Desenvolvimento de compostos de coordenação para aplicação foliar e elucidação do mecanismo de absorção / Development of coordination compounds for foliar application and elucidation of the absorption mechanism

O objetivo geral desse trabalho foi desenvolver compostos de coordenação com os metais cobre, manganês, zinco, cobalto, níquel e magnésio com os aminoácidos L- ácido aspártico e glutâmico para aplicação como fertilizantes foliares e elucidação de seus prováveis mecanismos de absorção pela planta. Como plano de trabalho, pretendeu-se produzir alguns complexos metálicos com agentes complexantes que confiram características específicas: alta estabilidade termodinâmica e cinética quando comparado a quelatos usados comercialmente dos mesmos metais; alta solubilidade; compatibilidade com herbicidas e fungicidas e alta estabilidade frente a variações de pH. Os compostos foram caracterizados no estado sólido e/ou em solução aquosa, através de técnicas disponíveis em nosso laboratório, na Central Analítica do IQ-USP e/ou nos laboratórios da ICL América do Sul Ind. e Com. SA. Com o desenvolvimento dos compostos de coordenação, foram avaliados alguns parâmetros considerados imprescindíveis para garantia da qualidade do produto gerado, que foram então comparados aos de quelatos de EDTA (ácido etilenodiaminotetraacético) comercializados atualmente e que demonstraram vantagens. Para avaliar a eficiência dos produtos gerados foi realizada aplicação foliar em ao menos uma cultura e verificado o teor de cada nutriente após período de absorção e resposta produtiva, evidenciando e determinando o mecanismo de absorção realizado pela planta. Como resultado, desenvolveu-se uma série de produtos com alta tecnologia agregada que trouxeram benefícios nutricionais, sustentando uma nutrição de qualidade além de serem ecologicamente favoráveis (eco-friendly portfolio)

This project aims the development of copper, manganese, zinc, cobalt, nickel and iron metal complexes with L-amino acids aspartic and glutamic acids for application as foliar fertilizers and elucidation of the probable incorporation/absorption mechanism by plants. As a work plan, it was intended to produce these metal complexes with complexing agents that provide specific characteristics: high thermodynamic and kinetic stabilities when compared to the corresponding EDTA chelates; high solubility; compatibility with herbicides and fungicides and high stability against pH variations. With the development of such coordination compounds, some parameters considered indispensable to quality assurance were then evaluated, in comparison to that of currently available commercial EDTA chelates. To evaluate the performance of the obtained compounds, two foliar applications in the same crop were carried out. Further, the content of each nutrient after the production period and the productive capacity were evaluated, aiming to elucidate the absorption mechanism of the plant. As a result, elaborated products with high added technology were obtained, capable of ameliorating the nutritional benefits, that can support an eco-friendly portfolio

Synthesis, characterization and theoretical calculations of Cu(I) complex of trithiocyanuric acid [Cu(ttc)3] / Síntesis, caracterización y cálculos teóricos del complejo Cu(I) de ácido cianúrico [Cu(ttc)3] / Síntese, caracterização e cálculos teóricos do complexo Cu(I) de ácido cianúrico [Cu(ttc)3]

Abstract A new Cu(I) complex constructed by reaction of trithiocyanuric acid (ttc) and copper(II) perchlorate hexahydrate has been successfully synthesized by a slow sedimentation method in a DMF solvent at room temperature. The molecular structure of the compound was elucidated by MALDI-TOF MS, UV-Vis and FTIR spectroscopy, DSC-TGA analysis and magnetic susceptibility measurement. The proposed structure was corroborated by a computational study carried out with the Gaussian09® and AIMAII® programs using the RB3LYP hybrid DFT functional with both 6-31G and Alhrich-TZV basis sets. The calculated vibrational frequencies values were compared with experimental FTIR values. Photophysical properties of the synthesized complex were evaluated by UV-Visible spectroscopy and compared with computed vertical excitation obtained from TDDFT. The theoretical vibrational frequencies and the UV-Vis spectra are in good agreement with the experimental values. Additionally, the Frontier Molecular Orbitals (HOMO - LUMO) and the Molecular Electrostatic Potential of the complex was calculated using same theoretical approximation. The results showed the interaction between three coordinated ligand atoms and the Cu(I) ion.

