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151.
Intramolecular stacking interaction in mixed-ligand complexes containing ATP4- and aromatic N-heterocyclic ligands 总被引:1,自引:0,他引:1
The stability constants of the binary ML2+ and ternary M(ATP)L2- complexes,where L=Iq (isoquinoline) or BIm (benzimidazole) and M=Zn2+ or Cd2+,have been determined by poten-tiometric pH titration in aqueous solution at I=0.1 mol/L (NaClO4),T=25℃.The stability of the ternary complexes characterized by corresponding to the equilibrium M(ATP)2-+ML2+=M(ATP)L2-+M2+ is higher than what would be expected on statistical grounds.The increase may be related to the stacking interaction between the aromatic ring of the ligands L and the purine moiety of ATP4- 1H NMR studies of Zn2+/ATP4-/L confirm the presence of stacking in the ternary complexes.It is concluded that the strength of the intramolecular stacking interaction is dependent on the structure of the aromatic ring of the ligand L and the formation of a metal ion bridge.Possible implications are discussed briefly. 相似文献
152.
The Interaction of three complexes [Cu(phen)(Gly)(H2O)]·ClO4·2.5H2O (1), [Cu(phen)(L-Val)(H2O)]·ClO4 (2) and [Cu(phen)(L-Ile)(H2O)]·ClO4 (3) (phen=1,10-phenanthroline, Gly=glycinate, L-Val=L-valinate, L-Ile=L-isoleucinate) with DNA have been investigated by electronic absorption spectroscopy, ethidium bromide(EB) fluorescence spectroscopy, viscosity and gel electrophoresis measurements. The intensity of maximal absorption peaks from absorption spectra are weakened with dropping DNA into the complexes. The emission intensity of EB-DNA systems in fluorescence spectroscopy have descended 50%, when the data of CCu / CDNA is 30~40. Moreover, the viscosity of DNA increase and then decrease with the increasing of complexes. All of the results indicate that the interaction of complexes with DNA are partial intercalation, and the result of agarose gel electrophoresis show that the complexes can cleave pBR322 DNA in the present of H2O2 / vitamin C. 相似文献
153.
Ternary complex [Cu(L-Ile)(TATP)(H2O)](ClO4)] was synthesized and characterized by molar conductivity, rotational analysis, spectroscopic (IR and UV-Vis) and X-ray diffraction methods, where L-Ile=L-Isoleucine, and TATP=1,4,8,9-tetraazatriphenylene. The complex crystallizes in triclinic space group P1 with two molecules in a unit cell of dimensions a=8.240 3(9) nm, b=11.914 9(13) nm, c=13.436 0(15) nm, α=109.136(2)°, β=101.101(2)°, γ=106.302(2)°. V=1.209 2(5) nm3, Z=2, Dc=1.589 Mg·m-3, μ=1.132 mm-1,R1=0.036 9, wR2=0.098 0. The crystal contains two independent [Cu(L-Ile)(TATP)(H2O)]+ complexes for Cu1 and Cu2, respectively, having essentially the same distorted square-pyramidal structure, where each Cu(Ⅱ) ion is coordinated with two nitrogen atoms of TATP and the amino nitrogen atom and one carboxylate oxygen atom of L-Ile in the equatorial positions and one water oxygen atom at an axial position. Furthermore, the primary studies on the interaction between the complex and calf thymus DNA were also performed by electronic absorption spectroscopy and viscosity methods. CCDC: 244231. 相似文献
154.
陶瓷电容器化学镀铜的研究 总被引:1,自引:0,他引:1
陶瓷电容器化学镀铜的研究袁永明万家义王惠萍(四川大学化学系成都610064)关键词陶瓷电容器以铜代银化学镀中图分类号O69陶瓷电容器是最基本的电子元件,目前国内外大都采用涂银(印银)-烧银法制作银电极。这种方法需要消耗大量的贵金属银,设备投资贵、成本... 相似文献
155.
用PH电位滴定法测定 篱子(M^2+=Cu^2+,Co^2+,Ni^2=,Zn^2+,Cd^2+)与核酸碱基(P=腺嘌呤,胞嘧啶)形成的二夫配合物以及与腺甘-5'-三酸(ATP)形成的三元混配配合物的稳定常数,三元配合物相对于二元酚物的稳定性用平衡常数ΔlgKM大,这可能与三元混配配合物分子内存在配体间的芳环堆积、氢键作用以及πA-πB协同效应有关。 相似文献
156.
157.
ReCI(CO)5 catalyzed the dehydration reaction of aromatic compounds with 1,3,5-trioxane or aqueous formaldehyde (37 wt%) under air. The reactions of a variety of aromatic compounds beating electron-donating group(s) with 1,3,5-trioxane afforded the corresponding diarylmethanes in moderate to good yields. 相似文献
158.
159.
Experimental Study of Single and Double Electron Detachment Cross Sections for Cl^- in Collision with He 下载免费PDF全文
Single-electron detachment (SED) and double-electron detachment (DED) for chlorine negative ions in collision with helium are investigated in the energy region of 5-30 keV (SED) and 5-19 ke V (DED) by growth rate method, respectively. Experimental data from this work are compared with the previous reported data, and a general discussion is given. 相似文献
160.
In this paper, we present a basic theory of mean-square almost periodicity, apply the theory in random differential equation, and obtain mean-square almost periodic solution of some types stochastic differential equation. 相似文献