Synthesis, spectroscopic and biological activities studies of acyclic and macrocyclic mono and binuclear metal complexes containing a hard-soft Schiff base

Mono- and bi-nuclear acyclic and macrocyclic complexes with hard-soft Schiff base, H(2)L, ligand derived from the reaction of 4,6-diacetylresorcinol and thiocabohydrazide, in the molar ratio 1:2 have been prepared. The H(2)L ligand reacts with Co(II), Ni(II), Cu(II), Zn(II), Mn(II) and UO(2)(VI) nitrates, VO(IV) sulfate and Ru(III) chloride to get acyclic binuclear complexes except for VO(IV) and Ru(III) which gave acyclic mono-nuclear complexes. Reaction of the acyclic mono-nuclear VO(IV) and Ru(III) complexes with 4,6-diacetylresorcinol afforded the corresponding macrocyclic mono-nuclear VO(IV) and Ru(IIII) complexes. Template reactions of the 4,6-diacetylresorcinol and thiocarbohydrazide with either VO(IV) or Ru(III) salts afforded the macrocyclic binuclear VO(IV) and Ru(III) complexes. The Schiff base, H(2)L, ligand acts as dibasic with two NSO-tridentate sites and can coordinate with two metal ions to form binuclear complexes after the deprotonation of the hydrogen atoms of the phenolic groups in all the complexes, except in the case of the acyclic mononuclear Ru(III) and VO(IV) complexes, where the Schiff base behaves as neutral tetradentate chelate with N(2)S(2) donor atoms. The ligands and the metal complexes were characterized by elemental analysis, IR, UV-vis (1)H-NMR, thermal gravimetric analysis (TGA) and ESR, as well as the measurements of conductivity and magnetic moments at room temperature. Electronic spectra and magnetic moments of the complexes indicate the geometries of the metal centers are either tetrahedral, square planar or octahedral. Kinetic and thermodynamic parameters were calculated using Coats-Redfern equation, for the different thermal decomposition steps of the complexes. The ligands and the metal complexes were screened for their antimicrobial activity against Staphylococcus aureus as Gram-positive bacteria, and Pseudomonas fluorescens as Gram-negative bacteria in addition to Fusarium oxysporum fungus. Most of the complexes exhibit mild antibacterial and antifungal activities against these organisms.

Degradation of 2,4,5-trichlorophenoxyacetic acid by a novel Electro-Fe(II)/Oxone process using iron sheet as the sacrificial anode

A novel electrochemically enhanced advanced oxidation process for the destruction of organic contaminants in aqueous solution is reported in this study. The process involves the use of an iron (Fe) sheet as sacrificial anode and a graphite bar as cathode. In the oxidation process, once an electric current is applied between the anode and the cathode, a predetermined amount of Oxone is added to the reactor. Ferrous ions generated from the sacrificed Fe anode mediate the generation of highly powerful radicals (SO(4)(•-)) through the decomposition of Oxone. The coupled process of Fe(II)/Oxone and electrochemical treatment (Electro-Fe(II)/Oxone) was evaluated in terms of 2,4,5-Trichlorophenoxyacetic acid degradation in aqueous solution. Various parameters were investigated to optimize the process, including applied current, electrolyte and Oxone concentration. In addition, low solution pH facilitates the system performance due to the dual effects of weak Fenton reagent generation and persulfate ions generation, whereas the system performance was inhibited at basic pH levels through non-radical self-dissociation of Oxone and the formation of ferric hydroxide precipitates. Furthermore, the active radicals involved in the Electro-Fe(II)/Oxone process were also identified. The Electro-Fe(II)/Oxone process demonstrates a very high 2,4,5-T degradation efficiency (over 90% decay within 10 min), which justifies the novel Electro-Fe(II)/Oxone a promising treatment process for herbicide removal in water.

Degradation of a xanthene dye by Fe(II)-mediated activation of Oxone process

A powerful oxidation process using sulfate radicals activated by transition metal mediated Oxone process has been evaluated in depth by monitoring the degradation of a xanthene dye Rhodamine B (RhB) in aqueous solution. Ferrous ion was chosen as the transition metal due to its potential catalytic effect and wide availability in dyeing industrial effluent. The effects of parameters including reactant dosing sequence, Fe(II)/Oxone molar ratio and concentration, solution pH, and inorganic salts on the process performance have been investigated. Total RhB removal was obtained within 90 min under an optimal Fe(II)/Oxone molar ratio of 1:1. The RhB degradation was found to be a two-stage kinetics, consisting of a rapid initial decay and followed by a retarded stage. Additionally, experimental results indicated that the presence of certain anions had either a positive or negative effect on the process. The inhibitory effect in the presence of SO(4)(2-) was elucidated by a proposed formula using Nernst equation. Furthermore, dye mineralization in terms of TOC removal indicates that stepwise addition of Fe(II) and Oxone can significantly improve the process performance by about 20%, and the retention time required can be greatly reduced comparing with the conventional one-off dosing method.

