Non-Linear Optical Property and Biological Assays of Therapeutic Potentials Under In Vitro Conditions of Pd(II), Ag(I) and Cu(II) Complexes of 5-Diethyl amino-2-({2-[(2-hydroxy-Benzylidene)-amino]-phenylimino}-methyl)-phenol

Spectroscopic and theoretical approach of DNA interaction and anticancer studies of bio-pharmaceutically active pyrimidine derived Cu(II) and Zn(II) complexes

New metal(II) complexes (CuL2 and ZnL2) with pyrimidine appended Schiff base ligand (HL) were synthesized and characterized by diverse spectroscopic methods, reveals the proposed structure of metal(II) complexes possess square planar geometry. DNA interaction ability of isolated compounds was studied by UV-Visible, fluorescence, viscometric and electrochemical methods and the results showed that isolated compounds intercalated with calf thymus DNA (CT-DNA). In addition, anticancer activities of HL, CuL2, and ZnL2 have been evaluated by MTT assay, signifying moderate cytotoxic activity on selected cancer cell lines and less toxicity on NHDF normal cell line due to the specific targeting of pyrimidine analogues. Moreover, antioxidant activities of isolated compounds towards diverse free radicals have been studied by spectrophotometric methods. These results showed that CuL2 has better antioxidant ability than HL and ZnL2. Finally, antimicrobial activities of isolated compounds against selected antimicrobial pathogens exposed that CuL2 has better antimicrobial activity on E. coli and C. albicans than other antimicrobial pathogens. The DFT calculations have been done to get the optimized geometry of the ligand and the metal complexes. In order to get a broad understanding of the interactions of these synthesized metal complexes, a detailed molecular docking analysis is taken up.

Study of novel bidentate heterocyclic amine-based metal complexes and their biological activities: cytotoxicity and antimicrobial activity evaluation

Metallic antitumor drugs with heterocyclic ligands, such as novel AMI (amino methyl imidazole) complexes [Pd(AMI)Cl₂](1), [Cu(AMI)L¹](2), and [Cu(AMI)L²·2H₂O](3) where L¹ = oxalate and L² = malonate, were synthesized and characterized. Assessments included elemental analyses, mass spectrometry, Fourier transform-infrared spectroscopy, ultraviolet-visible spectroscopy, and thermal analysis. The cytotoxicity of AMI complexes compared to cisplatin was assessed using MTT (3-[4,5-dimethylthiazol-2-yl] 2,5diphenyl tetrazolium bromide) assay with breast (MCF-7) and cervical (HeLa) cancer cell lines. After treating these cells with the AMI complexes' IC₅₀ values for 48 h, malondialdehyde levels and catalase activity were used to assess oxidative stress, antioxidant activity was evaluated with DPPH radical scavenging method, comet assays assessed DNA damage, and DNA fragmentation was evaluated using the gel electrophoresis. In vitro, antimicrobial activity was assessed using a disc diffusion method. The anticancer activity results showed that IC₅₀ (half-maximal inhibitory concentration) values of complex one, two, and three against MCF-7 and HeLa cancer cells are 0.156 ± 0.0006, 0.125 ± 0.001, 0.277 ± 0.002 μM respectively for MCF-7 cells and 0.222 ± 0.0005, 0.126 ± 0.0009, 0.152 ± 0.001 μM respectively for HeLa cells. Complex two demonstrated strong anticancer activity against MCF-7 and Hela cells. The study of oxidative stress parameters revealed that Malondialdehyde levels increased in cancer cell lines treated with complexes compared to untreated cells. Catalase activity decreased in cells treated with palladium chelate. The DPPH radical scavenging assay results identified that complex one was a more potent antioxidant in MCF-7 and Hela cells than other complexes with SC₅₀ values of 227.5 ± 0.28 and 361 ± 1.2 μL/mL, respectively. The comet assay results showed that complex two caused significant DNA damage in MCF-7 and HeLa cancer cells treated. Antimicrobial assays identified complex three as the most effective. Copper complexes give better antifungal activity against A. flavus than the palladium complex. We conclude that complex two is the most active in both cell types and might be assessed as a clinically useful drug for breast cancer treatment. The significance of the current study is the synthesis of antitumor drugs containing heterocyclic ligands, such as novel AMI complexes, and the study of their biological activities.