Resumen Un nuevo complejo de Cu(I) elaborado por la reacción de ácido cianúrico (ttc) y perclorato de cobre(II) hexahidrato se sintetizó exitosamente por medio de un método lento de sedimentación en un solvente de DMF a temperatura ambiente. La estructura molecular del compuesto se determinó utilizando MS de MALDI-TOF, la espectroscopia de UV-VIS y de FTIR, el análisis de DSC-TGA y el análisis magnético de susceptibilidad. La estructura propuesta se corroboró por medio de un estudio computacional usando los programas Gaussian09® y AIMAII®, utilizando el híbrido RB3LYP DFT con los equipos 6-31G y Alhrich-TZV. Se compararon los valores calculados de las frecuencias vibracionales con los valores experimentales de FTIR. Se evaluaron las características fotofísicas del complejo sintetizado usando espectroscopia UV-visible y se compararon con la vibración vertical obtenida de TDDFT. Las frecuencias teóricas vibracionales y los espectros UV-VIS coinciden con los valores experimentales. Además, se calcularon las órbitas moleculares (HOMO - LUMO) y el potencial electrostático molecular del complejo usando la misma aproximación teórica. Los resultados demostraron la interacción entre tres receptores de átomos coordinados y el ion del Cu(I).

Resumo Um novo complexo de Cu(I) elaborado pela reação de ácido cianúrico (ttc) e perclorato de cobre (II) hexahidratado foi sintetizado de maneira exitosa por meio de um método lento de sedimentação em um solvente de DMF a temperatura ambiente. A estrutura molecular do composto se determinou utilizando MALDI-TOF, espectroscopia de UV-VIS e FTIR, DSC-TGA e análise magnético de susceptibilidade. A estrutura proposta se corroborou por meio de um estudo computacional usando os programas Gaussian09® e AIMAII®, utilizando o híbrido RB3LYP DFT com os equipamentos 6-31G e Alhirich-TZV. Se compararam os valores calculados das frequências vibracionais com os valores experimentais de FTIR. Se avaliaram as características fotofísicas do complexo sintetizado utilizando espectroscopia UV-VIS e se compararam com a vibração vertical obtida de TDDFT. As frequências teóricas vibracionais e os espectros UV-VIS coincidem com os valores experimentais. Além disso, se calcularam as órbitas moleculares (HOMO - LUMO) e o potencial eletrostático molecular do complexo utilizando a mesma aproximação teórica. Os resultados demonstraram a interação entre três receptores de átomos coordenados e o íon de Cu(I).

Synthesis, crystal structure, and anti-breast cancer activity of a novel metal-porphyrinic complex [YK(TCPP)(OH)2·(solvents)x]

A novel heterometallic metal-porphyrinic framework (MPFs) built from Y and K ions as nods and meso-tetra(4-carboxyphenyl)porphyrin as linkers has been successfully synthesized and characterized. The single crystal X-ray diffraction indicated that this complex 1 exhibited a bilayered architecture of the porphyrins, which is seldom seen in MPFs. In addition, in vitro anticancer activity of complex 1 on three human breast cancer cells (BT474, SKBr-3 and ZR-75-30) was further determined.

Antiplasmodial activity of iron(II) and ruthenium(II) organometallic complexes against Plasmodium falciparum blood parasites

This work reports the in vitro activity against Plasmodium falciparumblood forms (W2 clone, chloroquine-resistant) of tamoxifen-based compounds and their ferrocenyl (ferrocifens) and ruthenocenyl (ruthenocifens) derivatives, as well as their cytotoxicity against HepG2 human hepatoma cells. Surprisingly with these series, results indicate that the biological activity of ruthenocifens is better than that of ferrocifens and other tamoxifen-like compounds. The synthesis of a new metal-based compound is also described. It was shown, for the first time, that ruthenocifens are good antiplasmodial prototypes. Further studies will be conducted aiming at a better understanding of their mechanism of action and at obtaining new compounds with better therapeutic profile.