[Synthesis, characterization and interaction with ct-DNA of four novel secondary amine complexes]

A novel ligand(L), (N, N'-bis (4-methylbenzyl) ethane-1, 2-diamine), and its transition metal(II) complex, [ML2 (H2O)2]2+ x 2NO3- (M = Cu(II), Co(II, Ni(II), Zn(II)), have been synthesized and characterized by elemental analysis, IR and 1H NMR. The crystal structure of the Cu-L complex was characterized by X-ray single crystal diffraction, and the results showed a regular octahedral structure in which each metal ion is six--coordinated with four nitrogen atoms from two ligands and two oxygen atoms from two water molecules. The interaction of the complex with calf thymus DNA was investigated by UV spectroscopy and fluorescence spectroscopy, and the results suggest that the complex binds to DNA by electrostatic interaction mode. The binding constant(Cu-L, Co-L, Ni-L, Zn-L) was 1.67 x 10(3), 2.5 x 10(3), 1.35 x 10(3) and 9.85 x 10(2), respectively.

Reactivity of heteropolytungstate and heteropolymolybdate metal transition salts in the synthesis of dimethyl carbonate from methanol and CO₂

A series of Keggin-type heteropoly compounds (HPC) having different countercations (Co, Fe) and different addenda atoms (W, Mo) were synthesized and characterized by means of Fourier-Transform Infrared Spectrometer (FT-IR) and X-ray powder diffraction (XRD). The catalytic properties of the prepared catalysts for the dimethyl carbonate (DMC) synthesis from CO₂ and CH₃OH were investigated. The experimental results showed that the catalytic activity is significantly influenced by the type of the countercation and addenda atoms transition metal. Among the catalysts examined, Co_1.5PW₁₂O₄₀ is the most active for the DMC synthesis, owing to the synergetic effect between Co and W. Investigating the effect of the support showed that the least acidic one (Al₂O₃) enhanced the conversion but decreased the DMC selectivity in favor of that of methyl formate (MF), while that of dimethoxy methane remained stable.

Transcriptional profiling of the Arabidopsis iron deficiency response reveals conserved transition metal homeostasis networks

Iron (Fe) deficiency is counteracted by a suite of responses to ensure maintenance of vital processes for which Fe is essential. Here, we report on transcriptional changes upon Fe deficiency, investigated in two Arabidopsis (Arabidopsis thaliana) accessions, Columbia (Col-0) and C24. Functional modules of the Arabidopsis Fe deficiency syndrome were inferred from clustering of Fe-responsive genes according to their coexpression. It was found that the redistribution of transition metals is an integral part of the reduction-based response to Fe starvation. The differential expression of metal transporters under the control of the FER-LIKE IRON DEFICIENCY-INDUCED TRANSCRIPTION FACTOR appeared to reflect an anticipated reaction rather than a response to the actual change in metal distribution. In contrast, the regulation of the zinc transporters ZRT/IRT-LIKE PROTEIN2 (ZIP2), ZIP3, ZIP4, and ZIP9 was dependent on the cellular zinc level, and their regulation by Fe was a secondary effect. Cellular Fe homeostasis was found to be closely coupled to Fe-related processes in the plastids. Using clustered genes as bait in gene-fishing experiments, we were able to attribute potentially important roles for gene candidates that have no previously described function in the Fe deficiency response. These results demonstrate a conceptually novel and integrative view into the regulation and interactions that allow Arabidopsis to adapt to suboptimal Fe availability.