Development of New Azomethine Metal Chelates Derived from Isatin: DFT and Pharmaceutical Studies

Through the condensation of isatin (indoline-2, 3-dione) and aniline in a 1:1 ratio, a Schiff base ligand was synthesized and characterized via (¹H-NMR, mass, IR, UV-Vis) spectra. Elemental analyses, spectroscopy (¹H-NMR, mass, UV-Vis), magnetic susceptibility, molar conductivity, mass spectra, scanning electron microscope (SEM), and thermal analysis have all been used to characterize a series of Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II) metal complexes derived from the titled ligand. The metal-to-ligand ratio is 1:1, according to the analytical data. The Schiff base ligand displayed bidentate behavior with NO coordination sites when it bonded to metal ions, as seen by the IR spectra. The magnetic moment measurement and UV-Vis spectral investigation showed the octahedral geometry of the Cr(III), Fe(III), Co(II), Ni(II), and Zn(II) complexes, whereas they suggested the tetrahedral geometry of the Mn(II), Cu(II), and Cd(II) complexes. The thermal analysis study confirmed the presence of both hydrated and coordinated water molecules in all the compounds, except for the Mn(II) complex, and showed that the complexes decomposed in three or five decomposition steps leaving the corresponding metal oxide as a residue. The ligand and its metal complexes' antibacterial efficacy were evaluated. The findings showed that the metal complexes had stronger antibacterial properties than the ligand alone. The ligand and its metal complexes' anticancer properties were also investigated. A DFT investigation is also reported to gather information regarding the electronic features of the ligand and its metal complexes. Finally, drug-likeness and ADME characteristics were also calculated as parameters.

Enhanced In Vivo Wound Healing Efficacy of a Novel Hydrogel Loaded with Copper (II) Schiff Base Quinoline Complex (CuSQ) Solid Lipid Nanoparticles

Wound dressings created using nanotechnology are known as suitable substrates to speed up the healing of both acute and chronic wounds. Therapeutic substances can be delivered using these materials. In this study, a hydrogel loaded with Cu (II) Schiff base 8-hydroxy quinoline complex (CuSQ) solid lipid nanoparticles (SLN) was formulated to investigate its wound healing potential in an excision wound healing model in rats. The CuSQ SLN were spherical shaped with sizes ranging from 111 to 202 nm and a polydispersity index (PDI) ranging from 0.43 to 0.76, encapsulation efficiency (EE) % between 85 and 88, and zeta potential (ZP) of −11.8 to −40 mV. The formulated hydrogel showed good homogeneity, good stability, and a pH of 6.4 which indicates no skin irritation and had no cytotoxicity on the human skin fibroblast (HSF) cell line. In the in vivo study, animals were placed in five groups: control, standard, plain hydrogel, low dose, and high dose of CuSQ hydrogel. Both doses of CuSQ showed significantly faster healing rates compared to standard and control rats. In addition, the histopathology study showed more collagen, improved angiogenesis, and intact re-epithelization with less inflammation. A significant increase in transforming growth factor-beta1 (TGF-β1) level and increased immune expression of vascular endothelial growth factor (VEGF) by CuSQ treatment validates its role in collagen synthesis, proliferation of fibroblasts and enhancement of angiogenesis. Matrix metalloproteinase-9 (MMP-9) was found to be significantly reduced after CuSQ treatment. Immunohistochemistry of tumor necrosis factor alpha (TNF-α) revealed a marked decrease in inflammation. Thus, we concluded that CuSQ would be a beneficial drug for cutaneous wound healing since it effectively accelerated wound healing through regulation of various cytokines and growth factors.

