Rania Zaky

Co(II), Cd(II), Hg(II) and U(VI)O2 complexes of o-hydroxyacetophenone[N-(3-hydroxy-2-naphthoyl)] hydrazone: Physicochemical study, thermal studies and antimicrobial activity

The o-Hydroxy acetophenone [N-(3-hydroxy-2-naphthoyl)] hydrazone (H(2)o-HAHNH) has been prepared and its structure is confirmed by elemental analysis, IR, (1)H NMR and (13)C NMR spectroscopy. It has been used to produce diverse complexes with Co(II), Cd(II), Hg(II) and U(VI)O(2) ions. The isolated complexes have been investigated by elemental analysis, magnetic measurements, molar conductivity, thermal (TG, DTG) and spectral ((1)H NMR, (13)C NMR, IR, UV-visible, MS) studies. Infrared spectra suggested H(2)o-HAHNH acts as a bidentate and/or tridentate ligand. The electronic spectrum of [Co(Ho-HAHNH)(2)] complex as well as its magnetic moments suggesting octahedral geometry around Co(II) center. The TG analyses suggest high stability for most complexes followed by thermal decomposition in different steps. Moreover, the kinetic and thermodynamic parameters (Ea, A, ΔH, ΔS and ΔG) for the different decomposition steps of the [Co(Ho-HAHNH)(2)] and [Cd(Ho-HAHNH)(2)] complexes were calculated using the Coats-Redfern and Horowitz-Metzger methods. Moreover, the antibacterial and antifungal activities of the isolated compounds were studied using a wide spectrum of bacterial and fungal strains.

Bivalent transition metal complexes of o-hydroxyacetophenone [N-(3-hydroxy-2-naphthoyl)] hydrazone: Spectroscopic, antibacterial, antifungal activity and thermogravimetric studies

Schiff base complexes of Cu(II), Ni(II) and Zn(II) with the o-hydroxyacetophenone [N-(3-hydroxy-2-naphthoyl)] hydrazone (H(2)o-HAHNH) containing N and O donor sites have been synthesized. Both ligand and its metal complexes were characterized by different physicochemical methods, elemental analysis, molar conductivity ((1)H NMR, (13)C NMR, IR, UV-visible, ESR, MS spectra) and also thermal analysis (TG and DTG) techniques. The discussion of the outcome data of the prepared complexes indicates that the ligand behave as a bidentate and/or tridentate ligand. The electronic spectra of the complexes as well as their magnetic moments suggest octahedral geometries for all isolated complexes. The room temperature solid state ESR spectrum of the Cu(II) complex shows d(x2-y2) as a ground state, suggesting tetragonally distorted octahedral geometry around Cu(II) centre. The molar conductance measurements proved that the complexes are non-electrolytes. The kinetic thermodynamic parameters such as: E(#), ΔH(#), ΔG(#), ΔS(#) are calculated from the DTG curves, for the [Ni(H(O)-HAHNH)(2)] and [Zn(H(2O)-HAHNH)(OAc)(2)]·H(2)O complexes using the Coats-Redfern equation. Also, the antimicrobial properties of all compounds were studied using a wide spectrum of bacterial and fungal strains. The [Cu(Ho-HAHNH)(OAc)(H(2)O)(2)] complex was the most active against all strains, including Aspergillus sp., Stemphylium sp. and Trichoderma sp. Fungi; E. coli and Clostridium sp. Bacteria.

Bivalent transition metal complexes of (E)-3-(2-benzylidenehydrazinyl)-3-oxo-N-(p-tolyl)propanamide: Spectroscopic, computational, biological activity studies

Schiff base complexes of Co(II), Ni(II) and Cu(II) with (E)-3-(2-benzylidenehydrazinyl)-3-oxo-N-(p-tolyl)propanamide (H2BHAH) containing N and O donor sites were synthesized. Both ligand and its metal complexes were characterized by elemental analysis, thermal analysis (TG and DTG), spectroscopy ((1)H NMR, IR, UV-visible, MS spectra), and physical measurements (magnetic susceptibility and molar conductance). The kinetic and thermodynamic parameters of the different decomposition steps of some complexes were calculated using the Coats-Redfern and Horowitz-Metzger methods. Also, the DFT studying was evaluated to confirm the geometry of the investigated compounds. Moreover, the association and formation constants of Ni(II) and Cu(II) ions in mixed solvent at 290.15K were calculated by using electrical conductance. The antimicrobial activities of the ligand and its complexes were studied against gram positive bacteria Staphylococcus aureus, gram negative bacteria; Escherichia coli and pathogenic fungi; Candida albicans by using minimum inhibition concentrations method. The antioxidant (ABTS-derived free radical method) and cytotoxic (in vitro Ehrlich Ascites) activities of the isolated compounds were estimated.

Physicochemical studies and biological evaluation on (E)-3-(2-(1-(2-hydroxyphenyl)hydrazinyl)-3-oxo-N-(thiazol-2yl)propanamide complexes.

