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Zinc metal–organic frameworks have emerged as promising candidates, demonstrating excellent biological properties stemming from the unique characteristics of MOFs and zinc. In this study, we employed a facile method to synthesize a zinc metal–organic framework [Zn(IP)(H2O)] using ultrasound irradiation, with the linker being isophthalic acid (IPA) (1,3-benzene dicarboxylic acid). The parent Zn-MOF and two Ag/Zn-MOF samples prepared via loading and encapsulation methods were comprehensively characterized using various techniques, including FT-IR, XRD, SEM, TEM, N2 adsorption–desorption isotherm, UV–vis spectroscopy and TGA. The parent Zn-MOF and two Ag/Zn-MOF samples exhibited a broad spectrum of antibacterial effects. Remarkably, genomic DNA of P. aeruginosa was effectively degraded by Zn-MOF, further supporting its potent antibacterial results. The free radical inhibition assay demonstrated a 71.0% inhibition under the influence of Zn-MOF. In vitro cytotoxicity activity of Zn-MOF against HepG-2 and Caco-2 cell lines revealed differential cytotoxic effects, with higher cytotoxicity against Caco-2 as explored from the IC50 values. This cytotoxicity was supported by the high binding affinity of Zn-MOF to CT-DNA. Importantly, the non-toxic property of Zn-MOF was confirmed through its lack of cytotoxic effects against normal lung cell (Wi-38). The anti-inflammatory treatment of Zn-MOF achieved 75.0% efficiency relative to the standard Ibuprofen drug. DFT and docking provided insights into the geometric stability of Zn-MOF and its interaction with active amino acids within selected proteins associated with the investigated diseases. Finally, the synthesized Zn-MOF shows promise for applications in cancer treatment, chemoprevention, and particularly antibacterial purposes. [ABSTRACT FROM AUTHOR]

Oxovanadium (IV) and diphenyltin (IV) complexes were synthesized on the nanoscale based on the Schiff base (H2L) derived from salicylaldehyde and d‐glucosamine. The complexes were formed with a molar ratio of 1:1 and 1:2 (metal: dligand) relative to oxovanadium (IV) and diphenyltin (IV), respectively. Fourier‐transform infrared spectroscopy, 1H and 13C nuclear magnetic resonance, mass fragmentations, electronic transitions, thermogravimetric analysis, and density functional theory were employed to validate the structure of synthesized compounds. The results demonstrated that the ligand (H2L) was successfully attached to oxovanadium (IV) and diphenyltin (IV) as di‐anionic and mono‐anionic ligands, respectively. The size of the complexes was investigated using the transmission scanning microscope. The work presents a prospective concept for the drug design of the targeted anticancer through the glucose moiety. All compounds revealed remarkable anticancer activities against the colorectal (HCT‐116) cell line, recording IC50 values 4.94, 21.73, and 62.5 μg/ml for VO (II)(L), free H2L, and Sn (ph)2(HL)2, respectively. The IC50 value of VO (II)(L) complex was increased after the quercetin inhibitor. Therefore, the sugar‐conjugated compound can be recognized by the glucose recognition binding site of GLUT and their cell‐killing effect depends highly on the GLUT inhibitor, quercetin. The potential GLUT transportability of the compounds was investigated through a molecular docking study. The anti‐migration activity was investigated for VO (II)(L) complex. The free ligand observed the best antimicrobial results. The antibacterial stimulation was investigated and represented different interaction types with the selected ribosyl transferase enzyme. [ABSTRACT FROM AUTHOR]

The main objective of this study is to synthesize and characterize of a new three complexes of Pd (II), Cu (II), and Cu (I) metal ions with novel ligand ((Z)-2-(phenylamino)-N'-(thiophen-2-ylmethylene)acetohydrazide) H2LB. The structural composition of new compounds was assessed using several analytical techniques including FT-IR, ¹H-NMR, electronic spectra, powder Xray diffraction, and thermal behavior analysis. The Gaussian09 program employed the Density Functional Theory (DFT) approach to optimize the geometry of all synthesized compounds, therefore obtaining the most favorable structures and crucial parameters. An investigation was conducted to examine the impact of γ-irradiation on ligands and complexes. Before and after γ-irradiation, the antimicrobial efficiency was investigated for the activity of ligands and their chelates. The Cu(I) complex demonstrated enhanced antibacterial activity after irradiation, as well as other standard medications such as ampicillin and gentamicin. Similarly, the Cu(I) complex exhibited superior activity against antifungal species relative to the standard drug Nystatin. The docking investigation utilized the target location of the topoisomerase enzyme (2xct) chain A. [ABSTRACT FROM AUTHOR]

