Octahedral Geometry Research Articles

Synthesis, Antimicrobial, DNA Interactions, In Vitro Cytotoxicity, and Cell Cycle Analysis Efficiency of Newly Nano‐Sized Cu (II), Ni (II), Co (II), and Zn (II) Thio‐Schiff Base Complexes of 2‐((E)‐((4,5‐Dimethyl‐2‐(((E)‐4‐Methylbenzylidene)Amino)Phenyl)imino)Methyl)‐Benzenethiol

ABSTRACTNano‐sized bivalent metal complexes, specifically [M(L)2] with L = 2‐((E)‐((4,5‐dimethyl‐2‐(((E)‐4‐methylbenzylidene)amino)phenyl)‐imino)methyl)benzenethiol] (C23H22N2S) and M = Cu (II) (C1), Co (II) (C2), Ni (II) (C3), and Zn (II) (C4), underwent synthesis and subsequent characterization. Elemental analyses, infrared, NMR, mass, electronic, magnetic susceptibility, conductivity assessments, and X‐ray diffraction studies were used to assess our bivalent metal complexes. DFT studies were used to study the tautomeric equilibrium of the tridentate thio‐Schiff base ligand (HL), via the DFT\B3LYP method in connection with a 6–311G* correlation consistent basis set. Two tautomers, which are thione and thiol forms, were studied to estimate the predominant one. The metal formed four coordinated with the tridentate N2S donor thio‐Schiff base to form octahedral geometry complexes. The SEM, TEM, XRD, AFM, and EDX of the studied complexes unveiled distinct and strong diffraction peaks, signifying their crystalline nature and providing evidence of their particle sizes being within the nano‐size. The crystal sizes calculated for all complexes were determined to be ranging from 27.73 to 76.39 nm. The interactions between metal complexes and calf thymus DNA, and their potential for mimicking insulin activity, were investigated in a controlled lab setting by measuring their ability to inhibit alpha‐amylase. The antimicrobial potential of thio‐Schiff base ligand (HL) plus complexes (C1–C4) were tested. The viscosity and UV–Vis absorption determinations were utilized to assess the calf thymus DNA (CT‐DNA) interaction with the nano‐sized metal (II) chelates. Our flow cytometry data indicate significant levels of apoptosis and cell cycle arresting in both liver and breast cancer cell lines.

Synthesis, Characterization and Antimicrobial Analysis of Nickel and Cobalt Complexes of Condensates of Salicylaldehyde and 2-Hydroxy Aniline

This study on the synthesis, characterization and antimicrobial analysis of Nickel and Cobalt complexes of condensates of salicylaldehyde and 2-hydroxy aniline constitutes an attempt towards the development of new molecular compounds that could destroy the barrier of resistance of pharmaceutical products. The ligands of 2-phenyliminomethylphenol (PMP) and 2,2-hydroxy benzylidene aminophenol (HAP) were first prepared by separately reacting Aniline with Salicylaldehyde on the one hand, and 2-aminophenol with Salicylaldehyde on the other hand. The unmixed metal complexes were prepared by reacting either of 0.29 mmol 2-phenylimino methyl phenol ligand with the metal salt or 0.29 mmol 2,2-hydroxybenzylideneaminophenol ligand with the metal salt while the mixed metal complexes were prepared by addition of equimolar amount of ligands of 2-phenyliminomethylphenol and 2,2-hydroxybenzylideneaminophenol into the metal salt. The molecular structures of the ligands and their complexes have been determined and characterized using GC-MS, FTIR, UV-Vis, 1H-NMR, and X-ray diffraction techniques. The melting point and solubility of the ligands and synthesized complexes were equally determined. Antimicrobial studies were carried out with ligands PMP and HAP and the metal complexes using clinical isolates of Gram Positive Bacteria (Staphylococcus aureus and Bacillus substilis), Gram Negative Bacteria (Escherichia coli and Pseudomonas aeruginosa) and Fungi (Candida albicans and Aspergillus niger). All complexes and ligands were found to be soluble in dimethylsulfoxide (DMSO). Asymmetric Octahedral geometry is observed for Nickel (II) and Cobalt (II) complexes with PMP, HAP, and the mixed ligands. A bidentate ligand is coordinated to metal ions through oxygen atoms of carbonyl groups and nitrogen atoms of two imine groups for Nickel (II) and Cobalt (II) complexes. The findings from the XRD pattern indicate that the ligand and metal complexes are crystalline with a high crystallite size of 119.23nm to 638.67nm. The FTIR spectra for 2-phenyliminomethylphenol (PMP) showed IR absorption band at 1569.2 cm-1 suggesting the stretching vibration of the C=C bond in the benzene rings, while the bands at 1613.9 cm-1 indicated the =C-N stretching in the benzene ring. The complexes showed electronic spectra which suggest that energy was absorbed in the ultraviolet/visible region, producing changes in the electronic energy of the compound and resulting from the transition of valence electrons in the complexes. The XRD findings reveal that the crystal formed by the ligands and their respective complexes are large. The ligands were found to be larger in size than the complexes and this could be due to the complexation reactions. The X-ray diffractograms of the metal complexes produced good intense peaks that suggest high crystallinity. The ligand of 2-phenyliminomethylphenol (PMP) and 2,2-hydroxy benzylidene aminophenol (HAP) showed partial inhibitory action on the clinical isolates of Gram Postive, Gram Negative and zero inhibitory effect on the fungi while the divalent metal complexes of both mixed and unmixed ligands exhibited either stronger or strongest inhibition. The study concludes that the synthesized ligands and their metal complexes are purely crystalline as revealed by the chemical analysis, exhibited inhibitory actions on Gram Positive, Gram Negative and fungi species.