Transcriptional profiling of the Arabidopsis iron deficiency response reveals conserved transition metal homeostasis networks

Iron (Fe) deficiency is counteracted by a suite of responses to ensure maintenance of vital processes for which Fe is essential. Here, we report on transcriptional changes upon Fe deficiency, investigated in two Arabidopsis (Arabidopsis thaliana) accessions, Columbia (Col-0) and C24. Functional modules of the Arabidopsis Fe deficiency syndrome were inferred from clustering of Fe-responsive genes according to their coexpression. It was found that the redistribution of transition metals is an integral part of the reduction-based response to Fe starvation. The differential expression of metal transporters under the control of the FER-LIKE IRON DEFICIENCY-INDUCED TRANSCRIPTION FACTOR appeared to reflect an anticipated reaction rather than a response to the actual change in metal distribution. In contrast, the regulation of the zinc transporters ZRT/IRT-LIKE PROTEIN2 (ZIP2), ZIP3, ZIP4, and ZIP9 was dependent on the cellular zinc level, and their regulation by Fe was a secondary effect. Cellular Fe homeostasis was found to be closely coupled to Fe-related processes in the plastids. Using clustered genes as bait in gene-fishing experiments, we were able to attribute potentially important roles for gene candidates that have no previously described function in the Fe deficiency response. These results demonstrate a conceptually novel and integrative view into the regulation and interactions that allow Arabidopsis to adapt to suboptimal Fe availability.

Freeze-quench (57)Fe-Mössbauer spectroscopy: trapping reactive intermediates

(57)Fe-Mössbauer spectroscopy is a method that probes transitions between the nuclear ground state (I=1/2) and the first nuclear excited state (I=3/2). This technique provides detailed information about the chemical environment and electronic structure of iron. Therefore, it has played an important role in studies of the numerous iron-containing proteins and enzymes. In conjunction with the freeze-quench method, (57)Fe-Mössbauer spectroscopy allows for monitoring changes of the iron site(s) during a biochemical reaction. This approach is particularly powerful for detection and characterization of reactive intermediates. Comparison of experimentally determined Mössbauer parameters to those predicted by density functional theory for hypothetical model structures can then provide detailed insight into the structures of reactive intermediates. We have recently used this methodology to study the reactions of various mononuclear non-heme-iron enzymes by trapping and characterizing several Fe(IV)-oxo reaction intermediates. In this article, we summarize these findings and demonstrate the potential of the method.

In-vitro biological evaluation of some ONS and NS donor Schiff's bases and their metal complexes

Complexes of Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) with the Schiff bases salicylidene-o-aminothiophenol (H2L) and thiophene-o-carboxaldeneaniline (SB) have been synthesized and characterized by elemental analyses, magnetic measurements, thermogravimetric analyses as well as infrared spectra and reflectance spectra. The nature of the bonding has been discussed on the basis of IR spectral data. Magnetic susceptibility measurements and electronic spectral data suggest a six-coordinated octahedral structure for these complexes. The complexes of Mn(II), Co(II), Ni(II), Cu(II) are paramagnetic, while Zn(II) and Cd(II) are diamagnetic in nature. The complexes were tested for their antimicrobial activities against Salmonella typhi, Escherichia coli and Serratia marcescens using the "Disc Diffusion Method". The results are compared with the standard drug (tetracycline) and show moderate activity.

Novel orientational ordering and reentrant metallicity in K(x)C(60) monolayers for 3 < or = x < or = 5

STM studies on K(x)C(60) monolayers reveal new behavior over a wide range of the phase diagram. As x increases from 3 to 5 K(x)C(60) monolayers undergo metal-insulator-metal reentrant phase transitions and exhibit a variety of novel orientational orderings, including a complex 7-molecule, pinwheel-like structure. The proposed driving mechanism for the orientational ordering is the lowering of electron kinetic energy by maximizing the overlap of neighboring molecular orbitals. In insulating (metallic) K(x)C(60) this gives rise to orbital versions of the superexchange (double-exchange) interaction.

Base- and ligand-free room-temperature synthesis of N-fused heteroaromatic compounds via the transition metal-catalyzed cycloisomerization protocol

A new practical method for the synthesis of N-fused heterocycles via the transition metal-catalyzed cycloisomerization of heterocyles possessing a propagyl group has been developed. This very mild, base- and ligand-free method allows for the synthesis of diverse fused heterocyclic cores in good to excellent yields.