A novel schiff base zinc coordination compound inhibits proliferation and induces apoptosis of human osteosarcoma cells / 华中科技大学学报（医学）（英德文版）

Various kinds of schiff base metal complexes have been proven to induce apoptosis of tumor cells. However, it remains largely unknown whether schiff base zinc complexes induce apoptosis in human cancer cells. Here, we synthesized a novel schiff base zinc coordination compound (SBZCC) and investigated its effects on the growth, proliferation and apoptosis of human osteosarcoma MG-63 cells. A novel SBZCC was synthesized by chemical processes and used to treat MG-63 cells. The cell viability was determined by CCK-8 assay. The cell cycle progression, mitochondrial membrane potential and apoptotic cells were analyzed by flow cytometry. The apoptosis-related proteins levels were determined by immunoblotting. Treatment of MG-63 cells with SBZCC resulted in inhibition of cell proliferation and cell cycle arrest at G1 phase. Moreover, SBZCC significantly reduced the mitochondrial membrane potential and induced apoptosis, accompanied with increased Bax/Bcl-2 and FlasL/Fas expression as well as caspase-3/8/9 cleavage. Our results demonstrated that the synthesized novel SBZCC could inhibit the proliferation and induce apoptosis of MG-63 cells via activating both the mitochondrial and cell death receptor apoptosis pathways, suggesting that SBZCC is a promising agent for the development as anticancer drugs.

Integrated Whole Body MR/PET: Where Are We?

Whole body integrated magnetic resonance imaging (MR)/positron emission tomography (PET) imaging systems have recently become available for clinical use and are currently being used to explore whether the combined anatomic and functional capabilities of MR imaging and the metabolic information of PET provide new insight into disease phenotypes and biology, and provide a better assessment of oncologic diseases at a lower radiation dose than a CT. This review provides an overview of the technical background of combined MR/PET systems, a discussion of the potential advantages and technical challenges of hybrid MR/PET instrumentation, as well as collection of possible solutions. Various early clinical applications of integrated MR/PET are also addressed. Finally, the workflow issues of integrated MR/PET, including maximizing diagnostic information while minimizing acquisition time are discussed.

The molecular mechanism between baicalin metal complexes and bovin serum album / 药学学报

In this paper, the new carbon nanotube modified glassy carbon electrode (F-CNTs/GCE) was prepared to establish a new method for studying the molecular interaction mechanism between baicalin metal complexes (BMC) and bovine serum album (BSA), and the principle of this method was discussed deeply. Under the physiological condition, the thermodynamics and kinetics properties of interaction between BMC and BSA were studied by cyclic voltammetry (CV) to inference their molecular effective mechanism. The results show that the presence of F-CNTs can accelerate the electron transfer, and better response signal was showed in the BMC/BMC-BSA system. The detection of interaction of BMC-BSA used new method show that BMC-BSA generates stable thermodynamically non-covalent compounds, and the obtained average binding sites of BMC-BSA were 1.7; the number of electron transfer in BMC/BMC-BSA reaction process was 2, and non electroactive supramolecular compounds of BMC-BSA were generated by this interacting reaction. The relevant research work provides a new way to study the molecular mechanism for the interaction of drugs with protein, and with a certain reference value for discussion on the non covalent interactions.

Target-directed catalytic metallodrugs

Most drugs function by binding reversibly to specific biological targets, and therapeutic effects generally require saturation of these targets. One means of decreasing required drug concentrations is incorporation of reactive metal centers that elicit irreversible modification of targets. A common approach has been the design of artificial proteases/nucleases containing metal centers capable of hydrolyzing targeted proteins or nucleic acids. However, these hydrolytic catalysts typically provide relatively low rate constants for target inactivation. Recently, various catalysts were synthesized that use oxidative mechanisms to selectively cleave/inactivate therapeutic targets, including HIV RRE RNA or angiotensin converting enzyme (ACE). These oxidative mechanisms, which typically involve reactive oxygen species (ROS), provide access to comparatively high rate constants for target inactivation. Target-binding affinity, co-reactant selectivity, reduction potential, coordination unsaturation, ROS products (metal-associated vs metal-dissociated; hydroxyl vs superoxide), and multiple-turnover redox chemistry were studied for each catalyst, and these parameters were related to the efficiency, selectivity, and mechanism(s) of inactivation/cleavage of the corresponding target for each catalyst. Important factors for future oxidative catalyst development are 1) positioning of catalyst reduction potential and redox reactivity to match the physiological environment of use, 2) maintenance of catalyst stability by use of chelates with either high denticity or other means of stabilization, such as the square planar geometric stabilization of Ni- and Cu-ATCUN complexes, 3) optimal rate of inactivation of targets relative to the rate of generation of diffusible ROS, 4) targeting and linker domains that afford better control of catalyst orientation, and 5) general bio-availability and drug delivery requirements.