Characterization and Cytotoxic Assessment of Bis(2-hydroxy-3-carboxyphenyl)methane and Its Nickel(II) Complex.

A condensation reaction of salicylic acid with formaldehyde in the presence of sulfuric acid led to the synthesization of the bis(2-hydroxy-3-carboxyphenyl)methane (BHCM) ligand, which was subsequently allowed to bind with nickel (II) ions. In light of the information obtained from the elemental analyses (C, H, and M), spectral (IR, MS, 1H-NMR, and UV-Vis) and thermal and magnetic measurements, the most likely structures of the ligand and complex have been identified. It has been suggested that the BHCM coordinates in a tetradentate manner with two Ni(II) ions to produce an octahedral binuclear complex. The SEM and TEM morphology of the compounds showed spherical shapes. An X-ray diffraction analysis indicated a considerable difference in the diffraction patterns between BHCM (crystalline) and Ni-BHCM (amorphous), and the Scherrer equation was used to calculate the crystallite size. Some optical characteristics were estimated from UV-Vis spectra. The ligand and its nickel(II) complex underlie the range of semiconductors. It was verified that for human lung (A-549) cancer, the BHCM compound displayed a significant barrier to the proliferation test in noncancerous cells (human lung fibroblasts, WI-38), which was also undertaken. To demonstrate the binding affinities of the chosen compounds (BHCM and Ni-BHCM) in the receptor protein's active site [PDB ID: 5CAO], a molecular docking (MD) study was carried out.

Nonoxidovanadium(IV) Complex-Catalyzed Synthesis of 2-Amino-3-cyano-4H-pyrans/4H-chromenes, Biscoumarins, and Xanthenes under Green Conditions.

Reaction of [VIVO(acac)2] (Hacac = acetylacetone) with a Mannich base, N,N,N',N'-tetrakis(2-hydroxy-3,5-di-tert-butyl benzyl)-1,2-diaminoethane (H4L, I) in a 1:1 molar ratio in MeOH, leads to the formation of the nonoxidovanadium(IV) complex [VIVL] (1). Air stable complex 1 has been characterized using various spectroscopic techniques, DFT calculations, and single-crystal X-ray studies. 1 adopts distorted octahedral geometry where ligand coordinates through all coordination functionalities available. This complex has been used as a catalyst in the one-pot, three-component synthesis of 2-amino-3-cyano-4H-pyrans using 1,3-dicarbonyls (1,3-cyclohexanedione, dimedone, barbituric acid, and 4-hydroxycoumarin), malononitrile, and various substituted aromatic aldehydes in equimolar amounts employing ethanol as a green solvent. The catalytic reaction revealed that the multicomponent synthesis of 4H-pyrans and chromenes is greatly influenced by both types of 1,3-dicarbonyl compound employed and the nature of the substituent on the aromatic ring of the aldehyde. Synthesized catalyst has also been used in the synthesis of pharmacologically relevant oxygen-containing heterocycles, specifically, 1,8-dioxo-octahydro-1H-xanthenes and biscoumarins. The possible mechanism for the synthesized one-pot, multicomponent product has been proposed by isolating intermediate(s) generated during synthesis.

