The syntheses,crystal structure,thermal analysis,and anticancer activities of novel dipicolinate complexes

[Cu(pydc)(eim)₃]?H₂O (1), [Cu(pydc)(4hp)(H₂O)] (2), and [Ni(pydc)(3hp)(H₂O)₂][Cu(pydc)(3hp)(H₂O)₂]?3H₂O (3) (H₂pydc = 2,6-pyridinedicarboxylic acid or dipicolinic acid, eim = 2-ethylimidazole, 4hp = 4-hydroxypyridine, 3hp = 3-hydroxypyridine) were synthesized and characterized by elemental analysis, spectroscopic measurements (UV–vis and IR spectra), and single-crystal X-ray diffraction. Crystal analysis revealed that the complexes extended to 3-D supramolecular networks through intermolecular H-bonding and molecular interactions between the ligand moieties and water molecules. The thermal stabilities of complexes are investigated by thermogravimetry, differential thermogravimetry, and differential thermal analysis techniques. The effects of complexes on the proliferation of HT-1080 fibrosarcoma cells were investigated using the quick cell proliferation assay. The cell viability changes were found to depend on the concentrations and type of complex.     

Synthesis,crystal structure,antibacterial activities,and DNA-binding studies of a new μ-oxamido-bridged binuclear copper(II) complex

A new μ-oxamido-bridged dicopper(II) complex, Cu₂(heap)(NO₃)₂ (1), where heap is the dianion of N,N′-bis(N-hydroxyethylaminopropyl)oxamide, has been synthesized and characterized by elemental analysis, molar conductivity, IR and electronic spectral studies, and X-ray single-crystal diffraction. The complex consists of a neutral centro-symmetric binuclear copper(II) unit with an inversion center at the midpoint of the Cl?Clⁱ bond. The copper(II) has square-pyramidal coordination geometry and the bridging heap adopts a bis-tetradentate conformation. The binuclear units are linked into a 3-D framework by N?H ··· O, O?H ··· O, and C?H ··· O hydrogen bonds. Due to weak coordination between copper(II) and nitrate, the neutral dicopper(II) units are present as binuclear cations and nitrate anions in solution. Antibacterial assays indicate that the complex shows better activity than the ligand. Interactions of the complex with herring sperm DNA (HS-DNA) have been investigated by using cyclic voltammetry, UV absorption titrations, ethidium bromide fluorescence displacement experiments, and viscometry measurements. The results suggest that the binuclear copper(II) complex interacts with HS-DNA by electrostatic interaction with intrinsic binding constant of 3.33 × 10⁴ M^?1.     

Synthesis of new unsymmetrical “end-off” phenoxo bridged copper(II), nickel(II) and zinc(II) complexes: spectral,magnetic, electrochemical,catalytic, and antimicrobial studies

A new class of unsymmetrical end-off, aminomethylated N-methylpiperazine and aminomethylated diethanolamine binucleating ligands, 2-[bis(2-hydroxyethyl)aminomethyl]-6-[(4-methylpiperazin-1-yl)methyl]-4-methylphenol (HL¹) and 2-[bis(2-hydroxyethyl)aminomethyl]-6-[(4-methylpiperazin-1-yl)methyl]-4-acetylphenol (HL²) were synthesized by following sequential aromatic Mannich reactions. Their mononuclear and binuclear Cu(II), Ni(II) and Zn(II) complexes have been synthesized and their formulation was confirmed by analytical and spectral analysis. The mononuclear Cu(II) complexes have a magnetic moment value close to the spin only value with four hyperfine EPR signals. The binuclear Cu(II) complexes have an antiferromagnetic interaction with a broad EPR signal. Electrochemical studies of the complexes reveal that all the redox processes are irreversible. Catecholase activity of Cu(II) complexes and the hydrolysis of 4-nitrophenylphosphate using Cu(II), Ni(II), and Zn(II) complexes were carried out. Spectral, magnetic, electrochemical, and catalytic behaviors of the complexes are compared on the basis of the p-substituent of the phenolic ring. Some of the complexes show significant growth inhibitory activity against pathogenic bacteria and fungi.     