A new series of Co(II), Zn(II), Ru(III), and Ag(I) complexes with the ligand (Z)‐N′‐(1‐(thiophen‐2‐yl)ethylidene)‐2‐(p‐tolylamino)acetohydrazide (H2L) has been prepared. FT‐IR, 1H‐NMR, electronic spectra, powder X‐ray, and thermal behavior were applied to elucidate the structural composition of new compounds. The electronic spectra proved that the Co(II), Zn(II), and Ru(III) complexes possess tetrahedral geometry, except the Ag(I) complex is a binuclear complex. The mass spectrum of the Zn(II) and Ag(I) chelates and the molecular ion peak observed at m/z values equivalent to the calculated molecular weight confirmed the proposed structure. Also, the SEM scanning electron microscope technique explored the spherical shape of all chelates, and the nanoscale was confirmed through TEM; the transmission electron microscope tool that provided the 7.0 nm was achieved in the case of Zn(II) chelate. Geometry optimization for all synthesized compounds was estimated by density functional theory (DFT) method using the Gaussian09 program. Biological screening as an antimicrobial and antitumor was studied. The Ru(III) complex revealed the greatest antibacterial efficiency, followed by the Co(II) complex. Co(II) complex revealed a greater affinity against fungi such as Candida albicans and Aspergillus niger. All chelate‐induced antitumor effects against the MCF‐7 cell line, especially Ag(I) complex (IC50 = 62.36 μg/mL), exhibited the greatest efficiency. The activity sequence follows the order doxorubicin (standard drugs) > Ag(I) > Zn(II) > ligand < Ru(III) > Co(III) chelates. The molecular docking was performed and validated to support the biological results. [ABSTRACT FROM AUTHOR]

New complexes of molecular formulae of [Cu(H2L1)I] (B1), [Cu(H2L)2(ClO4)2](B2), [Zn (H2L)2(H2O)]SO4(B3) and [Cd(H2L)Cl]Cl(B4) of ligand N-phenyl-2-(p-tolylglycyl)hydrazine -1-carbothioamide (B) have been prepared and characterized by 1H-NMR, Mass spectra, FT-IR, elemental analyses, molar conductance, UV–visible spectra, magnetic susceptibility measurements, thermogravimetric analysis (TGA/DTG) and X-ray powder diffraction before and after irradiation. Elemental analyses indicate that the metal complexes have 1:1 (metal/ ligand) (B1 and B4) or 1:2 stoichiometry for complexes (B2 and B3). The results confirmed that gamma ray enhanced the stability of irradiated compounds as compared to non-irradiated compounds. XRD patterns proved that increasing the crystallinity of the samples and the particles is in nanosize range before and after gamma irradiation. These studies revealed that Cu(II) and Zn(II) complexes adopted octahedral geometry, and Cu(I) and Cd(II) complexes were found to be tetrahedral. The theoretical conformational structure analyses were performed using density functional theory for ligand and complexes at B3LYP functional with 6–31G basis set for ligand and LANL2DZ basis set for complexes. The ligand (B, A) and complexes (B1–B4) and (A1–A4) before and after irradiated have been tested for their inhibitory effect on the growth of bacteria against gram-positive (Streptococcus pyogenes) and gram-negative (Escherichia coli). Molecular docking investigation proved that the Zn(II) complex had interesting interactions with active site amino acids of topoisomerase II DNA gyrase enzymes (code: 2XCT). [ABSTRACT FROM AUTHOR]

Nano‐structure Cu(II) complex [Cu(AMAB)2]Cl2 with Schiff base (AMAB) derived from the condensation between 4‐(dimethylamino)benzaldehyde and amoxicillin trihydrate was prepared. (AMAB) Schiff base and its Cu(II) complex were identified and confirmed by different physicochemical techniques. The Schiff base (AMAB) was coordinated to copper ion through carbonyl oxygen and imine nitrogen donor sites. X‐ray powder diffraction shows a cubic crystal system of the Cu(II) complex. The density functional theory was used to optimize the structure geometries of the investigated compounds. The molecular docking of the active amino acids of the investigated proteins' interactions with the tested compounds was evaluated. The bactericidal or bacteriostatic effect of the compounds was screened against some bacterial strains. The activity of Cu‐chelate against Gram‐negative bacteria was mainly more effective than its (AMAB) ligand and vice versa in the case of Gram‐positive bacteria. The biological activity of the prepared compounds with biomolecules calf thymus DNA (CT‐DNA) was determined by electronic absorption spectra and DNA gel electrophoresis technique. All studies revealed that the Cu‐chelate derivative exhibited better binding affinity to both CT‐DNA than the AMAB and amoxicillin itself. The anti‐inflammatory effect of the designed compounds was determined by testing their protein denaturation inhibitory activity spectrophotometrically. All obtained data supported that the designed nano‐Cu(II) complex with Schiff base (AMAB) is a potent bactericide against H. pylori, and exhibits anti‐inflammatory activity. The dual inhibition effects of the designed compound represent a modern therapeutic approach with extended spectrum of action. Therefore, it can act as good drug target in antimicrobial and anti‐inflammtory therapies. Finally, H. pylori resistance to amoxicillin is absent or rare in many countries, thus amoxicillin nanoparticles may be beneficial for countries where amoxicillin resistance is reported. [ABSTRACT FROM AUTHOR]