Theoretical, spectroscopic, and mechanistic studies on transition-metal dinitrogen complexes: implications to reactivity and relevance to the nitrogenase problem

Dinitrogen complexes of transition metals exhibit different binding geometries of N2 (end-on terminal, end-on bridging, side-on bridging, side-on end-on bridging), which are investigated by spectroscopy and DFT calculations, analyzing their electronic structure and reactivity. For comparison, a bis(mu-nitrido) complex, where the N--N bond has been split, has been studied as well. Most of these systems are highly covalent, and have strong metal-nitrogen bonds. In the present review, particular emphasis is put on a consideration of the activation of the coordinated dinitrogen ligand, making it susceptible to protonation, reactions with electrophiles or cleavage. In this context, theoretical, structural, and spectroscopic data giving informations on the amount of charge on the N2 unit are presented. The orbital interactions leading to a charge transfer from the metals to the dinitrogen ligand and the charge distribution within the coordinated N2 group are analyzed. Correlations between the binding mode and the observed reactivity of N2 are discussed.

Semiconducting cyanide-transition-metal nanotubes

We propose a new type of structurally simple and energetically stable cyanide-transition-metal nanotube, based on the planar structure of M(CN)2, (M = Ni, Pd, Pt). These nanotubes have a semiconducting character with a large bandgap (2-3 eV) that is insensitive to chirality and diameter. The energetic, electronic, and mechanical properties of these materials in both planar and tubular forms are studied through first-principles density functional theory calculations. The calculations reveal interesting multicenter bonding features, which should lead to preferential growth of tubes of a particular chirality. These intrinsically semiconducting nanotubes can be readily p- or n-doped, which makes them good candidates for nanoscale elements in electronic devices.

Transition-metal-mediated cascade reactions: the water-accelerated carboalumination-Claisen rearrangement-carbonyl addition reaction

[Chemical reaction: See text] A three-step cascade reaction involving a water-accelerated catalytic carboalumination, a Claisen rearrangement, and a nucleophilic carbonyl addition converts terminal alkynes and allyl vinyl ethers into allylic alcohols containing up to three contiguous asymmetric carbon centers. Stoichiometric quantities of water as an additive increase the rate of the [3,3] sigmatropic rearrangement as well as the diastereoselectivity of the carbonyl addition process. Reaction products contain 1,6-diene functionalities that are readily cyclized to substituted cyclopentenes. An extension of this methodology to a sequence involving a [1,3] sigmatropic shift was feasible with a cyclopropylmethyl vinyl ether substrate.

Electronic structure of orotic acid III geometric feature and thermal properties of some transition metal orotic acid complexes

The complexes of orotic acid with Co(II), Ni(II), Fe(III), Cu(II), and Cd(II) were prepared and their stoichiometry were determined by elemental analysis. Co(II) and Ni(II) give complexes with orotic acid of 1:1 ratio whereas that of the remaining transition metals give complexes of 1:2 ratio. The stereochemistry of the studied metal complexes has been established by analyses of their electronic spectra and magnetic susceptibilities. The mode of bonding in the studied series of metal complexes was established via, analysis of their infrared spectra. The present analysis leads to the conclusion that all metal ions studied coordinate to orotic acid via N(1) and the adjacent carboxylate group. Thermal decomposition studies of orotic acid complexes have been carried out as to understand the status of water molecules present in these complexes as well as to know their general decomposition pattern. Theoretical investigation of the electronic structure of the studied metal complexes has been carried out. MO computations at the HF-level were performed. Charge density distribution, extent of distortion from regular geometry, dipole moment, and orientation were computed and discussed.

EPR spectroscopy as a probe of metal centres in biological systems

Molecular paramagnetism pervades the bioinorganic chemistry of V, Mn, Fe, Co, Ni, Cu, Mo, W, and of a number of non-biological transition elements. To date we can look back at half a century of fruitful EPR studies on metalloproteins, and against this background evaluate the significance of modern EPR spectroscopy from the perspective of a biochemist, making a distinction between conventional continuous wave X-band spectroscopy as a reliable work horse with broad, established applicability even on crude preparations, vs. a diffuse set of "advanced EPR" technologies whose practical application typically calls for narrowly focused research hypotheses and very high quality samples. The type of knowledge on metalloproteins that is readily obtainable with EPR spectroscopy, is explained with illustrative examples, as is the relation between experimental complexity and the spin value of the system.

Selected excitation for CAS-SDCI calculations

A new selected-configuration interaction method is proposed, based on the use of local orbitals. A corresponding code has been written, which is devoted to CI calculations of rather large systems (about 50-100 carbon-like atoms). Taking advantage of the locality, and then of the fact that interactions vanish when the distance is large, the dimension of the CI space is largely reduced. The determinants that would be created by long range excitations are expected to have a small weight in the wave function and are therefore eliminated. This selected excitation CI space is particularly suited for large molecules. It is tested on large polyene chains and on a transition metal complex. For large enough systems, the CPU time saving is important and, what is more noticeable, calculations that were impossible to perform without selection are feasible in this approach.