Absorption, distribution and elimination of (59)Fe- corn polysaccharide iron complex in rats: a study with radioactivity isotope tracing / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a method for detecting plasma concentration of corn polysaccharide iron complex (CPIC) and investigate its absorption, distribution and elimination in rats.</p><p><b>METHODS</b>Using radioactivity isotope tracing method, we detected the radioactivity of (59)Fe-CPIC in the plasma of rats at different time points by gavages of 3 doses (28.0, 14.0, and 7.0 mg/kg) (59)Fe-CPIC in SD rats. The pharmacokinetic parameters was obtained using DAS 2.0 program for analysis of tissue distribution and elimination of (59)Fe-CPIC.</p><p><b>RESULTS</b>The standard curve was linear within the range of 0.14-141 µg/ml (r=0.9999, n=5). The average recovery was 95% with a relative standard deviation no more than 15%. The pharmacokinetic parameters at 3 doses obtained, namely t1/2 and AUC (0-), were 214∓104, 231∓110, and 181∓81 min, and 1986.3∓513.3, 737.0∓467.0, and 315.1∓226.1 mg·min-1·L(-)1, respectively. (59)Fe-CPIC were detected in all the 13 tissues types examined and high radioactivity intensity was found in the gastrointestinal tract, hematogenic organs and other organs rich in blood. (59)Fe-CPIC was eliminated after intragastric administration primarily via the feces in rats.</p><p><b>CONCLUSION</b>The method we established is easy and specific, and the pharmacokinetic parameters of (59)Fe-CPIC fit the two- compartment open model.</p>

Synthesis of New VO(II), Co(II), Ni(II) and Cu(II) Complexes with Isatin-3-Chloro-4-Floroaniline and 2-Pyridinecarboxylidene-4-Aminoantipyrine and their Antimicrobial Studies

The complexes of tailor made ligands with life essential metal ions may be an emerging area to answer the problems of multi drug resistance. The coordination complexes of VO(II), Co(II), Ni(II) and Cu(II) with the Schiff bases derived from isatin with 3-chloro-4-floroaniline and 2-pyridinecarboxaldehyde with 4-aminoantipyrine have been synthesized by conventional as well as microwave methods. These compounds have been characterized by elemental analysis, molar conductance, electronic spectra, FT-IR, FAB mass and magnetic susceptibility measurements. FAB mass data show degradation of complexes. Both the ligands behave as bidentate and tridentate coordinating through O and N donor. The complexes exhibit coordination number 4, 5 or 6. The Schiff base and metal complexes show a good activity against the bacteria; Staphylococcus aureus, Escherichia coli and Streptococcus fecalis and fungi Aspergillus niger, Trichoderma polysporum, Candida albicans and Aspergillus flavus. The antimicrobial results also indicate that the metal complexes are better antimicrobial agents as compared to the Schiff bases. The minimum inhibitory concentrations of the metal complexes were found in the range 10~40 microg/mL.

Advance of studies on bioactivity of flavonoid-metal complexes / 中国中药杂志

The flavonoid-metal complexes showed obviously stronger bioactivities such as antibiosis, antivirus, anti-inflammatory, anti-tumor and anti-free-radical, possibly because of the stronger binding force caused by the change in complex structure and accessibility to target spots, or the synergy effect between flavonoids and metallic ions. This essay summarizes studies on bioactivity and mechanism of flavonoid-metal complexes, in order to provide reference for in-depth study and development on effective constituents contained in flavonoid traditional Chinese medicines.

Effects of Rut-bpy (Cis-[Ru(bpy)2(SO3)(NO)]PF 6), a novel nitric oxide donor, in L-NAME-induced hypertension in rats / Efeitos do Rut-bpy (Cis-[Ru(bpy)2(SO3)(NO)]PF 6), um novo doador de óxido nítrico, na hipertensão induzida com L-NAME em ratos

PURPOSE: To evaluate the effect of Rut-bpy (Cis-[Ru(bpy)2(SO3)(NO)]PF 6), a novel nitric oxide donor in Nω-nitro-L-arginine methyl ester (L-NAME)-induced hypertensive rats. METHODS: Twenty-four male Wistar rats were randomly assigned to four groups (n=6), named according to the treatment applied (G1-Saline, G2-Rut-bpy, G3-L-NAME and G4-L-NAME+Rut-bpy). L-NAME (30 mg/Kg) was injected intraperitoneally 30 minutes before the administration of Rut-bpy (100 mg/Kg). Mean abdominal aorta arterial blood pressure (MAP) was continuously monitored. RESULTS: Mean arterial blood pressure (MAP) in G3 rats rose progressively, reaching 147±16 mmHg compared with 100±19 mm Hg in G1 rats (p<0.05). In G4 rats, treated with L-NAME+Rut-bpy, MAP reached 149+11 mm Hg while in G2 rats, treated with Rut-bpy, MAP values were 106±11 mm Hg. In G1 rats these values decreased progressively reaching 87+14 mm Hg after 30 minutes. An important finding was the maintenance of the MAP throughout the experiment in G2 rats. CONCLUSION: Rut-bpy does not decrease the MAP in L-Name induced hypertensive rats. However, when it is used in anesthetized hypotensive rats a stable blood pressure is obtained.