Design, Structural Inspection and Bio-Medicinal Applications of Some Novel Imine Metal Complexes Based on Acetylferrocene

Some novel imine metal chelates with Cr³⁺, Mn²⁺, Fe³⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺, and Cd²⁺ cations were produced from 2-acetylferrocene and 3-aminophenol. The new acetylferrocene azomethine ligand ((Z)-cyclopenta-1,3-dien-1-yl(2-(1-((3-hydroxyphenyl)imino)ethyl)cyclopenta-2,4-dien-1-yl)iron) and its metal ion chelates were constructed and elucidated using FT-IR, UV/Vis, ¹HNMR, DTA/TGA, CHNClM studies, mass spectrometry and SEM analysis. According to the TGA/DTG investigation, the ferrocene moiety spontaneously disintegrates to liberate FeO. The morphology of the free acetylferrocene azomethine via SEM analysis was net-shaped with a size of 64.73 nm, which differed in Cd(II) complex to be a spongy shape with a size of 42.43 nm. The quantum chemical features of the azomethine ligand (HL) were computed, and its electronic and molecular structure was refined theoretically. The investigated acetylferrocene imine ligand behaves as bidinetate ligand towards the cations under study to form octahedral geometries in case of all complexes except in case of Zn²⁺ is tetrahedral. Various microorganisms were used to investigate the anti-pathogenic effects of the free acetylferrocene azomethine ligand and its metal chelates. Moreover, the prepared ligand and its metal complexes were tested for anticancer activity utilizing four different concentrations against the human breast cancer cell line (MCF7) and the normal melanocyte cell line (HBF4). Furthermore, the binding of 3-aminophenol, 2-acetylferrocene, HL, Mn²⁺, Cu²⁺, and Cd²⁺ metal chelates to the receptor of breast cancer mutant oxidoreductase was discovered using molecular docking (PDB ID: 3HB5).

Synthesis, Spectroscopic, Structural and Molecular Docking Studies of Some New Nano-Sized Ferrocene-Based Imine Chelates as Antimicrobial and Anticancer Agents

The newly synthesized organometallic acetyl ferrocene imine ligand (HL) was obtained by the direct combination of 2-acetyl ferrocene with 2-aminothiophenol. The electronic and molecular structure of acetyl ferrocene imine ligand (HL) was refined theoretically and the chemical quantum factors were computed. Complexes of the acetyl ferrocene imine ligand with metal(II)/(III) ions (Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II)) were fabricated. They were inspected by thermal (DTG/TG), spectroscopic techniques (FT-IR, 1H NMR, mass, UV-Vis), molar conductivity, and CHNClM to explicate their structures. Studies using scanning electron microscope (SEM) were conducted on the free acetyl ferrocene imine ligand and its Cd(II) chelate to confirm their nano-structure. To collect an idea about the effect of metal ions on anti-pathogenic properties upon chelation, the newly synthesized acetyl ferrocene imine ligand and some of its metal chelates were tested against a variety of microorganisms, including Bacillus subtilis, Staphylococcus aureus, Salmonella typhimurium, Escherichia coli, Aspergillus fumigatus, and Candida albicans. The ligand and its metal chelate were tested for cytotoxic activity in human cancer (MCF-7 cell viability) and human melanocyte cell line HBF4. It was discovered that the Cd(II) chelate had the lowest IC50 of the three and thus had the prior activity. Molecular docking was utilized to investigate the interaction of acetyl ferrocene imine ligand (HL) with the receptors of the vascular endothelial growth factor receptor VEGFR (PDB ID: 1Y6a), human Topo IIA-bound G-segment DNA crystal structure (PDB ID: 2RGR), and Escherichia coli crystal structure (PDB ID: 3T88).