Crystal chemical investigations on TiU8S17 and U36Lu21S93I3 - ordered and disordered multinary uranium sulfides

The crystal chemistry of uranium sulfides is characterized by a large diversity in composition, crystal structures, oxidation states and physical properties. This holds also for TiU8S17 and U36Lu21S93I3, of which large single crystals up to several mm in length were grown by chemical vapor transport using iodine as a transport agent. TiU8S17 crystallizes with the monoclinic CrU8S17 structure type (C2/m, a = 13.3477(2) Å, b = 8.4927(2) Å, c = 10.4836(2) Å, β = 101.207(2)°) featuring distorted octahedra [TiS6] and bicapped trigonal prisms [US8]. Interatomic distances and X-ray photoelectron spectra indicate tetravalent uranium. Disordered U36Lu21S93I3 represents a new structure type (R3¯m, 13.3841(2) Å, 20.6447(2) Å) with an average crystal structure exhibiting square antiprisms [LuS8], bi- and tricapped trigonal prisms [US8] and [US9] and distorted octahedra [IU6]. Lutetium and sulfur atoms are disordered similar to Ce53Fe12S90X3, La53Fe12S90X3 (X = Cl, Br, I) and La52Fe12S90. This might be caused by positional shifts of iodine atoms away from the center of the polyhedron, thus avoiding unusually long U–I distances and severely disrupting the order of neighboring lutetium and sulfur atoms. The results of chemical analyses (ICP-MS, EDX), electron microscopy (TEM) and X-ray photoelectron spectroscopy support the composition and crystal structure of U36Lu21S93I3 and indicate mixed valency of uranium and charge balance according to the crystal chemical formula (U+III)18(U+IV)18(Lu+III)21(S-II)93(I–I)3.

Heterocyclic Schiff Base Complexes of Bivalent Transition Metals: Microwave-Assisted Green Synthesis, Structure Elucidation and Antimicrobial Studies

A heterocyclic Schiff base ligand [LH] namely {5‐[(E)‐[(1H‐pyrrol‐2‐yl)methylidene]amino]‐ 1,3,4‐thiadiazole‐2‐thiol}(NNN donor) and its divalent transition metals (Co2+, Ni2+, Cu2+ and Zn2+) mononuclear complexes were synthesised efficiently in relatively very short times (from one-two hours to 6-15 minutes) with higher yields [from 59% (conventional method) to 90% (green method)] by microwave-assisted greener process is presented here. The ligand and its complexes were characterised by elemental analysis, molar conductance, and magnetic susceptibility measurements and spectroscopic (IR, electronic, and NMR) analyses. All investigated complexes were found to be six coordinated ML2 [1:2 (metal: Ligand) ratio] type which possessed mononuclear octahedral geometry. The ligand and its metal complexes were screened for antimicrobial activity by the disc diffusion method, and the results indicate that the metal complexes are better antimicrobial agents compared to the Schiff base and the metal complexes have followed antimicrobial trends: Cu(II) complex > Co(II) complex > Ni(II) complex > Zn(II) complex > Schiff base

2D coordination polymers of cadmium(II) and zinc(II) derived from N,N'-bis(glycinyl)pyromellitic diimide: microwave-assisted synthesis, structures, spectroscopic properties and influence of metal-ion size.

