• YAKHAK HOEJI
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• v.15 no.2
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• pp.41-52
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• 1971

Cu(II) chelates of several sulfanilamide derivatives (Sulfa-Cu) were prepared and their effects on solubility, absorptivity in intestinal lumen, biding tendency with serum protein and erythrocytes, concentration in rabbit blood, and acetylation rate were studied in comparison with their free ligand forms. For solubility concerned, the partition coefficients of Sulfa-Cu are decreased as following order: Sulfadimethoxine Copper chelate (SDM-Cu), Sulfamethoxypyridazine Copper chelate (SD-Cu), Sulfamerazine Copper chelate (SM-Cu), Sulfaisoxazole Copper chelate (SIX-Cu). The partition coefficients of SDM-Cu and ST-Cu were much greater than those of ligands. this phenomenone acounts for the rapid absorption of SDM-Cu and ST-Cu in the rat small intestine (in situ). The Sulfa-Cu were absorbed at the intestinal lumen of a rat in the rate of first order and there was no difference between long acting sulfa drugs and their Cu0chelates in biological half lives. In binding experiments, sulfa-Cu binded with serum protein in lower ratio than their ligands except SIX-Cu. On other hand, acetylation rates of sulfa-Cu were higher than those of free sulfa drugs and the acetylation rate were higher than those of free sulfa drugs and powder. In a experiment on Sulfa-Cu concentration in rabbit blood, the half lives of SD-Cu, SIX-cu, ST-Cu, and SM-Cu were longer than those of their ligands. Above all, the half life of SD-Cu appeared to be approximately 3.5 times logner than that of corresponding ligand, SD. When absorption of sulfa drugs or sulfa-Cu at the small intestinal lumen of a rat and the concentration in rabbit blood after absorption were compared, it was found that there was not always conrrelated.

• Journal of the Korean Chemical Society
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• v.36 no.5
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• pp.697-708
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• 1992

Liquid Chromatographic behavior of Ni(II) in Isonitrosoethylacetoacetate Imine(IEAA-NR), Ni(IEAA-NH)(IEAA-NR)(R = H, CH_3, C-2H_5, n-C_4H_9, C_6H_5-CH_2) chelates were investigated by reversed-phase HPLC on Micropak MCH-5 column using methanol/water as mobile phase. The optimum conditions for the separation of Ni(IEAA-NH)(IEAA-NR) chelates were examined with respect to the effect of the flow rate, sample solvent, mobile phase strength and column temperature. It was fo$und that metal chelates were properly eluted in an acceptable range of capacity factor value(0{\le}logk'{\le}1). The dependence of the logarithm of capacity factor (k') on the volume fraction of water in the binary mobile phase as well as on the liquid-liquid extraction distribution ratio (Dc) in methanol-water/n-alkane extraction system showed the good linearties, and the dependence of the logarithm of capacity factor (k') on the column temperature and on the enthalpy exhibited the good linearties, and the compensation temperature ({\beta}) from the slope was 773.47{\circ}K. It was suggested that the retention of metal chelates was largely affected by the hydrophobic effect.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.19 no.1
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• pp.20-30
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• 1993

Liquid Chromatographic behavior of Pd(II) in Isonitosoethylacetoacetate imine IEAA-NR: R=H, CH3, C2H5, n-C3H7, n-C4H9, C6H5-CH2) Chelates were investigated by reversed phase high performance 1iquid chromatography on Micropak MCH-5 Column using Methanol /water as mobile phase. The optimum condition for the separation of Pd-Isonitrosoethylacetoacetate imine chelates were examined with respect to the flow rate, mobile phase strength. It was found that Pd(IEAA-NR)2 chelates were eluted in an acceptable range of the capacity factor value (0 $\leq$ log k' $\leq$ 1), The dependence of the logarithm of capacity factor(k') on the volume fraction of water in mixture with in the binary mobile phase was examined. Also, the dependence of k'on the liquid-liquid extraction distribution constant in methanol-water / n-alkane extraction system was on system was invert tigated for Pd(IEAA-NR)2. Both kinds of dependence are linear, which suggests that the retention of the electroneutral metal chelates be largely due to the solvophobic effect.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.372-373
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• 2009

In this work, the effects of substrate on the formation of YBaCuO by CVD were investigated by observing the microstructure and the crystallographic orientation and by measuring the temperature dependence of electrical resistance. Source materials used to synthesize the YBaCuO superconducting film were beta-diketone chelates of Y, Ba and Cu. These chelates were evaporated at $137-264^{\circ}C$. The source vapors of Y, Ba and Cu were transported into hot zone by using Ar gas and $O_2$ gas was introduced separately.

• Journal of the Korean Chemical Society
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• v.12 no.3
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• pp.81-84
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• 1968

Stabilities of chelates of 7-nitroso-8-hydroxyquinoline-5-sulfonate have been determined for divalent transition metal ions, Mn(Ⅱ), Fe(Ⅱ), Co(Ⅱ), Ni(Ⅱ), Cu(Ⅱ), and Zn(Ⅱ) by means of the Calvin-Bjerrum technique. Comparison of these stability constants with those obtained for 8-hydroxyquinoline, and 8-hydroxyquinoline-5-sulfonate shows that the observed differences are essentially the results of the lower basicity of the sulfonated group and different metal-ligand bond. The divalent metal chelate stability sequence is not in agreement with the reported metal orders for other chelating agents. The stabilities were found to follow the order Mn(Ⅱ) < Fe(Ⅱ) ${\approx}$ Co(Ⅱ) > Ni(Ⅱ) < Cu(Ⅱ) > Zn(Ⅱ).

• Journal of the Korean Chemical Society
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• v.55 no.6
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• pp.912-918
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• 2011

Tetraaza Schiff base macrocyclic ligands, $L^1$,$L^2$ and their transition metal chelates have been synthesized and characterized by elemental analyses, IR, electronic, EPR and $^1H$ NMR spectra, TGA and magnetic measurements. The molar conductance of one milli-molar solution of the complexes measured in DMF indicates that the divalent metal complexes are nonelectrolyte while those of trivalent metal ion, are 1:1 electrolytic in the same solvent. The reduction of Racah parameter from the free ion value confirms the presence of considerable covalence of metal ligand sigma bond in the Co(II) and Mn(II) complexes. The EPR spectra of Cu(II) complexes at room temperature shows axial symmetry indicating a $d_x{^2}_{-y}{^2}$ ground state with significant covalent character. The thermal analysis suggests that the complexes do not contain water molecules because only the metal is left as residue.

• Journal of Applied Biological Chemistry
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• v.49 no.1
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• pp.8-10
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• 2006

Compositions of methionine-metal chelates have been investigated by FT-IR and XRD studies to elucidate their molecular structures. It was concluded that Copamin and Zincamin contain a high percentage of crystalline products, presumably 2:1 Methionine-Cu or Zn complexes. On the contrary, FT-IR and XRD spectra of Ferramin didn't show any characteristics of the chelate and it was concluded to contain major components of starting $FeSO_4$ and methionine without chelation.

• Bulletin of the Korean Chemical Society
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• v.28 no.5
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• pp.863-866
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• 2007

• Bulletin of the Korean Chemical Society
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• v.18 no.1
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• pp.113-116
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• 1997

• Bulletin of the Korean Chemical Society
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• v.17 no.12
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• pp.1158-1161
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• 1996