which are bonded to the metal atom on a meridional plane through acetylpyridine ring nitrogen, azomethine nitrogen, and benzoyl oxygen atoms, respectively. The coordination geometry for other complexes was identified on the basis of the physicochemical data by elemental analyses, FAB -MS, IR, $^1H$ NMR, and electronic spectral measurements. The resulting data indicated that the complexes are accordance with the above formulation.

• Journal of Photoscience
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• 제7권4호
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• pp.155-159
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• 2000

[Ru(bpy)$_2$(dppz)]$^2$$^{+}$ (bpy = 2,2'-bipyridine, dppz = dipyrido[3,2-a:2',3'-c]phenazine)(RuBD), a long-lifetime metal-ligand complex displays photophysical properties including long lifetime, polarized emission, and very little background fluorescence. To further show the usefulness of this luminophore(RuBD) for probing nucleic acid dynamics, its intensity and anisotropy decays when bound to tRN $A^{val}$ were examined using frequency-domain fluorometry with a blue light-emitting diode(LED)as the modulated light source. Unexpectedly much longer mean lifetime was obtained at 4$^{\circ}C$(<$\tau$>=178.3 ns) as compared to at $25^{\circ}C$(<$\tau$>=117.0 ns), suggesting more favorable conformation of tRN $A^{val}$ for RuBD when intercalated at 4$^{\circ}C$. The anisotropy decay data showed longer rotational correlation times at 4$^{\circ}C$(52.7 and 13.0 ns) than at $25^{\circ}C$ (32.9 and 10.3 ns). The presence of two rotational correlation times suggests that RuBD reveals both local and overall rotational motion of tRN $A^{val}$. Due to long lifetime of RuBD and small size of tRN $A^{val}$, very low steady-state anisotropy values were observed, 0.048 and 0.036 at 4 and $25^{\circ}C$, respectively. However, a clear difference in the modulated anisotropy values was seen between 4 and $25^{\circ}C$. These results indicate that RuBD can be useful for studying hydrodynamics of small nucleic acids such as tRN $A^{val}$.^{val}$.>.$.>.

• 대한화학회지
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• 제54권5호
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• pp.515-522
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• 2010

o-phenylene diamines, dehydroacetic acid (DHA) 및 p-chloro benzaldehyde에서 유도된 세자리 Schiff 염기 리간드인 4-hydroxy-3(1-{2-(benzylideneamino)-phenylimino}-ethyl)-6-methyl-2H-pyran-2-one (HL)의 Cu(II), Ni(II), Co(II), Mn(II) 및 Fe(III) 착물의 형성상수와 항미생물 활성과의 관계를 연구하였다.리간드와 착물은 원소분석, 전도도, 자기수자율, 열분석, X-선 회절, IR, $^1H$-NMR, UV-vis 및 질량 스펙트럼으로 특성조사를 하였다. 분석데이터로부터 착물들의 화학량론비가 1:2 (금속:리간드)임을 알았다. 금속 착물들의 몰 전도도 값은 이들의 비전해질 성질을 의미한다. X-선 회절 데이터에서 Ni(II) 착물은 단사정계 그리고 Cu(II) 및 Co(II) 착물은 삼사정계 결정계임을 규명하였다. IR 스펙트럼 데이터로부터 리간드는 중심금속에 대해 ONN 주개원자 배열의 세자리 리간드로 행동함을 알았다. 열적 행동 (TG/DTA)과 Coats-Redfern 법에 의해 계산한 반응속도 파라메터는 착물형성 과정에서 좀 더 질서 있는 활성화 상태를 제안하고 있다. 착물의 양성자화 상수를 THF:물 (60:40) 용액, $25^{\circ}C$ 및 이온세기 ${\mu}=0.1\;M$ ($NaClO_4$)에서 전위차법으로 측정하였다. Staphylococcus aureu 및 Escherichia coli.에 대한 항박테리아 활성을 시험관에서 조사하였다. 또한 Aspergillus Niger 및 Trichoderma에 대한 항세균 활성도 조사하였다. 금속 이온 및 착물의 안정도가 항미생물학적 활성에 미치는 영향을 고찰하였다.

• 대한화학회지
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• 제59권3호
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• pp.215-224
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• 2015

Unsymmetrical tetradentate Schiff base N-(2-hydroxy-5-methylacetophenone)-N'-(2-hydroxy acetophenone) ethylene diamine (H₂L) and its complexes with Cr(III), Mn(II), Fe(III), Co(II), Ni(II) and Cu(II) have been synthesized and characterized by elemental analyses, magnetic susceptibility measurements, IR, electronic spectra and thermogravimetric analyses. ¹H, ¹³C-NMR and FAB Mass spectra of ligand clearly indicate the presence of OH and azomethine groups. Elemental analyses of the complexes indicate that the metal to ligand ratio is 1:1 in all complexes. Infrared spectra of complexes indicate a dibasic quadridentate nature of the ligand and its coordination to metal ions through phenolic oxygen and azomethine nitrogen atoms. The thermal behavior of these complexes showed the loss of lattice water in the first step followed by decomposition of the ligand in subsequent steps. The thermal data have also been analyzed for the kinetic parameters by using Horowitz-Metzger method. The dependence of the electrical conductivity on the temperature has been studied over the temperature range 313-403 K and the complexes are found to show semiconducting behavior. XRD and SEM images of some representative complexes have been recorded. The antimicrobial activity of the ligand and its complexes has been screened against various microorganisms and all of them were found to be active against the test organisms. The Fe(III) and Ni(II) complex have been tested for the catalytic oxidation of styrene.