The Schiff base (3‐APT) was a bidentate ligand produced from the condensation between 3‐acetylpyridine and the amine group of thiosemicarbazide. Metal chelates were successfully obtained with formulas [Cu(3‐APT)2X]X, [Ni(3‐APT)2]X2.H2O and [Pd(3‐APT)X2] (where 3‐APT = 3‐acetylpyridine thiosemicarbazone and X = Cl−). The characterization was performed by various physicochemical tools. The studied (3‐APT) ligand had two donor sites through both azomethine nitrogen and thiocarbonyl sulfur. The characterization tools observed the presence of two different geometric shapes. The square planar structure in the case of both nickel (II) and palladium (II) chelates and the square pyramidal structure in the case of copper (II) complex. The characterization involved a 1HNMR study for the (3‐APT) ligand and its square planar Pd (II) and Ni (II) chelates. The density functional theory was used to structurally optimize the synthesized ligand and its chelates. The antibacterial activity was evaluated using different types of bacteria showing superior results. The breast (MCF‐7) cell line was selected to investigate the cytotoxic effect of formed compounds. The palladium (II) complex was the most cytotoxic effective compound with the least IC50 value. Further theoretical molecular docking study was performed to observe the active sites in the selected proteins during their interactions with our compounds. [ABSTRACT FROM AUTHOR]

Ru(H2dtpa) (H2O) and Pd (DME)Cl2 were prepared, and their structures were confirmed by different structural tools. [Ru(H4dtpa) (cysteine)] Cl was separated as a model for the interaction of Ru (III) complex containing DTPA ligand with its corresponding most active amino acid and the geometrical parameters for the ternary complex and their constituent ligands are evaluated. Cytotoxicity was examined for both complexes against different cancer cell lines (HCT116, A549 and Mcf7). They were tested against a normal human lung cell line (W138). In addition, both complexes ensured cytocidal, not cytostatic effect. Several molecular tools were utilized in order to figure out the mechanism of action that two complexes followed to inhibit human colon cancer (HCT116) cell line. Gene expression analysis, cell cycle assay, genomic DNA analysis, and apoptosis were a molecular techniques that proved both Ru(H2dtpa) (H2O) and Pd (DME)Cl2 complexes were promising and effective chemotherapeutic agents against colon carcinoma in this current study. So, authors recommended more in vivo future studies should be done to make sure of complexes bioactivity and safety before they would be used commercially. [ABSTRACT FROM AUTHOR]

Pd (II) complex was prepared from the interaction with Schiff base based on the condensation amoxicillin trihydrate drug and 4‐N,N‐dimethylaminobenzaldehyde. The complex was prepared on the nanoscale that was investigated using transmission electron microscopy (TEM). The chemical structure of the synthesized Schiff base and its Pd (II) chelate was proved through several techniques. Assays using MTT and lactate dehydrogenase verified the Pd (II) complex ability to inhibit human prostate cancer cells (PC3). According to the findings, the inhibition of PC3 cell growth was directly proportional to the dose of Pd (II) complex. Its highest IC50 value was attained after 48 h of incubation reached to 22.6 μg/mL. As a measure of DNA damage in PC3 cells, this IC50 value demonstrated a significant increase in early and late apoptotic cells with an intense comet nucleus. Given that the concentration of reactive oxygen species (ROS) in treated PC3 cells was much higher than in control ones. These results contributed to the notion that ROS‐mediated cell death, which may have taken place via the mitochondrial pathway, was the mechanism by which the Pd (II) complex inhibited the proliferation of PC3 cancer cells. The prepared Pd (II) complex was fabricated and casted onto GC electrode for investigate the dopamine concentration in human serum. The limit of detection and limit of quantization were found to be 0.0127 and 0.0424 μM, respectively, which were in a good agreement with literature and were found to be an improvement to that present in the literature. [ABSTRACT FROM AUTHOR]

Four new complexes (Ni2+, Cu2+, Ag+, and Hg2+) were prepared from the ligand N-(4-chlorophenyl)-2-(phenylglycyl)hydrazine-1-carbothioamide (H2L). Analytical and spectroscopic techniques were used to clarify the structural composition of the new chelates. In addition, all chelates were tested against bacterial strains and the HepG2 cell line to determine their antiseptic and carcinogenic properties. The Ni(II) complex was preferable to the other chelates. Molecular optimization revealed that H2L had the highest reactivity, followed by Hg-chelate, Ag-chelate, Ni-chelate, and Cu-chelate. Moreover, molecular docking was investigated against two different proteins: the ribosyltransferase enzyme (code: 3GEY) and the EGFR tyrosine kinase receptor (code: 1m17). [ABSTRACT FROM AUTHOR]