Amyloid-β: Acute-phase apolipoprotein with metal-binding activity

In monomeric form, amyloid-beta (Abeta), an amphipatic 4 kDa peptide which plays a key role in the pathogenesis of Alzheimer's disease (AD), is associated with lipoproteins in biological fluids and possesses high affinity to transition metal ions; in addition, synthesis of Abeta is upregulated under acute phase conditions. These data suggest that Abeta can be regarded as a normal physiological component of lipoproteins and may represent an acute-phase apolipoprotein with metal-binding activity. Interaction with transition metal ions may cause aggregation of Abeta, leading to formation of oligomers. Such oligomerised Abeta may lose its normal biological functions and acquire deleterious activities. To be efficient, novel anti-AD therapies should target oligomeric forms of Abeta while preserving the monomeric form of the peptide.

Mixed ligand complexes of bis(phenylimine) Schiff base ligands incorporating pyridinium moiety Synthesis, characterization and antibacterial activity

The synthesis and structural characterization of mixed ligand complexes derived from 2,6-pyridinedicarboxaldehydebis(o-hydroxyphenylimine), 2,6-pyridinedicarboxaldehydebis(p-hydroxyphenylimine) (1(ry) ligands) and 2-aminopyridne (2(ry) ligand) are reported. The ligands and their transition metal complexes were characterized on the bases of their elemental analyses, IR, solid reflectance, magnetic moment, molar conductance and thermal analysis (TGA). The mixed ligand complexes are formed in the 1:1:1 (M:L(1) or L(2):L') ratio as found from the elemental analyses and found to have the formulae [MX(2)(L(1) or L(2))(L')].nH(2)O where M = Co(II), Ni(II), Cu(II) and Zn(II), L(1) = 2,6-pyridinedicarboxaldehydebis(p-hydroxyphenylimine), L(2) = 2,6-pyridine dicarboxaldehydebis(o-hydroxyphenylimine), L' = 2-aminopyridine, X = Cl(-) in case of Cu(II) complex and Br(-) in case of Co(II), Ni(II) and Zn(II) complexes and y = 0-3. The molar conductance data reveal that the chelates are non-electrolytes. IR spectra show that the Schiff bases are coordinated to the metal ions in a terdentate manner with NNN donor sites of the pyridine-N and two azomethine-N. While 2-aminopyridine coordinated to the metal ions via its pyridine-N. Magnetic and solid reflectance spectra are used to infer the coordinating capacity of the ligand and the geometrical structure of these complexes are found to be octahedral. The thermal behaviour of these chelates shows that the hydrated water molecules and the anions are removed in a successive two steps followed immediately by decomposition of the ligands (L(1), L(2) and L') in the subsequent steps. The activation thermodynamic parameters, such as, E*, DeltaH*, DeltaS* and DeltaG* are calculated from the TG curves and discussed. The ligands and their metal chelates have been screened for their antimicrobial activities and the findings have been reported, explained and compared with some known antibiotics.

Perturbation of the PET Process in Fluorophore−Spacer−Receptor Systems through Structural Modification: Transition Metal Induced Fluorescence Enhancement and Selectivity

Several fluorescent signaling systems are built in the format fluorophore-spacer-receptor with ethylenediamine or N,N-dimethylethylenediamine as the receptor, anthracene as the fluorophore, and a methylene group as the spacer. The receptors are derivatized with different electron-withdrawing groups such as 4-nitrobenzene, 4-nitro-2-pyridine, and 2,4-dinitrobenzene, to perturb the photoinduced intramolecular electron transfer (PET) process from the nitrogen lone-pair to the fluorophore. The photophysical properties of these supramolecular systems and their fluorescence responses toward a number of quenching transition metal ions are reported. It is shown that the PET is highly efficient in the absence of a metal ion. With a metal ion input, the fluorescence can be recovered to a different extent depending on the nature of the metal and on the overall architecture of the system as well. Despite the possibility of strong interaction between the fluorophore and the metal ion, significant fluorescence enhancement is observed with quenching of paramagnetic transition metal ions. The complex stability data show that the stability constants for the metal ions showing fluorescence enhancement are of the order of 10(4) M(-1). This study shows that structurally simple fluorescent signaling systems for quenching transition metal ions can be built by maximizing the PET. It is also shown here that simple structural modification can make these systems highly specific for particular transition metal ions for potential applications in several contemporary areas of research.

