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91.
《Journal of Coordination Chemistry》2012,65(6):934-944
The reaction of pyridine-2,6-dicarbaldehyde or 2,6-diacetylpyridine with 1,2-bis(o-aminophenylthio)ethane (1) in acetonitrile in the presence of stoichiometric amounts of iron(II) perchlorate gave the complexes [(pyN3S2)FeII(ClO4)2] (4) and [(pyN3Me2S2)FeII(ClO4)2] (5) of the 15-membered N3S2 macrocyclic ligands, pyN3S2 ?=?{6,7-dihydro-15,19-nitrilobenzo(e,p)(1,4,7,15)dithiadiazacyclo-heptadecine-N,N′,N″,S,S′} and pyN3Me2S2?=?{6,7-dihydro-16,18-dimethyl-15,19-nitrilobenzo(e,p)(1,4,7,15)dithiadiazacyclo-heptadecine-N,N′,N″,S,S′}, respectively. Physical measurements led to the conclusion that these complexes contained seven-coordinate iron(II) and a single-crystal X-ray examination of 4 confirmed this. Coordination of the Fe(II) center in 4 is best described as distorted pentagonal-bipyramidal with the three nitrogen atoms and two sulfur donors of the macrocycle defining the pentagonal plane and the perchlorate ions occupying axial positions. Room temperature (293?K) magnetic moments of 4 and 5 (μ eff?=?4.9 and 4.7 B.M., respectively) are close to the value predicted for high-spin d6 systems. 相似文献
92.
以1-氨乙基哌嗪和丙烯腈为原料合成了新型有机多胺1-(N,N-二氨基丙基)氨基乙基-4-氨基丙基哌嗪,并以此为配体,与高氯酸钴进行配位反应,得到其配合物[Co(L)HCl](ClO4)2的晶体。通过元素分析、测摩尔电导率和X射线衍射对所得晶体进行了分析。结果显示,该晶体结构属于四方晶系,空间群I4/m,a = 2.5006(3),b = 2.5006(3) c = 0.85615(11) nm, Mr =594.79,V = 5.3534(10) nm3,Z=8, F(000)= 2488, Dc = 1.476g/cm3,μ(MoKα)= 0.989mm-1,最终偏离因子R1 = 0.0666, wR2 = 0.1852 ( I > 2σ( I) )。采用琼脂扩散法测定目标产物的抑菌性能。结果表明, [Co(L)HCl](ClO4)2对金黄色葡萄球菌、大肠杆菌、枯草芽孢杆菌、鳗弧菌均有一定的抑制作用。 相似文献
93.
O. Pietraszkiewicz M. Pietraszkiewicz H. Radecka J. Radecki 《Journal of inclusion phenomena and macrocyclic chemistry》2001,41(1-4):129-134
Lipophilic polyamines 1 and 2 form stable monolayers at the air–water interface. The shapes of the isotherms show a strong pH-dependence due to different stages of polyamine protonation. For all isomers of dihydroxybenzene the strong interaction with 1 and 2 can be observed at pH 4, 6, and 8. Polyamines 1and 2 in the PVC liquid membrane act as the sensory element of the potentiometric sensor for selective determination of catechol in the presence of other isomers of dihydroxybenzenes. 相似文献
94.
大环多胺配体BDBPH的设计合成及其晶体结构 总被引:2,自引:0,他引:2
用Pb(SN)2作模板,2,6-二甲酰基对甲苯酚与二亚乙基三胺通过[2+2]缩合反应,经NaBH4还原、脱Pb2+、酸化等操作,得晶体BDBPH·6HBr·4H2O.晶体属单斜晶系,P21/c空间群,晶体学参数:a=1.4441(5)nm,b=1.1482(4)nm,c=1.2090(6)nm,α=90°,β=96.92°,γ=90°,V=1.9900nm3大环分子采取椅式构型,6个Br-和4个H2O分子对称分布于大环两侧.该大环配体结构新颖,可用于多种金属配合物的研究,对进一步了解金属酶活性中心的结构及其催化作用机理具有重要价值. 相似文献
95.