The prevalence of obesity has increased the incidence of obesity-related coagulation disorders. The current study assessed the effectiveness of combined aerobic exercise and laser phototherapy on the coagulation profile and body measurements in older adults with obesity compared to aerobic exercise alone, which has not been adequately explored. We included 76 obese people (50% women and 50% men) with a mean age of 67.83 ± 4.84 years and a body mass index of 34.55 ± 2.67 kg/m2. The participants were randomly assigned to the experimental group (which received aerobic training with laser phototherapy) and the control group (which received aerobic training alone) for three months. From the baseline to the final analysis, the absolute changes in specific coagulation biomarker levels (fibrinogen, fibrin fragment D, prothrombin time, Kaolin-Cephalin Coagulation Time), and contributing parameters (C-reactive protein and total cholesterol), were assessed. In comparison to the control group, the experimental group showed significant improvements in all evaluated measures (p < 0.001). So, in comparison to aerobic exercise alone, combined aerobic exercise and laser phototherapy had superior positive effects on coagulation biomarkers and decreased the risk of thromboembolism throughout a three-month intervention period in senior obese persons. Therefore, we suggest adopting laser phototherapy for individuals with a greater risk of hypercoagulability. The research was entered into the database of clinical trials under the identification NCT04503317. [ABSTRACT FROM AUTHOR]

Multidrug resistant (MDR) Acinetobacter baumannii is a critical opportunistic pathogen in healthcare-associated infections (HAI). This is attributed to several factors, including its ability to develop biofilms that can enhance antimicrobial resistance (AMR) in addition to creating an environment for horizontal transfer of antibiotic resistance genes. The role of the efflux pump in biofilm formation is important for studies on alternative treatments for biofilms. One of the significant efflux pump families is the RND efflux pump family, which is common in Gram negative bacteria. The aim is to study the role of the RND efflux pump in biofilm formation by A. baumannii. The biofilm formation potential of thirty-four MDR A. baumannii isolates was evaluated by crystal violet assays. The effect of efflux pump inhibition and activation was studied using the efflux pump inhibitor carbonyl cyanide 3-chlorophenylhydrazone (CCCP) and the RND efflux pump substrate levofloxacin (at sub-MIC), respectively. The isolates were genotypically grouped by enterobacterial repetitive intergenic consensus (ERIC) typing and the expression of adeABC, adeFGH, and adeIJK efflux pump genes was measured by qPCR. Overall, 88.2% (30/34) of isolates were biofilm producers (the phenotype was variable including strong and weak producers). Efflux pump inhibition by CCCP reduced the biofilm formation significantly (p < 0.05) in 17.6% (6/34) of some isolates, whereas sub-MICs of the substrate levofloxacin increased biofilm formation in 20.5% (7/34) of other isolates. Overexpression of the three RND efflux pump genes was detected in five out of eleven selected isolates for qPCR with remarkable overexpression in the adeJ gene. No correlation was detected between the biofilm phenotype pattern and the RND efflux pump gene expression in biofilm cells relative to planktonic cells. In conclusion, the role of the RND efflux pumps AdeABC, AdeFGH, and AdeIJK in biofilm formation does not appear to be pivotal and the expression differs according to the genetic background of each strain. Thus, these pumps may not be a promising target for biofilm inhibition. [ABSTRACT FROM AUTHOR]

Novel Schiff base was synthesized from the condensation reaction of metformin with [4‐(Diethylamino) benzaldehyde (NBM). Different metal complexes were prepared using Pd (II), Pt (II), Cu (II), and V (IV) metal ions. All complexes showed the nonelectrolytic behavior. So, the expected molecular formulas for complexes were [Pd (NBM)Cl2], [Pt (NBM)Cl2], [Cu (NBM)2Cl2] and [VO (NBM)2]. The cytotoxicity of (NBM) Schiff base and its metal complexes on human cancer cell line, MCF‐7, was investigated. V (IV) and Cu (II) complexes showed potential blood glucose lowering effect higher than the commercial metformin drug. VO (II) complex has superior antioxidant activity more than the other synthesized compounds and the standard ascorbic acid. Molecular docking investigation proved the presence of interesting interactions between all synthesized compounds with the active site amino acids of EGFR tyrosine kinase (anticancer activity). The molecular docking of metal complexes has observed effective inhibition for the specific mTOR protein that is expected to aid the growth of the COVID‐19 virus. [ABSTRACT FROM AUTHOR]

Ni (II) and Co (II) complexes of thiosemicarbazide ligand (2‐(anilinoacetyl)‐N‐(3‐methylphenyl)hydrazine‐1‐carbothioamide(H2LB) have been prepared and characterized by 1HNMR, IR, elemental analyses, molar conductance, UV–visible spectra, magnetic susceptibility measurements, thermogravimetric analysis (TGA/DTG), and X‐ray differaction pattern before and after irradiation. The results confirmed that gamma rays enhanced the stability of irradiated compounds compared with those non‐irradiated. Density functional theory (DFT) calculations of synthesized compounds were completely optimized with respect to the energy using B3LYP level. DNA binding of compounds before and after gamma irradiation has been studied. Inhibitory effect on the growth of bacteria against gram‐positive (Streptococcus pyogenes) and gram‐negative (Escherichia coli) of synthesized compounds have been investigated. The results revealed that Ni (II) complex after gamma irradiation showed a higher antibacterial activity against gram positive and gram negative bacteria more than all investigated compounds. The ability of scavenging 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) free radical by our synthesized compounds was investigated on the basis of the determination of IC50 values. [ABSTRACT FROM AUTHOR]