OBJETIVO: Avaliar o efeitos do Rut-bpy (Cis-[Ru (bpy)2(SO3)(NO)] PF6), um novo doador de óxido nítrico, em ratos hipertensos induzidos pelo éster metílico de N-nitro-L-arginina (L-NAME). MÉTODOS: Vinte e quatro ratos Wistar machos foram distribuídos aleatoriamente em quatro grupos (n = 6), nomeados de acordo com o tratamento aplicado (G1-Salina, G2-Rut-bpy, G3-L-NAME e G4-L-NAME+Rut -bpy). L-NAME (30 mg / Kg) foi injetado por via intraperitoneal 30 minutos antes da administração de Rut-bpy (100 mg / kg). A pressão arterial média (PAM) da aorta abdominal foi monitorada continuamente. RESULTADOS: A pressão arterial média (PAM) em ratos do grupo G3 subiu progressivamente, chegando a 147 ±16 mm Hg, em comparação com 100 ±19 mm Hg em ratos do G1 (p <0,05). Em ratos G4, tratados com L-NAME + Rut-bpy, a PAM atingiu 149±11 milímetros de Hg, enquanto no G2 (ratos tratados com Rut bpy) os valores da PAM foram 106 ±11 mm Hg. No G1 esses valores decresceram progressivamente, atingindo 87±14 mm Hg após 30 minutos. Um achado importante foi a manutenção da PAM durante todo o experimento em ratos do grupo G2. CONCLUSÃO: O uso de Rut bpy não diminui a PAM em ratos hipertensos por L-NAME. No entanto, quando ele é usado em ratos anestesiados, hipotensos, uma pressão arterial estável é obtida.

Synthesis, spectroscopic characterization, thermal investigation and antimicrobial activity of S, O and N-donor heterocyclic schiff base ligands and their Co[II], Cd[II], Hg[II], Fe[III] and UO[2][II] metal complexes

The polydentate ligands 2,5-N,N-bis [dimethy1-1-pheny1-4-pyrazoline-5-one] furanidine; 2,5-N,N-bis [pyridine]furanidine and 2,5-N, N-bis [2-thiophenol] furanidine [L[1]- L[3]], have been prepared and identified. The chemical behavior of these ligands towards some metal cations such as Co[II],Cd [II], Hg [II], Fe [III] and UO[2] [II] was studied. The isolated complexes are characterized using analytical data, IR, [1]H-NMR, UV-visible, mass spectroscopy, magnetic susceptibility, thermal analysis and molar conductance measurements. Bonding of the ligands with the metal ions is deducted from IR spectra and the presence of the mononuclear complexes are inferred from the mass spectral study. An octahedral structure is proposed for the prepared metal complexes and some ligand field parameters [D[q], B, and beta] in addition to LFSE were calculated from electronic spectral data. All synthesized compounds were screened for their antimicrobial activity against gram positive and gram negative bacteria and fungi. The biological evaluation study showed high to moderate bacterial activity compared with the ligands, their metal complexes and known antibiotics data

Effects of ternary complexes of copper with salicylaldehyde-amino acid Schiff base coordination compounds on the proliferation of BGC823 cells / 癌症