A study of structure-activity relationship and anion-controlled quinolinyl Ag(I) complexes as antimicrobial and antioxidant agents as well as their interaction with macromolecules

In this communication, we feature the synthesis and in-depth characterization of a series of silver(I) complexes obtained from the complexation of quinolin-4-yl Schiff base ligands ((E)-2-((quinolin-4-ylmethylene)amino)phenol L_a, 2-(quinolin-4-yl)benzo[d]thiazole L_b, (E)-N-(2-fluorophenyl)-1-(quinolin-4-yl)methanimine L_c, (E)-N-(4-chlorophenyl)-1-(quinolin-4-yl)methanimine L_d, (E)-1-(quinolin-4-yl)-N-(p-tolyl)methanimine L_e, (E)-1-(quinolin-4-yl)-N-(thiophen-2-ylmethyl)methanimine L_f) and three different silver(I) anions (nitrate, perchlorate and triflate). Structurally, the complexes adopted different coordination geometries, which included distorted linear or distorted tetrahedral geometry. The complexes were evaluated in vitro for their potential antibacterial and antioxidant activities. In addition, their interactions with calf thymus-DNA (CT-DNA) and bovine serum albumin (BSA) were evaluated. All the complexes had a wide spectrum of effective antibacterial activity against gram-positive and gram-negative bacterial and good antioxidant properties. The interactions of the complexes with CT-DNA and BSA were observed to occur either through intercalation or through a minor groove binder, while the interaction of the complexes with BSA reveals that some of the complexes can strongly quench the fluorescence of BSA through the static mechanism. The molecular docking studies of the complexes were also done to further elucidate the modes of interaction with CT-DNA and BSA.

Theoretical Study of the Structural Stability, Chemical Reactivity, and Protein Interaction for NMP Compounds as Modulators of the Endocannabinoid System

The cannabinoid receptors (CB1/CB2) and the T-type calcium channels are involved in disorders associated with both physiological pain and depressive behaviors. Valuable pharmacological species carbazole derivatives such as the NMP-4, NMP-7, and NMP-181 (Neuro Molecular Production) regulate both biological entities. In this work, DFT calculations were performed to characterize theoretically their structural and chemical reactivity properties using the BP86/cc-pVTZ level of theory. The molecular orbital contributions and the chemical reactivity analysis reveal that a major participation of the carbazole group is in the donor-acceptor interactions of the NMP compounds. The DFT analysis on the NMP compounds provides insights into the relevant functional groups involved during the ligand-receptor interactions. Molecular docking analysis is used to reveal possible sites of interaction of the NMP compounds with the Cav3.2 calcium channel. The interaction energy values and reported experimental evidence indicate that the site denominated as "Pore-blocking", which is formed mainly by hydrophobic residues and the T586 residue, is a probable binding site for the NMP compounds.

Design, DFT studies, antimicrobial and antioxidant potential of Binuclear N-heterocyclic Carbene (NHCs) complexes, Probing the aspect of DNA interaction through In-vitro and In-silico approach

N-heterocyclic carbene (NHC) adducts have shown remarkable biological potential for numerous medical applications. With an aim to improve biological potential of benzimidazolium salts, newer analogues of benzimidazole and their silver complexes were synthesized and characterized. Synthesized salts (L₁-L₂) and silver complexes (C₁-C₂) were confirmed through elemental analysis, UV-visible spectroscopy, FTIR, ¹H NMR & ¹³C NMR spectroscopy. The compounds C1 & C2 were found stable in solution form for studied time period when examined spectroscopically and showed optimum lipophilicity when measured for their partition coefficient through flask shake method. Synthesized compounds showed good antimicrobial potential against gram positive bacterial strain S. Aureus with IC₅₀ 2.02±0.12 and 2.11±0.13 µM respectively while 2.11±0.1 and 2.28±0.17 µM against gram negative bacterial strain E. Coli for C1 and C2 respectively. The interaction study of the related compounds with DNA was predicted by molecular docking study, which confirmed that the studied compound C1 (-8.04 kcal/mol) has a higher binding energy than compound C2 (-4.23 kcal/mol); Also, the compound C1 exhibits a better affinity against to DNA than Ethidium bromide (-7.68 kcal/mol) and cisplatin (-6.21 kcal/mol).The claim was practically assured through spectroscopic and viscometeric method which confirmed that compounds have good affinity for DNA with binding constant kb, 5.78×10⁴ M^-1 and 6.84×10⁴ M^-1 for C1 and C2 respectively.