Two new two-dimensional (2D) coordination polymers (CPs), namely, poly[diaqua[μ4-2,2'-(1,3,5,7-tetraoxo-1,2,3,5,6,7-hexahydropyrrolo[3,4-f]isoindole-2,6-diyl)diacetato-κ4O:O':O'':O''']cadmium(II)], [Cd(C14H6N2O8)(H2O)2]n (1), and poly[[tetraaqua[μ4-2,2'-(1,3,5,7-tetraoxo-1,2,3,5,6,7-hexahydropyrrolo[3,4-f]isoindole-2,6-diyl)diacetato-κ4O:O':O'':O'''][μ2-2,2'-(1,3,5,7-tetraoxo-1,2,3,5,6,7-hexahydropyrrolo[3,4-f]isoindole-2,6-diyl)diacetato-κ2O:O']dizinc(II)] dihydrate], {[Zn(C14H6N2O8(H2O)2]·H2O}n (2), have been synthesized by the microwave-irradiated reaction of Cd(CH3COO)2·2H2O and Zn(CH3COO)2·2H2O, respectively, with N,N'-bis(glycinyl)pyromellitic diimide {BGPD, namely, 2,2'-(1,3,5,7-tetraoxo-1,2,3,5,6,7-hexahydropyrrolo[3,4-f]isoindole-2,6-diyl)diacetic acid, H2L}. In the crystal structure of 1, the CdII ion is six-coordinated by four carboxylate O atoms from four symmetry-related L2- dianions and two coordinated water molecules, furnishing an octahedral coordination geometry. The bridging L2- dianion links four symmetry-related CdII cations into a 2D layer-like structure with a 3,4-connected bex topology. In the crystal structure of 2, the ZnII ion is five-coordinated by three carboxylate O atoms from three different L2- dianions and two coordination water molecules, furnishing a trigonal bipyramidal coordination geometry. Two crystallographically independent ligands serve as μ4- and μ2-bridges, respectively, to connect the ZnII ions, thereby forming a 2D layer with a 3,3-connected hcb topology. Crystal structure analysis reveals the presence of n→π* interactions between two carbonyl groups of the pyromellitic diimide moieties in 1 and 2. CP 1 exhibits an enhanced fluorescence emission compared with free H2L. The framework of 2 decomposes from 720 K, indicating its high thermal stability. A comparative analysis of a series of structures based on the BGPD ligand indicates that the metal-ion size has a great influence on the connection modes of the metal ions due to different steric effects, which, in turn, affects the structures of the SBUs (secondary building units) and frameworks.

Studies on a novel oxo-vanadium(V) complex of a tridentate ONO Schiff base ligand: Synthesis, characterization, X-ray crystal structure, Hirshfeld surface analysis, biological and catalytic activity

This study reports the successful synthesis and characterization of a novel oxovanadium(V) complex, [VO(L)(MeOH)(MeO)], prepared from 2-hydroxy-3-methoxybenzaldehyde and 2-methyl-3-aminoquinazoline. To elucidate the structure of the complex, we employed comprehensive characterization techniques such as CHN analysis, molar conductivity measurements, FT-IR, 1H NMR, UV-Vis spectroscopy, and single-crystal X-ray diffraction. The X-ray analysis confirmed an octahedral geometry around the V(V) center, coordinated with donor atoms from the deprotonated Schiff base ligand, an oxido group, a methanol molecule, and a methoxy group. Hirshfeld surface analysis was employed to evaluate intermolecular interactions.Furthermore, the complex exhibited impressively efficient catalytic activity in glucose oxidation under mild conditions (aqueous solution, room temperature, O2 oxidant), achieving a conversion rate of 98 %. Additionally, the antibacterial activity of the ligand and complex against various bacterial strains, including Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus cereus, was evaluated. The results demonstrated promising antibacterial potential of the [VO(L)(MeOH)(MeO)] complex, particularly against E. coli, P. aeruginosa, and B. cereus. These findings suggest potential applications of this new oxovanadium(V) complex in both catalysis and antibacterial treatments.

Exploring the Frontiers of Heterometallic Systems: the {FeW5} Octahedral Cluster Complex.

This research presents the first examples of heterometallic octahedral cluster complexes incorporating both 5d and 3d metals, specifically, tungsten and iron. The key compound, (TBA)2[FeW5Br14] (TBA = tetrabutylammonium), exhibits selective ligand substitution reactions at the iron site when exposed to various solvents. Several {FeW5}-type anions, namely, [FeW5Br14]2-, [FeW5Br13(L)]- (L = H2O, DMSO, CH3CN), and [(FeW5Br13)2O]4-, were revealed and characterized by single-crystal X-ray diffraction analysis. The redox properties of [FeW5Br14]2- were studied and compared with those of [W6Br14]2-. Density functional theory calculations demonstrated that the bonding between Fe and W atoms is fundamentally different from the bonding between 4d (Mo-Mo) or 5d (W-W) metals in isotypic {M6} clusters.