Surface and Subsurface Hydrogen: Adsorption Properties on Transition Metals and Near-Surface Alloys

Periodic, self-consistent DFT-GGA calculations are used to study the thermochemical properties of both surface and subsurface atomic hydrogen on a variety of pure metals and near-surface alloys (NSAs). For surface hydrogen on pure metals, calculated site preferences, adsorption geometries, vibrational frequencies, and binding energies are reported and are found to be in good agreement with available experimental data. On NSAs, defined as alloys wherein a solute is present near the surface of a host metal in a composition different from the bulk composition, surface hydrogen generally binds more weakly than it binds to the pure-metal components composing the alloys. Some of the NSAs even possess the unusual property of binding hydrogen as weakly as the noble metals while, at the same time, dissociating H(2) much more easily. On both NSAs and pure metals, formation of surface hydrogen is generally exothermic with respect to H(2)(g). In contrast, formation of subsurface hydrogen is typically endothermic with respect to gas-phase H(2) (the only exception to this general statement is found for pure Pd). As with surface H, subsurface H typically binds more weakly to NSAs than to the corresponding pure-metal components of the alloys. The diffusion barrier for hydrogen from surface to subsurface sites, however, is usually lower on NSAs compared to the pure-metal components, suggesting that population of subsurface sites may occur more rapidly on NSAs.

[Electron spectra of chemical assembly mesoporous MCM-41 with transition metal complexes]

In the paper the complexes of metal cobalt(III), manganese(III), iron(III) and copper(II) with Schiff-base N,N-ethylenebis(salicylideneaminnato) have been synthesized and characterized. The nanosized porous material MCM-41 has been functionalized by the modification of the internal pore surface with gamma-aminopropyl and was assembled by the modification groups with metal complex of Schiff-base. These metal complexes and functionalized nanosized porous materials were charcterized by XRD, IR and UV-Vis. It is indicated by spectral analysis that the synthesized nanosized porous materials have been confirmed to be MCM-41 with hexagon bores, and the gamma-aminopropyls have been bonded on their internal pore surface. And the complexes of metal cobalt(III), manganese(III), iron(III) and copper(II) with Schiff-base N,N-ethylenebis(salicylideneaminnato) were assembled into MCM-41. The IR spectra of these samples show that there were characteristic absorptions of the amino and the Schiff base groups, and the absorption of amino shifted to longer wavelength.

Derivatives of phosphate Schiff base transition metal complexes: synthesis, studies and biological activity

We report the synthesis and structural characterization of series of tetra- and hexacoordinate metal chelate complexes of phosphate Schiff base ligands having the general composition LMX(n).H(2)O and L(2)MX(n) (L=phosphate Schiff base ligand; M=Ag(+), Mn(2+), Cu(2+), Zn(2+), Cd(2+), Hg(2+), or Fe(3+) and X=NO(3)(-), Br(-) or Cl(-)). The structure of the prepared compounds was investigated using elemental analysis, IR, 1H and 31P NMR, UV-vis, mass spectra, solid reflectance, magnetic susceptibility and conductance measurements as well as conductometric titration. In all the complexes studied, the ligands act as a chelate ligand with coordination involving the phosphate-O-atom and the azomethine-N-atom. IR, solid reflectance spectra and magnetic moment measurement are used to infer the structure and to illustrate the coordination capacity of ligand. IR spectra show the presence of coordinated nitrate and water molecule, the magnetic moments of all complexes show normal magnetic behavior and the electronic spectra of the metal complexes indicate a tetra- and octahedral structure for Mn(2+), octahedral structure of Fe(3+) and both square-planar and distorted octahedral structure for Cu(2+) complexes. Antimicrobial activity of the ligands and their complexes were tested using the disc diffusion method and the chosen strains include Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Microsporum canis, Trichophyton mentagrophyte and Trichophyton rubrum. Some known antibiotics are included for the sake of comparison and the chosen antibiotic are Amikacin, Doxycllin, Augmantin, Sulperazon, Unasyn, Septrin, Cefobid, Ampicillin, Nitrofurantion, Traivid and Erythromycin.