Naturalmacrocycliclactonesandlactamsastheionophoreshaveabsorbedextensiveinterestsbecauseoftheirveryhighselectiverecognitionforalkalimetals.rorexample,nactinslandvalinomycin'havethehighestselectivityforpotassiumamongalltheionopohores.Artificialmacrocycliclactonesalsoshowedselectivityforcanons,althoughthebindingstrengthwaslowerthanthatofcommoncrownethers3.Calixareneswereaveryimportantkindofartificialreceptors,whosederivativeshaveshowedthehighestselectivityforNa ,K andCs amongthesynthesizedmacro… 相似文献
96.
大环手性磷酰胺对氨基酸衍生物的分子识别研究 总被引:2,自引:0,他引:2
以(S)-α-甲基苯乙胺和天然氨基酸(L-丙氨酸、L-苯甘氨酸及L-苯丙氨酸)为手性源,以2,5-二(邻羟基苯基)-1,3,4- 二唑和2,4-二(邻羟基苯基)-1,3,5- 二唑为刚性单元,合成了一系列具有光学活性的新型含 二唑磷酰胺和磷酯手性大环化合物.用NMR,IR和FABMS方法研究了所合成的手性大环对氨基酸甲酯盐酸盐和二肽的分子间相互作用和分子识别.结果表明,这些主体对D-或L-氨基酸甲酯盐酸盐和二肽具有选择性的结合作用. 相似文献
97.
Summary: Poly(arylene ether amine)s were synthesized by a nucleophilic aromatic substitution polycondensation of bis[4‐fluoro‐3‐(trifluoromethyl)phenyl]amine with several bisphenols. Even though the monomer has an electron‐donating diphenylamine moiety, which normally deactivates a nucleophilic aromatic substitution (SNAr) reaction, the polymerization proceeded by a SNAr reaction to give high‐molecular‐weight polymers. The polymers show good solubility in common organic solvents and have Tgs in the range of 123 °C to 177 °C.
98.
Lämmerhofer M 《Journal of chromatography. A》2005,1068(1):31-57
A review on the advantages, peculiarities, and the potential of enantioselective capillary electrochromatography (CEC) in nonaqueous media is presented. Some fundamentals on CEC with particular focus on enantioselective CEC are discussed. The strategies, concepts, preferentially utilized chiral selectors and column technologies that have been utilized to succeed in highly efficient enantiomer separations by nonaqueous CEC are described thoroughly. 相似文献
99.
Three novel Zn(II) complexes,[Zn4L1Cl4]-3H2O(1),[Zn4L2Cl4]-2DMF(2) and[Zn4L3Cl4]H2O(3),have been synthesized and structurally characterized.In these complexes,interesting 32-membered dodecadentate macrocyclic ligands were generated in situ by ’2 + 2’ type condensation reactions between a tetraamine and various dialdehydes.All the complexes are isostructurally tetranuclear Zn(Ⅱ) complexes,containing endogenous alkoxo and phenoxo bridges.Applications of the macrocyclic ligands as Zn2+ sensors have been investigated.Take H4L1 for example,it exhibits a 4-fold fluorescence enhancement upon the addition of 2 equiv.of Zn2+ in MeOH. 相似文献
100.
《Journal of Saudi Chemical Society》2014,18(1):53-58
Complexes of Mn(II), Co(II), Ni(II), Pd(II) and Pt(II) were synthesized with the macrocyclic ligand, i.e., 2,3,9,10-tetraketo-1,4,8,11-tetraazacycoletradecane. The ligand was prepared by the [2 + 2] condensation of diethyloxalate and 1,3-diamino propane and characterized by elemental analysis, mass, IR and 1H NMR spectral studies. All the complexes were characterized by elemental analysis, molar conductance, magnetic susceptibility measurements, IR, electronic and electron paramagnetic resonance spectral studies. The molar conductance measurements of Mn(II), Co(II) and Ni(II) complexes in DMF correspond to non electrolyte nature, whereas Pd(II) and Pt(II) complexes are 1:2 electrolyte. On the basis of spectral studies an octahedral geometry has been assigned for Mn(II), Co(II) and Ni(II) complexes, whereas square planar geometry assigned for Pd(II) and Pt(II). In vitro the ligand and its metal complexes were evaluated against plant pathogenic fungi (Fusarium odum, Aspergillus niger and Rhizoctonia bataticola) and some compounds found to be more active as commercially available fungicide like Chlorothalonil. 相似文献