Synthesis, calf-thymus DNA interaction with trimethyl-/triphenyl-tin(IV) derivatives of ɑ-lipoic acid and their mixed ligand complexes with N-donor (1,10-phenanthroline/2,2′-bipyridyl/benzimidazole)

The mixed ligand complexes of trimethyl-/triphenyl-tin(IV) derivatives of ɑ-lipoic acid (HLA), viz. R3Sn(LA) {R = Me (1), and Ph (2)}with 1,10-phenanthroline (phen), viz. [Me3Sn(LA).phen] (3), 2,2′-bipyridyl, viz. [Ph3Sn(LA).by] (4) and benzimidazole (bz), viz. [R3Sn(LA).bz] {R = Me (5), and Ph (6)} were synthesised and satisfactorily characterized by analytical and spectroscopic techniques, especially FT-IR, NMR (1H, 13C, and 119Sn NMR) spectroscopy and ESI-MS spectrometry. The ∠C-Sn-C bond angle calculated by optimization of their gas-phase geometry revealed that complexes (1) and (2) have distorted tetrahedral geometry and complexes (3) and (4) exhibited distorted octahedral geometry while complexes (5) and (6) exhibited trigonal bipyramidal environment around the tin, which agreed with the data obtained from NMR. Spectroscopic titrations (UV–visible absorption, fluorescence titration, and circular dichroism) were performed to ascertain the binding mode of the complex with calf thymus DNA (CT-DNA). The obtained values of Kb in the order of 105 M−1 suggested partial intercalative interactions of complexes with DNA grooves/base pairs. The complexes efficiently cleaved plasmid DNA (pBR322) into supercoiled (Form I), nicked/circular (From II), and linear structure (Form III). The fascinating biophysical data suggests the potential of these complexes as anticancer agents.

Synthesis, structural characterization, molecular docking analysis and Carbonic Anhydrase IX inhibitory evaluations of novel Cerium(III)-based MOF constructed from 1,10-phenanthroline and fumaric acid.

In this study, a novel Cerium-based MOFs with 1,10-phenanthroline (phen) and fumaric acid (H2fum) has been hydrothermally synthesized as single crystal structurally characterized by X-ray diffraction, IR spectroscopy and ATG measurements. This compound corresponds to the formula: [Ce2(phen)2(fum)3(H2O)2]n(I), it crystallizes in the triclinic system with space group P1¯, with the following parameters: a = 9.062(1) Å, b = 10.0608(5) Å, c = 10.603(1) Å, α = 72.545(6) °, β = 77.57(1) °, γ = 69.959(6) °, V = 859.49(14) Å3, Z = 2.The structure revealed 2D bridged polymeric chains where the adjacent Ce(III) atoms are bridged by fumarate linkers with a mean intermetallic distance of about 9.36 Å. H···O bonds link the 2D sheets leading to a pseudo 3D network, while the stability of the structure is assured by a weak π-π stacking between parallel and opposed phen ligands.The Ce3+ cation is nona-coordinated and it is in a distorted tricapped trigonal prism geometry.Hirshfeld surface analysis was used to investigate the non-covalent intermolecular interactions and the dominant H···O, H···C and H···H contacts were quantified. The thermal properties of the considered coordination polymer (I) are also discussed and disclose that (I) is stable up to 300°C. Besides, this study explores the potential of (I) as an inhibitor of the carbonic anhydrase IX enzyme (CA IX), a critical player in tumor microenvironment regulation. Through molecular docking simulations, we elucidate the binding interactions between (I) and CA IX, the results suggest the efficiency of (I) as a CA IX inhibitor. Moreover, we assessed the drug-likeness properties and ADMET characteristics of (I), providing valuable insights for its potential as a therapeutic agent.