Synthesis,characterization and antimicrobial studies on metal complexes with a naphthofuran thiosemicarbazide derivatives

Complexes of the type MLCl₂, where M?=?Co(II), Cu(II), Ni(II), Zn(II), Cd(II) and Hg(II) and L is a thiosemicarbazide ligand derived from reaction between naphthofuran-2-carboxyhydrazide and p-chlorophenylisothiocynate (NCClPT)/p-bromophenylisothiocynate (NCBrPT) characterized by elemental analysis, conductance, magnetic susceptibility measurements, UV-Vis, IR, ¹H?NMR, and ESR. The thiosemicarbazide ligands are bidentate by coordinating through the oxygen of the carbonyl group and the nitrogen of the hydrazide residue. Based on the results, we propose structures for all the metal complexes. Both the ligands and their complexes have been screened for their fungicidal and bactericidal activities.     

Synthesis and magnetic,spectral and thermal eukaryotic DNA studies of some 2-acetylpyridine- [N-(3-hydroxy-2-naphthoyl)] hydrazone complexes

Complexes of Ni(II), Co(II), Cu(II), Zn(II), Cd(II), Hg(II) and U(VI)O₂ with 2-acetylpyridine-[N-(3-hydroxy-2-naphthoyl)] hydrazone (H₂APHNH) have been prepared and characterized by elemental analysis, molar conductance, thermal (TG, DTG), spectral (¹H NMR, IR, UV–Vis, ESR) and magnetic measurements. ¹H NMR spectrum of the ligand suggests the presence of intramolecular hydrogen bonding. IR spectra show that H₂APHNH is a bidentate, tridentate and/or tetradentate ligand. Thermal decomposition of some complexes ended with metal oxide as a final product. ESR spectra gave evidence for the proposed structure and the bonding for some Cu(II) complexes. Biological activity measurements were carried out.     

A management oriented approach to reduce a project duration and its risk (variability)

The effects of different activities on risk and the expected completion time of a project are not the same; various activities have various effects on the successful completion of a project. Based on this fact, one of the most important issues in project management is to determine important activities and the amount of effort that should be assigned to control them, thereby completing the project successfully. In this paper, one index and one method are proposed to satisfy this necessity. Our main hypothesis is, expending effort on activities and controlling them actively results in activities risk reduction. Based on this hypothesis, the proposed index and method are compared to existing indices in the literature. Comparison results show that the proposed index and method strongly surpass other indices.     

N-硝基-N,N′-二苯基脲衍生物的合成及抑菌活性

采用“一锅法”设计合成了9个N-硝基脲衍生物,收率50.2%-76.8%。通过红外光谱、核磁共振谱及元素分析等测试技术确证了它们的结构。初步杀菌活性测试表明,当浓度为50mg/L时,部分化合物对水稻纹枯菌具有较好的抑菌活性。     

The synthesis and biological evaluation of a series of novel 2-COOC_2H_5/COONa substituted 1,5-benzothiazepine derivatives as antimicrobial agents

A series of novel 1,5-benzothiazepine derivatives containing COOC2H5/COONa groups at the C(2)-position were synthesized and evaluated for their antifungal and antibacterial activities by both disc diffusion and minimal inhibition concentration (MIC) methods. Most of the compounds have been shown to have moderate to good antibacterial activity against S. aureus, S. epidermidis and excellent antifungal activity against C. albicans.     

股票定向增发、盈余管理与公司的业绩滑坡——基于应计项目操控与真实活动操控方式下的研究

本文采用了应计项目操控与真实活动操控两种模型研究了我国上市公司定向增发新股过程中盈余管理行为以及之后的业绩表现,结果发现:中国上市公司在定向增发过程中会同时使用应计项目操控与真实活动操控两种盈余管理方式;进一步研究发现应计项目盈余管理会导致上市公司定向增发后业绩的短期滑坡,真实活动盈余管理会引起公司业绩的长期滑坡,真实活动盈余管理是上市公司定向增发之后业绩滑坡的主要原因。