Hydrazone complexes of Co(II), Ni(II), Cu(II), Pd(II), Cd(II), Zn(II) and U(VI)O2 with (E)-3-(2-(1-(2-hydroxyphenyl)hydrazinyl)-3-oxo-N-(thiazol-2yl)propanamide (H2o-HAH) have been synthesized. The complex structure has been elucidated by analysis (elemental and thermal), spectroscopy ((1)H NMR, (13)C NMR, IR, UV-visible, ESR, MS) and physical measurements (magnetic susceptibility and molar conductance). The kinetic and thermodynamic parameters for the different decomposition steps of some complexes have been calculated using the Coats-Redfern equation. Also, the association and formation constants of Co(II) ion in absolute ethanol solutions at 294.15K have been calculated by using electrical conductance. Moreover, the ligand and its complexes have been screened for their antibacterial (Escherichia coli and Clostridium sp.) and antifungal activities (Aspergillus sp. and Stemphylium sp.) by MIC method.

Computational studies of the first order kinetic reactions for mononuclear copper(II) complexes having a hard-soft NS donor ligand.

The chelation behaviour of 4-((E)-2-(1-(thiophen-2-yl)ethylidene)hydrazinyl)-1-(4-methoxyphenyl)-1H-pyrrole-3-carbonitrile (HL) towards Cu(II) ions has been investigated. These Cu(II) complexes are characterized by elemental analyses, molar-solid conductance, ESR, FTIR and electronic spectral studies. Also, the kinetic and thermodynamic parameters (Ea, A, ΔH, ΔS, ΔG) for all thermal decomposition steps have been evaluated using Coats-Redfern and Horowitz-Metzger methods. Furthermore, antimicrobial activity of the ligand and its complexes were studied against Gram-negative bacteria: Escherichia coli, Gram-positive Bacillus cereus, Bacillus subtilis and pathogenic fungi Pseudomonas aeruginosa by using minimum inhibitory concentrations (MICs) method.

Bivalent transition metal complexes of 3-(2-(4-(dimethylamino)benzylidene)hydrazinyl)-3-oxo-N-(thiazol-2-yl)propanamide: Structural, spectral, DFT, ion-flotation and biological studies

Abstract Co(II), Pb(II), Hg(II) and Cd(II) complexes of the 3-(2-(4-(dimethylamino)benzylidene)hydrazinyl)-3-oxo-N-(thiazol-2-yl)propanamide (H2L) were synthesized. The prepared compounds were interpreted by elemental analysis: C, H, N, M, Cl; physical measurements as molar conductance; and magnetic susceptibility spectroscopic techniques as IR, UV–visible, 1H NMR, MS spectra. The computational studying was estimated to approve the geometry of the isolated solid compounds. Also, Pb(II) and Cd(II) were separated using a simple, rapid and inexpensive quantitative flotation method prior to their determinations using atomic absorption spectrophotometric (AAS). The main parameters influencing the flotation process were examined (ca. initial pH, metal ion, surfactant and ligand concentrations, presence of foreign ions, and temperature). Furthermore, the biological activity (antimicrobial, anti-oxidant and cytotoxic) of the investigated compounds was tested.

Solid state ball milling as a green approach to prepare Cu(II) complexes: structural, spectral, DFT, and DNA studies

An effective and environmentally friendly ball milling method was used to prepare a series of organometallic compounds. The isolated compounds were characterized via a number of physical and spectroscopic methods. The DNA affinity probe assay was used to examine the antitumor activity of the tested compounds.

Solvent-free mechanochemical synthesis of Zn(II), Cd(II), and Cu(II) complexes with 1-(4-methoxyphenyl)-4-(2-(1-(pyridin-2-yl)ethylidene)hydrazinyl)-1H-pyrrole-3-carbonitrile

Abstract Zn(II), Cd(II), and Cu(II) complexes with 1-(4-methoxyphenyl)-4-(2-(1-(pyridin-2-yl)ethylidene)hydrazinyl)-1H-pyrrole-3-carbonitrile (HP) were produced by using ball milling as a mechanochemical technique. The mode of chelation for the isolated complexes was illustrated by several spectroscopic techniques. Also, a computational study was estimated to prove the geometry of the isolated complexes by applying a density function theory method. In addition, its biological activity (antimicrobial and DNA binding) was evaluated.

2-(2-(2-Hydroxybenzyliden) Hydrazinyl)-2-Oxo-N-(Pyridine-2-Yl)Acetamide Complexes: Synthesis, Characterization and Biological Studies

2-(2-(2-hydroxybenzyliden) hydrazinyl)-2-oxo-N-(pyridine-2-yl) acetamide complexes of Ni(II) and Co(II) prepared. The proposed structures proved based on elemental, DFT, and spectral analysis. The DNA binding affinity and MIC activity against Gram-positive, Gram-negative bacteria, pathogenic C. albicans and A. flavus fungal strain tested.