Synthesis, characterization, DNA binding, and biological action of dimedone arylhydrazone chelates

Synthesis, Biological Properties, and Molecular Docking Study of Novel 1,2,3-Triazole-8-quinolinol Hybrids

A new series of 1,2,3-triazole-8-quinolinol hybrids were synthesized in good yields using monosubstituted acetonitriles and 5-azidomethyl-8-quinolinol as the starting reagents via a one-step protocol. The structures of 1,2,3-triazole-8-quinolinol hybrids were characterized by nuclear magnetic resonance (1H and 13C NMR) spectroscopy and elemental analysis. Antibacterial activity in vitro of all the synthesized hybrids was investigated against Escherichia coli (E. coli), Xanthomonas fragariae (X. fragariae), Staphylococcus aureus (S. aureus), and Bacillus subtilis (B. subtilis) applying the methods of disk diffusion and minimal inhibition concentration (MIC). Hybrid 7 exhibited excellent antibacterial capacity, with an MIC value of 10 μg/mL against S. aureus and 20 μg/mL against B. subtilis, E. coli, and X. fragariae, which were comparable to those that of the standard antibiotic nitroxoline. A structure-activity relationship (SAR) study of 1,2,3-triazole-8-quinolinol hybrids showed that introducing electron-donating substituents in the 1,2,3-triazole ring at the 4-position is important for activity. Quantum chemical calculations have been undertaken to employ the Gaussian software in the B3LYP, HF, and M062X basis sets using 3-21g, 6-31g, and SDD levels to further explain linkages within the antibacterial findings. Furthermore, molecular docking investigations were also conducted to investigate the binding affinities as well as the interactions of some hybrids with the target proteins. An absorption, distribution, metabolism, excretion, and toxicity (ADME/T) investigation was carried out to scrutinize the viability of employing the 1,2,3-triazole-8-quinolinol hybrids as medicines.

Design, synthesis, characterization, in vitro cytotoxic, antimicrobial, antioxidant studies, DFT, thermal and molecular docking evaluation of biocompatible Co(II) complexes of N4O4-macrocyclic ligands

Bioactive cobalt (II) macrocyclic complexes [Co(N4O4ML1)Cl2]-[Co(N4O4ML3)Cl2] have been synthesized by using the macrocyclic ligands [N4O4ML1], [N4O4ML2], and [N4O4ML3] that have an N4O4 core. These three macrocyclic ligands were all isolated in pure form, together with their complexes. Microanalytical investigations, FT-IR NMR, Mass, magnetic moments, electronic, PXRD, TGA, and EPR spectrum studies were used to analyse their structures. For these complexes, an octahedral geometry is proposed for the metal ion. By using molecular weights and conductivity measurements the monomeric and non-electrolytic nature has been confirmed. The Coats-Redfern and FWO methods are used to determine the thermodynamic characteristics of the ligands and their Co(II) complexes. The molecular modelling using the DFT technique displays the bond angle, bond lengths and quantum chemical properties. To determine their ability to prevent the growth of harmful fungus and bacteria, the ligands [N4O4ML1]- [N4O4ML3] and their complexes were tested in vitro against A. Niger, C. albicans and B. subtilis, S. aureus, E. coli and S. typhi fungal and bacterial organisms, respectively. By using DPPH free radical scavenger assays, the in vitro antioxidant capabilities of each compound were evaluated. The [Co(N4O4ML3)Cl2] antioxidative capabilities revealed significant radical scavenging power. The MTT assay was used to assess the toxicity of all the synthesised compounds under inquiry on MCF-7, HeLa, and A549 cancer cells. The findings revealed that the ligand and the compounds gave outstanding IC50 values in the range of 9.07-36.25 (uM) at a concentration of 25 ppm. Among all the substances evaluated, [Co(N4O4ML3)Cl2] complex was discovered to be the most active and least cytotoxic. Additionally, docking investigations of the produced compounds were carried out in order to validate the biological outcomes.

