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Metal complexes of fenoterol drug

Preparation, spectroscopic, thermal, and biological activity characterization

Journal of Thermal Analysis and Calorimetry
Authors: M. Soliman, Gehad Mohamed, and Eman Mohamed

10 °C min −1 using Shimadzu TG-60H and DTA-60H thermal analyzers. Synthesis of metal complexes The metal complexes were prepared by the addition of hot solution (60 °C) of the appropriate metal chloride salts (0

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azolidene carbenes to function as ligands in transition-metal complexes is well-established [ 10 , 11 ]. Consequently, biologically relevant molecules containing azoles are candidates as carbine sources for metal complexation. We consider the utilization of

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Abstract  

The mechanism of the decomposition of the entitled compounds and their complexes is studied. Adenine, its Schiff base of salicylaldehyde, and its azo resorcinol derivatives are ended with carbon. However, oxalonitrile compound is appeared as a final product for adenine acetylacetone and an intermediate for adenine. The thermodynamic parameters of the decomposition reaction were evaluated and discussed. The change of entropy values, ΔS #, showed that the transition states are more ordered than the reacting complexes. The thermal processes proceed in complicated mechanisms where the bond between the central metal ion and the ligands dissociates after losing small molecules such as H2O, NH3, or HCl. In most cases, the free radical species of the ligands are assigned to exist through decomposition mechanisms. The copper adenine and nickel salicylaldehyde complexes are ended with the metal as a final product. However, the cobalt adenine, its acetylacetone, its salicylaldehyde, cadmium and mercury guanine complexes are ended with metal oxides.

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Introduction In the recent years, the synthesis of new polymers with unusual thermal, optical, and mechanical properties has gradually gained regards. The branch of the polymer–metal complexes has been developed as an

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Transition metal complexes of heterocyclic Schiff base

Biological activity, spectroscopic and thermal characterization

Journal of Thermal Analysis and Calorimetry
Authors: M. Omar, G. Mohamed, and A. Hindy

Abstract  

Metal complexes of Schiff base derived from 2-furancarboxaldehyde and 2-aminobenzoic acid (HL) are reported and characterized based on elemental analyses, IR, 1H NMR, UV-Vis, solid reflectance, magnetic moment, molar conductance and thermal analysis. The ligand dissociation as well as the metal-ligand stability constants have been calculated pH-metrically at 25C and ionic strength μ=0.1 (1 M NaCl). The complexes are found to have the formulae [M(HL)2](X)n yH2O (where M=Fe(III) (X=Cl, n=3, y=4), Co(II) (X=Cl, n=y=2), Ni(II) (X=Cl, n=y=2), Cu(II) (X=Cl, n=y=2) and Zn(II) (X=AcO, n=y=2)) and [UO2(L)2]2H2O. The thermal behaviour of these chelates is studied and the activation thermodynamic parameters are calculated using Coats-Redfern method. The ligand and its metal complexes show a biological activity against some bacterial species.

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Abstract  

Complexes of cell–THPC–urea–ADP with transition metal ion Co2+ and lanthanide metal ions such as La3+, Ce4+, Nd3+ and Sm3+ have been prepared. The thermal behavior and smoke suspension of the samples are determined by TG, DTA, DTG and cone calorimetry. The activation energies for the second stage of thermal degradation have been obtained by following Broido equation. Experimental data show that for the complexes of cell–THPC–urea–ADP with the metal ions, the activation energies and thermal decomposition temperatures are higher than those of cell–THPC–urea–ADP, which shows these metal ions can increase the thermal stability of cell–THPC–urea–ADP. Moreover, these lanthanide metal ions can more increase thermal stability of samples than do the transition metal ion Co2+. The cone calorimetry data indicate that the lanthanide metal ions, similar to transition metal Co2+, greatly decrease the smoke, CO and CO2 generation of cell–THPC–urea–ADP, which can be used as smoke suppressants.

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Abstract  

Coal-metal complexes obtained by dynamic sorption of cations from water solution on sulphonated and oxidized coals. Complexes with the following cations were produced: Mg, Ca, Zn, Cd, Ba, Cr, Fe, Co, Ni, Cu, Pb and Ag. DTA curves of sulphonated coal and sulphonated coal-metal complexes are distinct and can be divided into three groups on the basis of shape and peak temperatures, the main influence being the type of chemical bondbetween metal cation and functional group of the coal. For metal complexes with oxidized coal the main exothermic peak shifts either to higher of lower temperatures, depending on the nature of the cations. The presence of metal chemically bound to carboxylic-and sulpho-groups of the coal causes additional thermal effects to appear on the DTA curves.

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Abstract  

The thermal behaviours of the Ti(II), Mn(II), Fe(II), Ni(II), Cu(II) and Zn(II) complexes of triethanolamine were studied by means of thermogravimetry, differential thermogravimetry, differential thermal analysis infrared spectrophotometry and elemental analysis. The sequence of thermal stability of the metal complexes, determined by using the initial decomposition temperature, was found to be Ti(II)≅Mn(II)>Fe(II)>Ni(II)>Zn(II)>Cu(II). Some of the kinetic parameters, such as the activation energy and order of reaction for the initial decomposition reaction, were calculated and the relationship between the thermal stability and the chemical structure of the complexes is discussed.

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of the literature revealed that no work has been done on transition metal complexes of the unsymmetrical Schiff base derived form acetophenones and carbohydrazide. The synthesis of unsymmetrical tetradentate Schiff base formed by the condensation of 2

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Abstract  

The atomic superposition and electron delocalization molecular orbital (ASED-MO) theory was used to calculate structures and relative stabilities of metformin-metal complexes. The relative stabilities and decomposition pathways were discussed in terms of bond order, binding energy and the nature of charge on the central metal atom. The electronic transitions and their energy gaps were also studied. The optimization of the structures shows that the most stable state is distorted from planarity for CoII and NiII complexes.

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