A self-assembly Pd-Schiff base complex was synthesized and used as an electrochemical sensor in phosphate buffer solution, where it enhanced the electrocatalytic activity toward the paracetamol detection. The Schiff base {(HL) = (4-(((Z)-3-(hydroxyimino) butan-2-ylidene) amino)-1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one)} was selected to prepare Pd-based complexes due to its high antimicrobial activity. A linear calibration curve was constructed using GC/Pd-SB in paracetamol concentration range of 1–50 μM and its detection limit was calculated as 0.067 μM. The modified electrode, GC/Pd-SB, could successfully determine the paracetamol concentration in human blood serum and commercial drug tablets with high sensitivity. The prepared metal complex was characterized using techniques, namely, X-ray diffraction (XRD) and scanning electron microscope (SEM). In addition, electrochemical studies were performed using different electrochemical techniques like cyclic voltammetry (CV), linear sweep voltammetry (LSV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS). DFT calculations were used to estimate the equilibrium geometry, molecular orbital, ground-state properties, and interaction energy between paracetamol and palladium. [ABSTRACT FROM AUTHOR]

A new series of Zr(IV), V(IV), Ru(III), and Cd(II) complexes with the ligand N-((5-hydroxy-4-oxo-4H-pyran-3-yl)methylene)-2-(p-tolylamino)acetohydrazide (H2L) have been prepared. FT-IR, 1H-NMR, electronic spectra, powder X-ray, and thermal behavior methods were applied to elucidate the structural composition of new compounds. Geometry optimization for all synthesized compounds was conducted using the Gaussian09 program via the DFT method, to obtain optimal structures and essential parameters. Moreover, the antibacterial and antitumor activity of the ligand and its complexes were studied, where the Cd(II) complex acquires probably the best antibacterial activity followed by the Ru(III) complex towards bacterial species than others when using ampicillin and gentamicin were used as standard drugs. The complexes exhibited interestingly antitumor potential against the MCF-7 breast cancer cell line. The cytotoxicity of the new complexes has been arranged to follow the order: Ru(III) complex > Cd(II) complex > Zr(IV) complex > V(IV) complex > ligand. Molecular docking was performed on the active site of ribosyltransferase and obtained good results. Structure-based molecular docking is used to identify a potential therapeutic inhibitor for NUDT5. [ABSTRACT FROM AUTHOR]

The role of starch aerogel (St-AG) and carboxymethyl cellulose (CMC) as biolgical active compounds, when they subjected for complexation with metal ions, is assessed in this work. The complexation is carried out with palladium(II) and copper(II) ions, in solid state. Different tools of analysis are carried out to characterize and elucidate the structures of these complexes, namely: elemental analysis, IR, thermal analysis, magnetic measurement and molar conductance techniques. All synthesized complexes are formed with 1:2 (metal:ligand) stoichiometry except the case of aerogel starch 1:1 (Pd:starch). All isolated complexes show a satisfactory cytotoxic effect results against colon cancer cell lines HCT11. Additionally, these complexes are screened for their antibacterial activities against two types of Gram positive and negative bacteria. Molecular docking investigation confirmed the cytotoxicity and antibacterial results. Proton-ligands association constants and their complex formation constants with some bivalent metal ions, using potentiometric method show that the complexes formed in solution have a stoichiometry of 1:1 [metal:ligand]. The effects of metal ion, ionic radius, electronegativity and nature of ligand on the formation constants are discussed. The formation constants of the complexes with 3D transition metals followed the order Mn2+ < Co2+ < Ni2+ < Cu2+ > Zn2+. [ABSTRACT FROM AUTHOR]

Introduction: Acinetobacter baumannii is an opportunistic pathogen, which can acquire new resistance genes. Infections by carbapenem-resistant A. baumannii (CRAB) in cancer patients cause high mortality. Methods: CRAB isolates from cancer patients were screened for carbapenemase-encoding genes that belong to Ambler classes (A), (B), and (D), followed by genotypic characterization by enterobacterial-repetitive-Intergenic-consensus–polymerase chain reaction (ERIC–PCR) and multilocus-sequence-typing (MLST). Results: A total of 94.1% of CRAB isolates co-harbored more than one carbapenemase-encoding gene. The genes blaNDM, blaOXA-23-like, and blaKPC showed the highest prevalence, with rates of 23 (67.7%), 19 (55.9%), and 17 (50%), respectively. ERIC-PCR revealed 19 patterns (grouped into 9 clusters). MLST analysis identified different sequence types (STs) (ST-268, ST-195, ST-1114, and ST-1632) that belong to the highly resistant easily spreadable International clone II (IC II). Genotype diversity indicated the dissemination of carbapenem-hydrolyzing, β-lactamase-encoding genes among genetically unrelated isolates. We observed a high prevalence of metallo-β-lactamase (MBL)-encoding genes (including the highly-resistant blaNDM gene that is capable of horizontal gene transfer) and of isolates harboring multiple carbapenemase-encoding genes from different classes. Conclusion: The findings are alarming and call for measures to prevent and control the spread of MBL-encoding genes among bacteria causing infections in cancer patients and other immunocompromised patient populations. [ABSTRACT FROM AUTHOR]