Synthesis, Characterization and Evaluation of the Antimicrobial and Herbicidal Activities of Some Transition Metal Ions Complexes with the Tranexamic Acid

New tranexamic acid (TXA) complexes of ferric(III), cobalt(II), nickel(II), copper(II) and zirconium(IV) were synthesized and characterized by elemental analysis (CHN), conductimetric (Λ), magnetic susceptibility investigations (μeff), Fourier transform infrared (FT-IR), proton nuclear magnetic resonance (1H-NMR), ultraviolet visible (UV-vis.), optical band gap energy (Eg) and thermal studies (TG/DTG and DTA). TXA complexes were established in 1 : 2 (metal: ligand) stoichiometric ratio according to CHN data. Based on FT-IR and 1H-NMR data the disappeared of the carboxylic proton supported the deprotonating of TXA and linked to metal ions via the carboxylate group's oxygen atom as a bidentate ligand. UV-visible spectra and magnetic moment demonstrated that all chelates have geometric octahedral structures. Eg values indicated that our complexes are more electro conductive. DTA revealed presence of water molecules in inner and outer spheres of the complexes. DTA results showed that endothermic and exothermic peaks were identified in the degradation mechanisms. The ligand and metal complexes were investigated for their antimicrobial and herbicidal efficacy. The Co(II) and Ni(II) complexes showed antimicrobial activity against some tested species. The obtained results showed a promising herbicidal effect of TXA ligand and its metal complexes particularly copper and zirconium against the three tested plants.

Supramolecular clumps of μ2-1,3-acetate bridges of Cd(II)-Salen complex: Synthesis, spectroscopic characterization, crystal structure, DFT quantization's, and antifungal photodynamic therapy

The article divulges the crystal growth, synthesis, and X-ray structure characterization of one centrosymmetric cadmium complex, [Cd{CdL(μ2-1,3-acetate)}2] using Salen ligand (SL). The complex is further characterized using spectroscopic and analytical techniques, including DRS, SEM-EDX, PXRD, and ICP-MS. The crystallographic study showed that the complex has a monoclinic space P21/c. Addison parameters (Ʈ) show the hexagonal geometry of the central Cd(II) metal ion. Hirshfeld surface and 2-D fingerprint confirm supramolecular contacts despite weak C-H⋯O and C-H···π interactions. Energy frameworks, FMOs, global reactivity parameters, MEP, and energy bandgap explain the complex reactivity outlook. The complex inter- and intramolecular bonding interactions were explored through natural bond orbital (NBO), QTAIM, NCI-RDG, Electron Location Function (ELF), and Localized Orbital Locator (LOL) quantization methods. In addition, the complex and its synthetic components in vitro antibacterial efficacy were investigated using Gram-positive and Gram-negative microbial strains. SAR (structure-activity relationship) correlates with biological potency. Molecular docking assessed antimicrobial potency with proteins S. aureus (PDB ID: 1JIJ), C. albicans (PDB ID: 1M7A), E. coli (PDB ID: 1T9U), P. aeruginosa (PDB ID: 2UV0), and A. Niger (PDB ID: 3K4P). The findings are backed by the Protein-Ligand Interaction Profiler (PLIP). The antifungal potency and cell viability test of C. albicans were conducted using photodynamic therapy (APDT).

Refashioning of the drug-properties of fluoroquinolone through the synthesis of a levofloxacin-imidazole cobalt (II) complex and its interaction studies on with DNA and BSA biopolymers, antimicrobial and cytotoxic studies on breast cancer cell lines

Levofloxacin (HLVX), a quinolone antimicrobial agent, when deprotonated (LVX-) behaves as a bidentate ligand, and it coordinates to Co2+ through the pyridone oxygen and the carboxylate oxygen. Along with two imidazole (ImH) ligands, levofloxacin forms a Co(II)-Levofloxacin-imidazole complex, [CoCl(LVX)(ImH)2(H2O)]·3H2O (abbreviated henceforth as CoLevim) which was isolated and characterized by 1H and 13C NMR spectroscopy, UV-visible and FT-IR spectroscopy, powder X-ray diffraction and thermal analysis methods. CoLevim shows promise in its antimicrobial activities when tested against microorganisms (Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Salmonella typhimurium and Escherichia coli). Fluorescence competitive studies with ethidium bromide (EB) revealed that CoLevim can compete with EB and displace it to bind to CT-DNA through intercalative binding mode. In addition, CoLevim exhibited a good binding propensity to BSA proteins with relatively high binding constants. The antioxidant activities of the free ligands and CoLevim were determined in vitro using ABTS+ radical (TEAC assay). The Co-complex showed a better antioxidant capacity with inhibitory concentrations (IC50) of 40 μM than the free ligands. CoLevim also showed noteworthy apoptotic potential and behaved as an efficient resistant modifying agent when its antiproliferative potential was examined by MTT assay using the breast cancer cell lines (MCF7, MCF7Dox/R and MCF7Pacli/R cells).