Titanium (IV) μ-Oxo Complex Supported by Phenoxyimine Ligand: Synthesis, Crystal Structure Characterisation, DFT and Molecular Docking Studies

Background: Most of the transition elements in the 3d series (first row transition metals) have been discovered to be extremely significant and practical in biological systems. Naturally, many of the enzymes that are present in the human body system act as catalysts for biological processes and are made of coordination compounds or complexes. Objective: The complex has been characterised by various spectroscopic and analytic techniques. A suitable crystal analysed by X-ray diffraction establishes the formation of a stable binuclear µ-oxo-complex with a hexacoordinate titanium centre. Methods: A new crystalline complex [Ti{La}] has been synthesised in the reaction of titanium butoxide with a phenoxyimine ligand in a 1:1 stoichiometry in toluene at room temperature under a nitrogen atmosphere. The newly synthesised Ti complex has undergone density functional theory and docking study. Results: The crystal shows a monoclinic system with space group C 1 2/c 1. X-ray crystal structure analysis reveals that this complex has a rhomboidal Ti-O-Ti core and exhibits a C2 symmetric conformation with distorted octahedral geometry. Density Functional Theory (DFT) calculations giving insights into the frontier orbitals and mulliken charge analysis, which showed good correlation with the experimental findings. Additionally, in silico molecular docking of ligand and complex was carried out against the HER2 inhibitor kinase. Conclusion: This complex exhibits a higher binding energy of ΔGb = -19.7 kcal/mol with the active pocket of HER2 (PDB:7JXH) than the ligand ΔGb = -8.5 kcal/mol.

A polymeric Co(II) oxalate salt containing pyridinium type cations: Synthesis, structure, spectroscopy, thermal behavior and magnetism

A Co(II) oxalate coordination polymer, (C7H11N2)2[Co(C2O4)2]·5H2O (1) (C7H11N2+ = 2-amino-4,6-dimethylpyridinium cation), has been synthesized and characterized by elemental and thermal analyses, FT-IR and UV/Vis spectroscopies, powder X-ray diffraction (PXRD), single-crystal X-ray diffraction and variable temperature magnetic susceptibility measurements. Compound 1 is a polymerized organic–inorganic hybrid salt, the asymmetric unit of which consists of one Co(II) ion, one bidentate C2O42− ligand, two halves of bidentate C2O42− ligands, two 2-amino-4,6-dimethylpyridinium C7H11N2+ cations and five crystal water molecules. Each CoII center is six-coordinated in a distorted octahedral geometry fulfilled by six oxygen atoms from three chelating C2O42− ligands. The [Co(C2O4)2]2− ions act as complex ligands and efficiently bridge neighboring Co2+ ions, forming chains of complex anions linked by hydrogen bonded water molecules. Hydrogen bonding interactions of the type OH∙∙∙O and NH∙∙∙O along with π–π stacking interactions between pyridine rings contribute to the stabilization of the 3D supramolecular framework. Temperature-dependence magnetic moment (µ) collected under zero-field cooled (ZFC) and field-cooled (FC) conditions revealed weak antiferromagnetic ordering at low temperatures.

Synthesis and Characterization New 1, 2, 4-Triazole Derivative and Its Complexes with Some Transition Metal Ions

An innovative class of ligand compounds using The ions of transition metals (Cr(III), Fe(III), and Ni(II)).The ligand N,N'-(4H-1,2,4-triazole-3,5-diyl)bis(4-methoxybenzamide) was produced by reacting 2,5-di amino-1,2,4-triazole with two moles of methyl 4-methoxybenzoate in the presence of ethanol and a few drops of glacial acetic acid. The recently produced chemicals were studied using a battery of analytical tools, analysis of elements (C, H, and N), nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, mass spectrometry, and atomic absorption are some of the techniques that are included. The aforementioned diagnostic procedures led to the formation of ligand-containing octahedral complexes with (Fe and Cr) ions and a square planer complex with nickel.