New coordination compounds of some selected metal ions from the first and second transition metals series with a Schiff base were synthesized and characterized. The Schiff base is derived from 4‐Aminoantipyrine and 3‐(hydroxyimino) butan‐2‐one. The compounds were characterized by different analysis tools like; elemental analysis, mass spectra, Fourier transform infrared (FTIR) as well as electronic spectra, magnetic measurements, molar conductance and thermal analysis technique. All complexes were formed with 1:1 (metal: ligand) stoichiometry except Mn (II) where 1:2 (Mn: ligand) is formed. Schiff base ligand interacted as a tridentate ligand by using the nitrogen atoms of the imine and the oximato groups and the carbonyl oxygen atom as donor groups with all studied metal ions except copper (II) and manganese (II) where the carbonyl oxygen is not shared in the coordination. These complexes show various physicochemical properties. X‐ray powder diffraction shows different crystal systems; Cd (II) complex: hexagonal, Cu (II) complex: orthorhombic; and [Ni (II), Mn (II), Rh (III) & Pd (II)] complexes: monoclinic. All compounds showed potent cytotoxicity against the growth of human liver cancer cell lines. The square planar Pd (II) complex was more active than those of octahedral geometries of all other synthesized complexes. Cd (II) complex has the highest microbial growth inhibition than the rest of the prepared complexes. The docking active sites interactions were evaluated using the selected proteins EGFR tyrosine kinase and protein crystal structure of GlcN‐O‐P synthase. in vitro antioxidant assay revealed potent free radical scavenging activity of the three synthesized Cu (II), Pd (II) and Rh (III) complexes that exceeded the standard ascorbic acid. Pd (II) complex shows the most significant inhibition denaturation percent. [ABSTRACT FROM AUTHOR]

Set of amino acid conjugates with carboxymethyl cellulose (CMC) were synthesized as ligands for complexation with Pd(II) ions. In this respect, different side chain of amino acids (Methonine, Lycine, Leucine and Phenyl alanine) are reacted with CMC via condensation reaction in the absence of a solvent. The formed conjugates and their Pd(II) complexes are characterized by TGA, FTIR, elemental, magnetism, conductivity analyses of conjugates and their Pd(II) complexes, as well as their behavior as anti-cancer for colon cell and anti-oxidant are assessed. The data evidence the complexation of conjugate with Pd (II) ions occurs in molar ratio 2:1, through carboxylate groups and aliphatic ether included in the CMC. The formed complexes are diamagnetic and square planar geometry. The greatest inhibition in human tumor cell lines-HCT116 colon cancer cell proliferation is observed in the case of phenyl alanine (92.6%) and methionine (53.6%) conjugates at a dose of 100 µg/mL. The IC50 of these conjugates are 51.2 µg/mL and 90.3 µg/mL, respectively. Both Pd-free conjugates and their complexes have antioxidant property (IC50 ∼ 58–67%). The greatest anti-oxidant behavior is noticed for Lycine conjugate-Pd complex, this complex has anti-tumor activity that reaches 84% at a dose of 100 µg/mL. [ABSTRACT FROM AUTHOR]

Palladium (II) complexes of coumarinyl thiosemicarbazone derivatives as 1-(1-(2-oxo-2H-chromen-3-yl) ethylidene) thiosemicarbazone (OCETh), 1-(1-(6-bromo-2-oxo-2H-chromen-3-yl) ethylidene) thiosemicarbazone (BOCETh) and 1-(1-(3-oxo-3H-benzo[f]chromen-2-yl)ethylidene) thiosemicarbazone (NOCETh) were prepared. The complexes have the formula [Pd (L) Cl]. DMF, where DMF = dimethylformamide and L = OCETh, BOCETh or NOCETh. The studied ligands act as a tridentate ligand by using azomethine nitrogen, carbonyl oxygen and thiol sulfur as a monoanion center of donation. The characterization part was carried out using different physicochemical tools such as elemental analysis, IR, UV-visible, mass, magnetic measurement and molar conductance techniques. The theoretical conformational structure analyses were performed using density functional theory for ligands and complexes at B3LYP functional with 6-31 ++G(d,p) basis set for ligands and LANL2DZ basis set for complexes. The charge distribution within the ligands and its pd(II) complexes was calculated using Mulliken population analysis of (MPA) and natural population analysis (NPA). The prepared pd(II) complexes showed a satisfactory cytotoxic effect results against the human colon cancer cell line (HCT-116). Additionally, docking study was performed on colon cancer target cyclin-dependent kinase-2 to understand the cytotoxic modes of actions by the active compounds. The antibacterial activity was tested against some types of Gram-positive and negative bacteria. Molecular docking investigation proved that all synthesized compounds had interesting interactions with the active site amino acids of glucosamine-6-phosphate synthase. Density functional theory was used to theoretically analyze the conformational structure of the ligands and Pd (II) complexes. [ABSTRACT FROM AUTHOR]