Characterization, Antioxidant, and Antimicrobial Properties of Mulberry Lattices

In order to find the most advantageous bioactive compounds from mulberry latex for drug development in the near future, this study was conducted to characterize and evaluate antioxidant and antimicrobial properties from four different mulberry lattices (BR-2, S-1, AR-14, and S-146). The characterization of the lattices was performed by scanning electron microscopy with energy-dispersive X-ray spectroscopy, gas chromatography coupled to mass spectroscopy, and Fourier transform infrared spectroscopy. Further, screenings of the antioxidant and antimicrobial potential of selected lattices were performed in vitro using 2,2-diphenyl-1-picrylhydrazyl assay and agar well diffusion methods, respectively. Interestingly, the outcome of the current study revealed that tested mulberry lattices contain a considerable amount of bioactive phytoconstituents, particularly antimicrobial and antioxidant compounds, as revealed by chromatographic analysis. BR-2 latex was found to have significant antioxidant activity (75%) followed by S-146 (64.6%) and AR-14 (52.9%). The maximum antimicrobial activity was found in BR-2 latex compared to other tested latex varieties. The results of this investigation showed that mulberry latex from the BR-2 type may successfully control both bacterial and fungal infections, with the added benefit of having enhanced antioxidant capabilities.

Novel Schiff Base Derived from Amino Pyrene: Synthesis, Characterization, Crystal Structure Determination, and Anticancer Applications of the Ligand and Its Metal Complexes

In this study, we report the cytotoxicity of a newly synthesized Schiff base HL ((E)-2-ethoxy-6((pyren-1-ylimino)methyl)phenol) and its derived metal complexes (Zn(II), Cu(II), Co(II), Cr(III), and Fe(III)) along with their structural characterizations by means of elemental analysis, magnetic moment, molar conductance, IR, UV-Vis, ESR, and mass spectrometry. The single X-ray diffraction of the HL shows that it exists in the phenol-imine form in its solid state. The NMR and IR data indicate that the bidentate binding of the Schiff base ligand with the metal center occurs during complexation through the azomethine nitrogen atom and the hydroxyl group oxygen atom of the 3-ethoxy salicylaldehyde. The electronic spectra and magnetic measurements indicate that the Co(II) complex has a tetrahedral geometry and that the Cr(III) and Fe(III) complexes have a distorted octahedral geometry. The ESR and electronic spectra suggest that the Cu(II) complex has a distorted tetrahedral geometry. The cytotoxic effects of the HL and all of the metal complexes were studied using human breast cancer (MCF-7) cells. The Cu(II) and Zn(II) complexes exhibited the highest activity against the tested cell line, with IC50 values of 5.66 and 12.74 μg/mL, respectively, and their activity was higher than that of the fluorouracil cancer drug against the MCF-7 cells (18.05 μg/mL).

Synthesis, structural characterization, antioxidant, cytotoxic activities and docking studies of schiff base Cu(II) complexes

By combining hydrazide with 2-Acetylpyridine, a hydrazone ligand (HL) was successfully created. Several copper (II) salts have been used to create three copper (II) hydrazone complexes (acetate, sulphate, and chloride). The hydrazide ligand and its copper (II) complexes (1-3) were studied via variety of analytical techniques, including elemental analysis, electronic, infrared, UV-vis Spectrum, XRD study, thermal analysis, also molar conductivity amounts. The spectrum results indicate that in all complexes, the ligand exhibits monobasic tridentate behavior. Octahedral geometries were present in all metal complexes. The Coats-Redfern equations were used to compute and describe the dynamics properties of several steps of TGA (Ea, A, ΔH*, ΔS*, and ΔG*). Calculations using the density functional theory (DFT) were done at the molecular studio software toward examine ligands agent's and its complexes' best structures. The MCF-7 in addition to HepG-2 cell lines was resistant to tumor-inducing effects of the copper (II) chelates. The in vitro antioxidant capacities of all complexes have been estimated via DPPH free radical scavenger assays. Furthermore, zones of inhibition length accustomed to test antimicrobial effect of particular complexes in vitro towards Staphylococcus aureus (Gram positive bacteria) E. coli (Gram negative bacteria). Both absorption spectra and viscosity measurements in calf thymus DNA binding have been used to study the complexes. In order to explore docking research of copper (II) chelates, the crystallographic construction of the SARS-active CoV-2's site protein (PDB ID:6XBH) was used (COVID-19) and breast cancer distorted (PDB ID: 3hb5).