Copper and nickel complexes based on 4-((4-nitrophenyl)diazenyl)-3-(trifluoromethyl)-1H-pyrazol-5-ol; synthesis, characterization, X-ray studies, DFT calculations, molecular docking and antimicrobial activity

Two new copper(II) and nickel(II) complexes were prepared using 4-((4-nitrophenyl)diazenyl)-3-(trifluoromethyl)-1H-pyrazol-5-ol (ndtp) and well-characterized spectroscopically and thermally and via X-ray studies. X-ray studies confirmed the formation of two octahedral complexes, containing two ndtp and two coordinated DMF molecules. The two complexes were evaluated in vitro against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus cereus. [Ni(ndtp)2(DMF)2] showed an enhanced antibacterial activity against the different bacterial strains compared to the free ligand and that of the [Cu(ndtp)2(DMF)2]. The mean inhibition zones exhibited by [Ni(ndtp)2(DMF)2] were 14.7±0.6, 14.0±1.0, and 16.3±0.6 mm against Escherichia coli, Staphylococcus aureus and Bacillus cereus, respectively. Molecular docking studies of the two complexes were performed with DNA gyrase of Escherichia coli (PDB ID: 6F86) to evaluate the potential antibacterial activities, and it was proved that the complexes were efficient for the receptor.

Synthesis, Characterization, Investigation of DNA Interactions and Biological Evaluation of Co(II), Ni(II), Cu(II) and Zn(II) Complexes with Newly Synthesized 2-methoxy 5-trifluoromethyl benzenamine Schiff Base.

The biologically active and thermally stable bivalent Co(II), Ni(II), Cu(II), and Zn(II) complexes (C1, C2, C3, and C4) of novel Schiff base ligand [(5-trifluoromethyl-2-methoxyphenylamino)methyl)-4,6-diiodophenol (L)] have been synthesized. The structural analysis of these complexes have been carried out by elemental analysis, 1H-NMR, FTIR, ESI mass, UV-visible, ESR, TGA techniques and magnetic measurements. The obtained results were confirmed as square planar geometry for Ni(II) and Cu(II) complexes, whereas octahedral geometry for Co(II) and Zn(II) complexes. The geometry optimized structures were developed by employing CHEM 3D software. The DNA binding interaction studies such as UV-vis absorption, viscosity, and fluorescence studies have been confirmed that the mode of binding of complexes with DNA is an intercalative binding. The DNA cleavage studies revealed that all the complexes are found to be potent to cleave the DNA into Form I & II. The in-vitro pathological studies of all the complexes against various microbial strains (Gram + and Gram -), revealed that Cu(II) complexes are more potent compared to other complexes and Schiff base. The anti diabetic activity studies revealed that the Cu(II) complex exhibited slightly higher activity than Co(II), Ni(II), and Zn(II) complexes. The results of antioxidant activity by DPPH method, suggested that the Cu(II) complex has higher activity and comparable with the standard compounds.

DNA Interaction, Molecular Docking, Antimicrobial, Anticancer and Thermal Studies of Ternary Metal Complexes of N‐Methylbenzylamine and Ethylenediamine

ABSTRACTN‐Methylbenzylamine and ethylenediamine were utilized as primary and auxiliary ligands, respectively, alongside metal salts to synthesize ternary metal complexes: [FeCl3(Nmba)(en)], [CoCl2(Nmba)(en)(H2O)] and [CuCl2(Nmba)(en)(H2O)]. These complexes were thoroughly characterized using spectral and analytical techniques, revealing an octahedral geometry for all. Coats–Redfern calculations indicated their non‐spontaneous nature yet highlighted their thermal stability. DNA binding studies unveiled a groove binding mode for the complexes, with intrinsic binding constants (Kb) and Stern–Volmer quenching constant (Ksq) supporting their strong binding capabilities. Nuclease activity against pBR322 was assessed through gel electrophoresis. Additionally, docking studies using AutoDock 4.2 software provided insights into their binding affinities. In terms of biological activities, the Cu complex demonstrated superior cytotoxicity and antibacterial and antifungal properties compared to the other ternary metal complexes. This suggests its potential for further exploration in biomedical applications.

Three-dimensional alkaline earth metal-organic framework poly[[μ-aqua-aqua-bis-(μ3-carba-moyl-cyano-nitro-somethanido)barium] monohydrate] and its thermal decomposition.

