New complexes,of bis(2,2'-diamino-4,4'-bithiazole)sulfate nickel(Ⅱ) and bis(2,2'-diami-no-4,4'-bithiazole)sulfate cobalt(Ⅱ),have been prepared.The complexes were characterized by infrared and UV-Vis spectroscopy,1H NMR,elemental analyses and molar conductivity.The effect of these complexes on the DNA synthesis of sarcoma 180 cells has been studied by the technique of isotopic liquid scintillation.The results indicated that complexes show ability to inhibit DNA synthesis of the tumor cells.In order to provide a molecular basis for understanding the biological effects,the probe,[trana-en2Os(η2-H2)](CF3SO3)2 (en,ethylenediamine) as a monitor was first used to explore interaction of the complexes with 2'-deoxyguanosine-5'-monophosphate (dGMP). 相似文献
Summary: Vinylphosphonic acid is polymerized at 80 °C by free radical polymerization to give a high‐molecular‐weight polymer ( of 6.2 × 104) as determined by static light scattering. High‐resolution NMR spectroscopy is used to gain microstructure information. Information based on tetrad probabilities is utilized to deduce an almost atactic configuration. In addition, 13C NMR spectroscopy gives evidence for the presence of head‐to‐head and tail‐to‐tail links. Refined analysis of the 1H NMR spectra allows for the quantitative determination of the fraction of these links (23.5% of all links). Experimental evidence suggests that the polymerization proceeds via cyclopolymerization of the vinylphosphonic acid anhydride as an intermediate. Titration curves indicate that high‐molecular‐weight poly(vinylphosphonic acid) PVPA behaves as a monoprotic acid.
Radical polymerization of vinylphosphonic acid proceeds by cyclopolymerization of its anhydride. 相似文献
Ni and/or Co molybdate based catalysts were synthetized by co-precipitation for the oxidative dehydrogenation of ethane reaction. The catalysts were characterized by several techniques such TGA-DTA, HT-XRD, XRD, LRS, N2 adsorption, XPS and TPR. The results showed that the addition of Ni or Co to MMoO4matrices (M=Ni or Co) led to a high dispersion of additives into the molybdenum matrix without the formation of a significant amount of other bulk metal oxides. Compared to the pure MMoO4, the modified molybdenum (Ni0.5Co0.5MoO4) presents a higher thermal stability (up to 1000 °C). It has a lower BET surface area and higher reduction temperature compared to those of the NiMoO4 sample. In the ODH of ethane, Ni0.5Co0.5MoO4 shows a lower catalytic activity compared to that of MMoO4 samples; however, the ethylene selectivity is enhanced (exceeding 90%). As a result, these series of catalysts show improved efficiency for ethylene production in the ethane ODH reaction. 相似文献
Two pyridinecarboxylato-bridged coordination polymers {[Co(pbc)2(H2O)] · H2O}n (1) and [Co(pbc)2]n (2) (Hpbc = 3-pyrid-3-ylbenzoic acid) have been synthesized by the hydrothermal method and characterized by X-ray single crystal diffraction. In 1, pbc? ligands link two Co(II) centers as μ2-N,O and μ2-N,O,O. Co(II) is six coordinate, octahedral. In 2, Co(II) is coordinated by four oxygens and two nitrogens. The ligands are μ2-N,O,O and μ3-N,O,O. Through different pbc? ligands, 2 generates a 3-D network composed of six-connected nodes. Compound 2 exhibits good photoluminescence, whereas 1 is nonemissive at room temperature. 相似文献
Two structurally related flexible imidazolyl ligands, bis(N-imidazolyl)methane (L1) and 1,4-bis(N-imidazolyl)butane (L2), were reacted with Cu(II), Co(II) and Ni(II) salts of aliphatic/aromatic dicarboxylic acids resulting in the formation of a number of novel metal–organic coordination architectures, [CuB2(ox)2(L1)2(H2O)2] · 4H2O (1) (ox = oxalate), [Cu(pdc)(L2)1.5] · 4H2O (2, pdc = pyridine-2,6-dicarboxylate), [Co(L)2(H2O)2](tp) · 4H2O (3, tp = terephthalate), [Ni(L1)2(H2O)2](ip) · 5H2O (4, ip = isophthalate), [Cu2(L1)4(H2O)4](tp)2 · 7H2O (5), [Co(mal)(L1)(H2O)] · 0.5MeOH (6, mal = malonate), [Co(pdc)(L1)(H2O)] (7). All the complexes have been structurally characterized by X-ray diffraction analysis. The different coordination modes of the dicarboxylate anions, due to their chain length, rigidity and diimidazolyl functionality, lead to a wide range of different coordination structures. The coordination polymers exhibit 1D single chain, ladder, 2D sheet and 2D network structures. The aliphatic and aromatic dicarboxylates can adopt chelating μ2 and chelating-bridging μ3 coordination modes, or act as uncoordinated counter anions. The central metal ions are coordinated in N2O4, N4O2, N2O3 and N3O3 fashions, depending on the ancillary ligands. The topology of 1 gives rise to macrocycles which are connected through hydrogen bonds to form 1D chains, whereas compound 2 exhibits a 1D polymeric ladder in which the carboxylate acts as a pincer ligand. Compounds 3–5 show doubly bridged 1D chains, and the dicarboxylate groups are not coordinated but form 2D corrugated sheets with water molecules intercalated between the cationic layers. Compound 6 has a 2D network sheet structure in which each metal ion links three neighboring Co atoms by the bis(N-imidazolyl)methane ligand. The cobalt compound 7, with a 2D polymeric double sheet structure, is built from pincer carboxylate (pdc) and 1,4-bis(N-imidazolyl)methane ligands. 相似文献
The mixed ligand complexes of Cu(II), Ni(II) and Co(II) with uridine and amino acids, L-alanine, L-phenylalanine and L-tryptophan
were synthesized and characterized by elemental analysis, conductivity data, infrared spectra, electronic spectra and magnetic
susceptibility data. In these complexes, the nucleoside (uridine) acts as a monodentate ligand coordinating through O(4) under
the conditions of investigation, whereas the amino acids coordinate through the carboxylate oxygen and the amino nitrogen.
Distorted octahedral geometry for Cu(II) and octahedral geometries for both Ni(II) and Co(II) are proposed. 相似文献
Oils and fats derived from animals and plants provide a good renewable source for polymer precursors. In this investigation, fatty acids derived from plant oils and diols were used as monomers to produce polyesters by melt polycondensation. Sebacic acid, hexanediol, and hydroquinone were used as precursors in the polymer synthesis. The polymers were characterized by gel permeation chromatography, Fourier transform infrared spectroscopy, three-bending point flexural test, X-ray diffraction, tensile testing, and contact angle. The resulting polyesters were blended with epoxies to create materials with an increased elongation at break without affecting other mechanical properties. 相似文献