Synthesis, characterization, DFT calculations and biological activity of new Schiff base complexes

Schiff bases ligand (HL) was produced by condensing 4-aminobenzohydrazide with N-(4-chlorophenyl)-2-(4-formylphenoxy)acetamide. Cobalt (II), nickel (II), and copper (II) acetate and ligand are reacted to form 1:1 complexes. By using electronic spectra, magnetic susceptibility measurements, infrared data from 1H NMR, and XRD studies, the ligand and its metal complexes have been characterized. According to the spectrum data, the ligand functions as a monobasic bidentate, coordinating with the nitrogen atom of azomethine (-C[bond, double bond]N-) group and the oxygen atom of carbonyl group in enol form. An octahedral structure has been proposed for Co(II), Ni(II), and Cu(II) complexes according to magnetic and electronic spectrum analysis. Using the DFT method, the computational investigations of the ligand and its metal complexes showed the bond lengths, bond angles, and quantum chemical parameters. To determine the thermal stability and mode of thermal degradation of hydrazone ligand and its complexes, thermogravimetric analysis was approved out on the samples. Two calculated method, Horowitz-Metzger and Coats-Redfern, were used to calculate the characteristics of the composites' thermal degradation mechanisms at each step, including their breakdown kinetics. The ligand and its complexes were investigated for their cytotoxicity in vitro compared to human amnion (WISH) and epitheliod carcinoma (Hela). The Ni(II) complex showed highly inhibition against (WISH) growth (IC50 = 18.28±1.8 μM) with relationship to the produced chemicals and other common medications. The interaction between the ligand and its complexes with the genetic tumor (3hb5) receptor was examined using docking experiments.

Albalawi S, M. Al-Zaydi K, Said MA. Synthesis of Silver(I) Complexes Containing 3-Oxo-3-phenyl-2-(2-phenylhydrazono)propanal-Based Ligands as a Multifunction Platform for Antimicrobial and Optoelectronic Applications

Toward multifunctionality, including antimicrobial and optoelectronic applications, herein, we reported the synthesis of a novel Ag(I) complex with 3-oxo-3-phenyl-2-(2-phenylhydrazono)propanal-based ligands including 3-(4-chlorophenyl)-2-[2-(4-nitrophenyl)hydrazono]-3-oxopropanal (named as "4A"), 3-(4-chlorophenyl)-2-[2-(4-methylphenyl)hydrazono]-3-oxopropanal (named as "6A"), and 3-(4-chlorophenyl)-3-oxo-2-(2-phenylhydrazono)propanal (named as "9A"). The synthesized compounds were characterized through FTIR, ¹H NMR, and density functional theory (DFT). The morphological features and thermal stability were evaluated through transmission electron microscopy (TEM) and TG/DTA analysis. The antimicrobial activity of the synthesized Ag complexes was tested against various pathogens, including Gram-negative bacteria (Escherichia coli and Klebsiella pneumonia), Gram-positive bacteria (Staphylococcus aureus and Streptococcus mutans), and fungi (Candida albicans and Aspergillus niger). Results show that the synthesized complexes (Ag(4A), Ag(6A), and Ag(9A)) possess promising antimicrobial efficacy against various pathogens and are in good competition with several standard drugs as well. On the other hand, the optoelectronic features such as absorbance, band gap, and Urbach energy were examined by measuring the absorbance using a UV-vis spectrophotometer. The values of the band gap reflected the semiconducting nature of these complexes. The complexation with Ag resulted in a lowering band gap to match the apex of the solar spectrum. Such low band gap values are preferable for optoelectronic applications like dye-sensitized solar cells, photodiodes, and photocatalysis.