<p><b>BACKGROUND AND OBJECTIVE</b>The basic structure of salicylaldehyde-amino acid Schiff base compounds includes a C=N chemical bond. These compounds show significant antitumor activities in vitro when combined with a metal ion. This study investigated the effects and possible mechanisms of four salicylaldehyde-amino acid Schiff base copper ternary coordination compounds on the proliferation of human gastric cancer cell line BGC823.</p><p><b>METHODS</b>The BGC823 cells were treated with the four compounds (6B, 7B, 6P, and 7P). Cell proliferation was detected by MTT assay. Apoptosis and changes in the cell cycle were analyzed by flow cytometry. DNA damage was observed using a DNA ladder assay. The expression of p53 protein was determined by immunocytochemistry.</p><p><b>RESULTS</b>The proliferation of BGC823 cells was significantly inhibited by the four compounds and the effect was concentration-dependent. The half maximal inhibitory concentration (IC50) of 6B, 7B, 6P, and 7P for BGC823 cells were 18.10, 27.50, 3.61, and 3.45 micromol/L, respectively. Flow cytometry showed the four drugs induced apoptosis in BGC823 cells, which was confirmed by DNA ladder experiments. Flow cytometry also detected changed phases in the cell cycle from treatment with the compounds. The percent of cells in the G(0)/G(1) phase decreased and that of cells in the G1/S and G(2)/M phases increased, indicating that S-and G2-phase blockages exist. As shown by immunocytochemistry, the expression of p53 decreased in BGC823 cells treated with the four drugs, indicating the involvement of the p53 pathway to BGC823 cell apoptosis.</p><p><b>CONCLUSIONS</b>The four compounds showed significant activities on restraining proliferation of BGC823 cells in vitro, induced apoptosis, and caused changes in the cell cycle. This may be related to the downregulation of p53.</p>

In vivo Tracking of Mesenchymal Stem Cells Labeled with a Novel Chitosan-coated Superparamagnetic Iron Oxide Nanoparticles using 3.0T MRI

This study aimed to characterize and MRI track the mesenchymal stem cells labeled with chitosan-coated superparamagnetic iron oxide (Chitosan-SPIO). Chitosan-SPIO was synthesized from a mixture of FeCl2 and FeCl3. The human bone marrow derived mesenchymal stem cells (hBM-MSC) were labeled with 50 microg Fe/mL chitosan-SPIO and Resovist. The labeling efficiency was assessed by iron content, Prussian blue staining, electron microscopy and in vitro MR imaging. The labeled cells were also analyzed for cytotoxicity, phenotype and differentiation potential. Electron microscopic observations and Prussian blue staining revealed 100% of cells were labeled with iron particles. MR imaging was able to detect the labeled MSC successfully. Chitosan-SPIO did not show any cytotoxicity up to 200 microgram Fe/mL concentration. The labeled stem cells did not exhibit any significant alterations in the surface markers expression or adipo/osteo/chondrogenic differentiation potential when compared to unlabeled control cells. After contralateral injection into rabbit ischemic brain, the iron labeled stem cells were tracked by periodical in vivo MR images. The migration of cells was also confirmed by histological studies. The novel chitosan-SPIO enables to label and track MSC for in vivo MRI without cellular alteration.

Electrochemical, Antifungal, Antibacterial and DNA Cleavage Studies of Some Co(II), Ni(II), Cu(II) and Zn(II)-Copolymer Complexes

Cyclic voltammetric measurements were performed for Co(II), Ni(II), Cu(II) and Zn(II) complexes of 1 : 1 alternating copolymer, poly(3-nitrobenzylidene-1-naphthylamine-co-succinic anhydride) (L) and Ni(II) and Cu(II) complexes of 1 : 1 alternating copolymer, poly(3-nitrobenzylidene-1-naphthylamine-co-methacrylic acid) (L1). The in vitro biological screening effects of the investigated compounds were tested against the fungal species including Aspergillus niger, Rhizopus stolonifer, Aspergillus flavus, Rhizoctonia bataicola and Candida albicans and bacterial species including Staphylococcus aureus, Escherichia coli, Klebsiella pneumaniae, Proteus vulgaris and Pseudomonas aeruginosa by well diffusion method. A comparative study of inhibition values of the copolymers and their complexes indicates that the complexes exhibit higher antimicrobial activity. Copper ions are proven to be essential for the growth-inhibitor effect. The extent of inhibition appeared to be strongly dependent on the initial cell density and on the growth medium. The nuclease activity of the above metal complexes were assessed by gel electrophoresis assay and the results show that the copper complexes can cleave pUC18 DNA effectively in presence of hydrogen peroxide compared to other metal complexes. The degradation experiments using Rhodamine B dye indicate that the hydroxyl radical species are involved in the DNA cleavage reactions.