In the structure of the title salt, {[Ba(μ3-C3H2N3O2)2(μ-H2O)(H2O)]·H2O} n , the barium ion and all three oxygen atoms of the water mol-ecules reside on a mirror plane. The hydrogen atoms of the bridging water and the solvate water mol-ecules are arranged across a mirror plane whereas all atoms of the monodentate aqua ligand are situated on this mirror plane. The distorted ninefold coord-ination of the Ba ions is completed with four nitroso-, two carbonyl- and three aqua-O atoms at the distances of 2.763 (3)-2.961 (4) Å and it is best described as tricapped trigonal prism. The three-dimensional framework structure is formed by face-sharing of the trigonal prisms, via μ-nitroso- and μ-aqua-O atoms, and also by the bridging coordination of the anions via carbonyl-O atoms occupying two out of the three cap positions. The solvate water mol-ecules populate the crystal channels and facilitate a set of four directional hydrogen bonds. The principal Ba-carbamoyl-cyano-nitro-somethanido linkage reveals a rare example of the inherently polar binodal six- and three-coordinated bipartite topology (three-letter notation sit). It suggests that small resonance-stabilized cyano-nitroso anions can be utilized as bridging ligands for the supra-molecular synthesis of MOF solids. Such an outcome may be anti-cipated for a broader range of hard Lewis acidic alkaline earth metal ions, which perfectly match the coordination preferences of highly nucleophilic nitroso-O atoms. Thermal analysis reveals two-stage dehydration of the title compound (383 and 473 K) followed by decomposition with release of CO2, HCN and H2O at 558 K.

Anion-pairing effect in Cd(II) coordination with a tetrabenzotetraza-crown macrocyclic ligand

Three new complexes of a tetrabenzotetraza-crown ether macrocyclic ligand (L) with Cd(II) chloride (1), iodide (2), and acetate (3) salts were synthesized and characterized by FT-IR, 1H NMR spectroscopy, elemental microanalysis, and single crystal X-ray diffraction. Complex 1 has the formula [Cd(L)Cl]2 [CdCl4] with two square pyramidal [Cd(L)Cl]+ subunits interconnected through the CdCl42− counter anion. Meanwhile, the reaction with CdI2 produces the discrete complex [Cd(L)I]I (2) with an octahedral geometry about the Cd(II) center. A distorted six-coordinated asymmetric unit was observed for [Cd(L)OAc]2(OAc·H2O)2 (3), wherein two [Cd(L)OAc]+ subunits are held together by a flat (OAc·H2O)2 acetate-water cluster. Hirshfeld Surface calculations were applied to confirm the dominant interactions in 1–3, namely π–π, and X⋯H/H⋯X (X-H, C, O, and halogen) interactions as the main factors for their structural differences. At the same time, the structure of [Cd(L)L′]+ (L′ = Cl, I, and OAc) core remained almost unchanged. The Cd(II) coordination with L in the presence of different Cd(II) salts was followed by 1H NMR spectroscopy. All three Cd(II) salt displays 1:1 stoichiometry, with binding constants in the order CdCl2 < CdI2 < Cd(OAc)2.

Synthesis, crystal structure and Hirshfeld surface analysis of a new copper(II) complex based on diethyl 2,2'-(4H-1,2,4-triazole-3,5-di-yl)di-acetate.

The title compound, bis-[μ-2,2'-(4H-1,2,4-triazole-3,5-di-yl)di-acetato]-bis-[di-aqua-copper(II)] dihydrate, [Cu2(C6H5N3O4)2(H2O)4]·2H2O, is a dinuclear octa-hedral CuII triazole-based complex. The central copper atoms are hexa-coordinated by two nitro-gen atoms in the equatorial positions, two equatorial oxygen atoms of two carboxyl-ate substituents in position 3 and 5 of the 1,2,4-triazole ring, and two axial oxygen atoms of two water mol-ecules. Two additional solvent water mol-ecules are linked to the title mol-ecule by O-H⋯N and O⋯H-O hydrogen bonds. The crystal structure is built up from the parallel packing of discrete supra-molecular chains running along the a-axis direction. Hirshfeld surface analysis suggests that the most important contributions to the surface contacts are from H⋯O/O⋯H (53.5%), H⋯H (28.1%), O⋯O (6.3%) and H⋯C/C⋯H (6.2%) inter-actions. The crystal studied was twinned by a twofold rotation around [100].