Thermodynamic and structural profiles of multi-target binding of vinblastine in solution

Structural information about drug-receptor interactions is paramount in drug discovery and subsequent optimization processes. Drugs can bind to multiple potential targets as they contain common chemical entities in their structures. Understanding the details of such interactions offer possibilities for repurposing and developing potent inhibitors of disease pathways. Vinblastine (VLB) is a potent anticancer molecule showing multiple receptor interactions with different affinities and degrees of structural perturbations. We have investigated the multi-target binding profile of VLB with DNA and human serum albumin (HSA) in a dynamic physiological environment using spectroscopic, molecular dynamics simulations, and quantum mechanical calculations to evaluate the structural features, mode, ligand and receptor flexibility, and energetics of complexation. These results confirm that VLB prefers to bind in the major groove of DNA with some inclination toward Thymidine residue and the TR-5 binding site in HSA with its catharanthine half making important contacts with both the receptors. Spectroscopic investigation at multiple temperatures has also proved that VLB binding is entropy driven indicating the major groove and TR-5 binding site of interaction. Finally, the overall binding is facilitated by van der Waals contacts and a few conventional H-bonds. VLB portrays reasonable conformational diversity on binding with multiple receptors.

Biogenic Synthesis of Silver Nanoparticles Using Phagnalon niveum and Its In Vivo Anti-Diabetic Effect against Alloxan-Induced Diabetic Wistar Rats

Background: Type-2 diabetes mellitus (T2DM) is a non-communicable, life-threatening syndrome that is present all over the world. The use of eco-friendly, cost-effective and green synthesised nanoparticles (NPs) as a medicinal therapy in the treatment of T2DM is an attractive option. Aim: The present study aimed to evaluate the anti-diabetic potential of the phyto-synthesised silver nanoparticles (AgNPs) obtained from Phagnalon niveum plant methanolic extract. Methods: The green synthesised AgNPs made from Phagnalon niveum plant methanolic extract were analysed by Ultraviolet-Visible (UV-Vis) spectroscopy, and the functional groups involved in the reduction of the silver ions (Ag⁺) were characterised by Fourier Transform Infrared (FTIR) spectroscopy. The size and crystallinity were assessed via X-ray Diffraction (XRD). The morphology of AgNPs was confirmed using Scanning Electron Microscopy (SEM). The amount of silver (Ag) was estimated via energy dispersive X-ray (EDX) analysis. An intraperitoneal injection of 200 mg alloxan per kg albino Wistar rats’ body weight, at eight weeks old and weighing 140–150 g, was used to induce diabetes mellitus (N = 25; n = 5/group). Group C: untreated normal control rats that only received distilled water, group DAC: diabetic control rats that received alloxan 200 mg/Kg body weight, DG: diabetic rats treated with glibenclamide at 0.5 mg/kg body weight, DE: diabetic rats that received methanolic P. niveum extract at 10 mg/Kg body weight, and DAgNPs: diabetic rates that received AgNPs synthesised from P. niveum at 10 mg/kg body weight. The blood glucose levels were monitored on days 0, 7, and 14, while lipid, liver, and kidney profiles were checked after dissection at the end of treatment (day 21). On the final day of the period study (day 21), an oral glucose tolerance test was carried out by administering orally 2 g/kg body weight of glucose to the respective groups, and the blood glucose level was checked. A fasting glucose level was measured using a glucometer. Urine samples were collected from each animal and analysed using lab-made assay kits for glucose, bilirubin, pH, leukocytes, and nitrite, among other factors. For statistical analyses, a one-way ANOVA and Dunnett’s test were applied. Results: The green-mediated synthesis of AgNPs using P. niveum methanolic extract produced spherical and mono-dispersed NPs with a size ranging from 12 to 28 nm (average: 21 nm). Importantly, a significant reduction of blood glucose levels and an increase in body weight, as well as a remarkable improvement in lipid, liver, and kidney profiles, were noticed. Conclusions: The biosynthesised AgNPs significantly improved the abnormalities in body weight, urine, and serum levels, indicating that it is a promising anti-diabetic agent.

Synthesis and characterization of novel copper(ii) complexes as potential drug candidates against SARS-CoV-2 main protease

Two novel copper(ii) Schiff base complexes, [Cu(L1)2] (1) and [Cu(L2)(CH3OH)(Cl)] (2) of [(Z)-(5-chloro-2-((3,5-dichloro-2-hydroxybenzylidene)amino)phenyl)(phenyl)methanone (L1H) and (Z)-(2((5-bromo-2-hydroxybenzylidene)amino-5-chlorophenyl)(phenyl)methanone)(L2H)], have been designed, synthesized and characterized.