Coumarinyl thiosemicarbazone derivatives (1E)‐1‐(1‐(2‐oxo‐2H‐chromen‐3‐yl)ethylidene)thiosemicarbazide (OCET), (1E)‐1‐(1‐(6‐bromo‐2‐ oxo‐2H‐chromen‐3‐yl)ethylidene)thiosemicarbazide (BOCET) and 1‐(1‐(3‐oxo‐3H‐benzo[f]chromen‐2‐yl)ethylidene)thiosemicarbazide (NOCET) and their Rh(III) complexes were synthesized, the characterization was carried out by elemental analysis, IR, UV–Visible, mass, magnetic measurement and molar conductance techniques. Data interpretation of the Rh(III) complexes indicates that the ligands of coumarinyl thiosemicarbazone derivatives were formed in stoichiometric ratios as 1:2 (metal: ligand). The studied ligands act as a bidentate ligand by using both azomethine nitrogen and thiol sulphur as monoanion center of donation. The theoretical conformational structure analyses were performed using density functional theory for ligands and complexes at B3LYP functional with 6‐31G(++)d,p basis set for ligands and LANL2DZ basis set for complexes. The charge distribution within the ligands and its Rh(III) complexes was calculated using Mulliken population analysis of (MPA) and natural population analysis (NPA). The antibacterial activity of the prepared compounds was tested against some types of Gram positive and negative bacteria. Molecular docking investigation proved that, the ligands and complexes had interesting interactions with active site amino acids of ribosyltransferase (code: 3GEY). [ABSTRACT FROM AUTHOR]

Proton-ligand association constants of 1-benzoyl(1,2,4-triazol-3-yl)thiourea (BTTU) and its complex formation constants with some bivalent metal ions Ni(II), Co(II), Mn(II), Zn(II), and Cu(II), have been determined potentiometrically in 50% EtOH–H2O and 0.1 M NaNO3. The complexes formed in solution have a stoichiometry of 1:1 and 1:2 [M:L], where M represents the metal ion and L the BTTU ligand. The corresponding thermodynamic parameters are derived and discussed. The complexes are stabilized by enthalpy changes and the results suggest that complexation is an enthalpy-driven process. The effects of metal ion, ionic radius, electronegativity, and nature of ligand on the formation constants are discussed. The formation constants of the complexes with 3d transition metals follow the order Mn2+ < Co2+ < Ni2+ < Cu2+ > Zn2+. The metal complexes were synthesized and characterized by elemental analyses, conductance, IR,1H NMR, and magnetic measurements. The low magnetic moment of 0.11 BM for the Cu(II) complex is suggestive of dimerization through Cu–Cu interaction. The concentration distribution diagrams of the complexes were evaluated. The ligands and their metal complexes have been screenedin vitroagainst some bacteria and fungi. [ABSTRACT FROM AUTHOR]

Pd(DME)Cl2 complex was synthesized and characterized, where DME is 2-{[2-(dimethylamino)ethyl]-methylamino}ethanol. Stoichiometry and stability constants of the complexes formed between various biologically relevant ligands (amino acids, peptides, DNA constituents, and dicarboxylic acids) and [Pd(DME)(H2O)2]2+ are investigated at 25°C and at constant 0.1 M ionic strength. The effect of dielectric constant of the medium on the stability constant of Pd(DME)-CBDCA complex, where CBDCA is cyclobutanedicarboxylate, is also reported. The concentration distribution diagrams of the various species formed are evaluated. The kinetics of base hydrolysis of amino acid esters coordinated to Pd(DME)2+ complex is investigated. The effect of the temperature on the kinetics of base hydrolysis of glycine methyl ester complex is studied. © 2010 Wiley Periodicals, Inc. Int J Chem Kinet 42: 608–618, 2010 [ABSTRACT FROM AUTHOR]