New pH-Metric method for determination of some angiotensin converting enzyme inhibitors through their complex formation with some transition metal ions

Study of mixed ligand complexes of Co[2+] and Zn[2+] with three Angiotensin converting enzyme inhibitors [ACE] was conducted in aqueous solution by pH metric titration. These are Enalapril maleate [I], Perindopril [II] and Moexipril [III] and one of the amino acid family [glycine]. Protonation constants of the three drugs and stability constants of the binary and ternary complexes were determined at [25 +/- 1] [degree sign] C and ionic strength 0.1M NaCl. The stability constants of the binary complexes of I, II and III with Co[2+] and Zn[2+] were performed and the results indicate the presence of one formation constant for the complexes of Co[2+] and Zn[2+] ions with II and III and two formation constants for I. By introducing glycine in the above binary complexes, ternary complexes were formed. The formation constant of the ternary complexes of I, II and III with Co[2+] and Zn[2+] ions with glycine was also calculated at the same temperature and ionic strength. This potentiometric technique was utilized also for the determination of the cited drugs

[The] biocidal activity of some phosphate cationic surfactant complexes

A series of oil soluble surface active agents based on triethanolamine hydrochloride and alkylated phosphoric acid was synthesized and characterized as surface active agents. Transition metal complex of Cu[ll], Co[Il] and Fe[Ill] was synthesized throughout direct complexation between the transition metal ions and the synthesized surfactants. The chemical structures of these compounds were confirmed using elemental analysis, FTIR and [1] H-NMR spectroscopy. The synthesized compounds were oil soluble and comprise good interfacial tension and emulsion stability towards oil-water systems. The biological activity of the synthesized surfactants and their metal complexes was applied as biocides for different types of bacteria and fungi. The biocidal activity of these compounds showed good activity towards the studied microorganisms. The experimental results of the surface and biocidal activities were greatly influenced by the nature of the transition metal ions, as well as the hydrophobic chain length. A comparison between the influence of the metal ion type and the alkyl chain length on their biological activity was done

Transition metal complexes with pyrazolone based ligand. thermogravimetric and spectroscopic studies

Transition metal complexes of Schiff base ligand [L] derived I from thiophene 2-carboxaldehyde and 4-aminoantipyrine have been synthesized to study possible structural determination for these complexes using spectroscopic and conductivity methods. Magnetic susceptibility measurements and thermal analysis were performed. Elemental analysis and conductometric titration showed the stoichiometry of the complexes. The molar conductivities of the complexes indicate that all complexes are non-electrolyte, except Ni[2+] complex behaves as 1:2 electrolyte and Zn[2+] complex is 1:1 electrolyte. Magnetic susceptibility measurements and electronic absorption spectra suggest tetrahedral geometry for CO[+2] chelate, The diamagnetic behaviour of Ni[2+] chelate indicates a square planer configuration, distorted octahedral structure for Cu[2+] chelate, Hg[2+] and Fe[3+] chelates have octahedral configuration and Zn[2+] chelate has square planar structure. Thermal studies indicate weight loss associated with water molecules. Some of the complexes show antibacterial and antifungal activities against four species of bacteria as well as four species of fungi and the results were compared with known antibiotics

New metal complexes of semicarbazones derived from para phenylene diamine of NOO/or NO donor sites and their antimicrobial screening

The synthesis and characterization of new Mn[II]. Co[II] Ni[II] and Cu[II] complexes with semicarbazone ligands derived from para phenylene diamine [where L[1] = Semicarbazide-4-yl-benzene-4 [2-hydroxybenzalde-hyde semicarbazone] [SBFIBS], L[2] = Betizene-1, 4-bis-[2-hydroxybenz-aldehyde semicarbazone-4yl] [BBHBS], L[3] = Semicarbazide-4yl-benzene-4 [2-hydroxyacetophen-one-semicarbazone] SBHAS and L[4] = Semicarbazide-4yl-benzene-4 [2-nitrobenzaldehyde semicarbazone] [SBNBS]] are reported. The ligands contain NOO/or NO donor sites. The elemental analysis suggests different stoichiometries 1: 2: 1 and 1: 2 [M: L]. IR spectra data indicate covalent bond through the oxygen atom of the hydroxyl group, coordination of the carbonyl oxygen and the azomethine nitrogen / or nitrogen of the amine group to the metal ion. TGA determined whether the water or solvent molecules are inside or outside the coordination sphere. Magnetic susceptibility and electronic data are in favour of octahedral structures except in the case of Co [II] complexes of ligand BBHBS and SBHAS as they favour the tetrahedral structure. The biological activity of the complexes has been tested. These complexes showed promising antifungal activities