New Pb(II), Mn(II), Hg(II), and Zn(II) complexes, derived from 4-(4-chlorophenyl)-1-(2-(phenylamino)acetyl)thiosemicarbazone, were synthesized. The compounds with general formulas, [Pb(H2L)2(OAc)2]ETOH.H2O, [Mn(H2L)(HL)]Cl, [Hg2(H2L)(OH)SO4], and [Zn(H2L)(HL)]Cl, were characterized by physicochemical and theoretical studies. X-ray diffraction studies showed a decrease in the crystalline size of compounds that were exposed to gamma irradiation (γ-irradiation). Thermal studies of the synthesized complexes showed thermal stability of the Mn(II) and Pb(II) complexes after γ-irradiation compared to those before γ–irradiation, while no changes in the Zn(II) and Hg(II) complexes were observed. The optimized geometric structures of the ligand and metal complexes are discussed regarding density functional theory calculations (DFT). The antimicrobial activities of the ligand and metal complexes against several bacterial and fungal stains were screened before and after irradiation. The Hg(II) complex has shown excellent antibacterial activity before and after γ-irradiation. In vitro cytotoxicity screening of the ligand and the Mn(II) and Zn(II) complexes before and after γ-irradiation disclosed that both the ligand and Mn(II) complex exhibited higher activity against human liver (Hep-G2) than Zn(II). Molecular docking was performed on the active site of MK-2 and showed good results. [ABSTRACT FROM AUTHOR]

Nano structure metal complexes of Eu (III) and La (III) with two different nitrogen donor tridentate ligands: N‐(2‐Aminoethyl)‐1,3‐propanediamine "AEPD = L1" and 1‐(2‐Aminoethyl)piperazine "AEPz = L2", were prepared. All synthesized compounds were identified and confirmed by elemental analyses, molar conductivity and spectral analyses (UV–Visible, IR and mass). Conductance measurement indicates that all the complexes are non‐electrolytic in nature and the complexes were isolated in 1:1 molar ratio (metal: ligand). Thermal decomposition profiles were consistent with the proposed formulations. The ligands behave as a tridentate ligand through three nitrogen centers of donation. The nano‐size was investigated by using transmission electron microscopy (TEM). The geometric structure properties were analyzed using density functional theory (DFT) for ligands and their Lanthanum (III) complexes. The complexes were screened against some bacteria strains, hepatocellular cell line and diphenylhydrazine free radical. The molecular docking active sites interactions were evaluated. [ABSTRACT FROM AUTHOR]

This paper discuss the preparation of the binary system of Phosphate Based Glass (PBG) xP2O5–(100 − x) Na2O mol% and investigates the compositions that form glassy matrix. It is found that x in the range between x = 40–60 mol% and divided in to 5 glass samples (x = 40, 45, 50, 55, 60) and for compositions of 40 > x > 60 no glassy matrix is formed. The intensities of the peak centers of the IR spectra of sodium phosphate glasses and the suggested vibrational modes of structural phosphate chains, terminal groups and tabulated data imply a shift in absorption bands with increasing the Na2O mol% content. The amount of bridging phosphorous, shows a maximum value for the glass containing 60 mol% Na2O due to the depolymerization of the phosphate matrix with increasing Na2O content from 40 to 60 mol% via a breakdown of some terminal bonds (P=O) in the glass network which decreases the bond strength, consequently the peak center is shifted towards lower wave number. Essentially, five compositions of glassy samples were investigated: (x = 40, 45, 50, 55, and 60) mol%. The kinetics of dissolution rate were investigated by two ways: 1—the weight loss data and 2—electrical properties of the solution (pH, Electrical Conductivity) leached by the glass sample in to the deionized water. It is found that with increasing the Na2O% content, the pH values, the dissolution rate and the solubility are increasing. It could be noticed that the ionic levels increased with the immersion time and were directly related to the solubility of the glasses. The highest in solubility (x = 40) is the highest in EC and pH values caused by high Na2O%. By studying the effect of PBG on the real water medium physical characteristics the following results were achieved: Softening of (Treated drinking water, Nile raw water) by removal of hardness (Ca, Mg) by x = 50; 50% P2O5–50% Na2O, Sequestering and agglomerating of (groundwater, wastewater) of some heavy metals as (Fe, Mn) up to 100% removal by x = 60; 60% P2O5–40% Na2O and the electrical properties (pH, EC) were discussed. Results are assuring the possibility of applying PBG for groundwater treatment of high Fe and Mn content. The data show that municipal groundwater supplies become acceptable according to the guidelines of American Chemistry Council for safe drinking water by using of polyphosphates for water treatment. [ABSTRACT FROM AUTHOR]

The interaction of 3,3-bis(1-methylimidazol-2-yl)propionate (BIMP) with dimethyltin(IV) dichloride (DMT), dibutyltin(IV) dichloride (DBT), and diphenyltin(IV) dichloride (DPT) is investigated at 25°C and 0.1 M ionic strength in water for dimethyltin(IV), and in a 50% dioxane-water mixture for dibutyltin(IV) and diphenyltin(IV). The stepwise formation constants of the 1 : 1 and 1 : 2 complexes formed in solution are calculated from potentiometric measurements using the nonlinear least-square program MINIQUAD-75. The concentration distribution of the various complex species is evaluated as a function of pH. Displacement reactions of the coordinated 3,3-bis(1-methylimidazol-2-yl)propionate by inosine and inosine-5'-monophosphate are investigated from calculations based upon equilibrium properties. [ABSTRACT FROM AUTHOR]