Temperature and salt effects of the kinetic reactions of substituted 2-pyridylmethylene-8-quinolyl iron (II) complexes as antimicrobial, anti-cancer, and antioxidant agents with cyanide ions

Kinetics of substitution reaction of three high-spin pyridylmethylene-8-quinolyl iron (II) complexes by CN– ions were studied spectrophotometrically in various ratios of aqueous–methanol binary mixtures at 298 ± 0.2 K. Kinetics of the substitution reaction follow the rate law (k2[CN−][complex]) on applying of the conditions of the pseudo first order reaction. Reactivity of the reaction was investigated in terms of ligand moiety and solvent effects. The rate of the reaction increased as the co-solvent methanol ratio increased. This reactivity trend is predominantly due to increases in the activity coefficient of those hydrophobic complexes in the organic methanol co-solvent, depending upon the hydrophobicity of the substituent groups (R) in the coordinated ligand in the complexes. Reactivity trends of the prepared complexes in the presence of the inserted hydrophobic salts such as tetrabutylammonium bromide (TBAB), tetraethylammonium bromide (TEAB), and tetramethylammonium bromide (TMAB) or hydrophilic salt potassium bromide (KBr) were studied. The observed decrease in the rate constants with increasing salt concentration was due to the cationic character of the reacting complexes. In addition, the synthesized compounds were tested for antimicrobial activity against selected strains of microbes. The results showed that the order of reactivity of the investigated complexes against the selected microbes were as follows: ppaqFe > paaqFe > pmaqFe. In addition, the investigated ligands and their Fe(II) complexes were screened for anticancer activities against several cell lines of cancer. The ppaqFe complex showed the best cytotoxic efficiency against the selected cancer lines (IC50 = 8.75–21.50 µg/µl), whereas the pmaq ligand showed the lowest cytotoxic efficiency (IC50 = 58.25– 72.40). Furthermore, the antioxidant potential of the presented compounds was studied by applying DPPH assays and showed a potential activity compared with standard vitamin C. The excellent antimicrobial and anticancer activities of the investigated Fe(II) chelates compared with literature values are promising and deserve further study.

Development of New Thiazole Complexes as Powerful Catalysts for Synthesis of Pyrazole-4-Carbonitrile Derivatives under Ultrasonic Irradiation Condition Supported by DFT Studies

In this study, we are interested in preparing Fe(III), Pd(II), and Cu(II) complexes from new thiazole derivatives. All syntheses were elaborately elucidated to estimate their molecular and structural formulae, which agreed with those of mononuclear complexes. The square-planer geometry of Pd(II) complex (MATYPd) was the starting point for its use as a heterocatalyst in preparing pyrazole-4-carbonitrile derivatives 4a-o using ultrasonic irradiation through a facile one-pot reaction. The simple operation, short-time reaction (20 min), and high efficiency (97%) were the special advantages of this protocol. Furthermore, this green synthesis strategy was advanced by examination of the reusability of the catalyst in four consecutive cycles without significant loss of catalytic activity. The new synthesis strategy presented remarkable advantages in terms of safety, simplicity, stability, mild conditions, short reaction time, excellent yields, and use of a H₂O solvent. This catalytic protocol was confirmed by the density functional theory (DFT) study, which reflected the specific characteristics of such a complex. Logical mechanisms have been suggested for the successfully exerted essential physical parameters that confirmed the superiority of the Pd(II) complex in the catalytic role. Optical band gap, electrophilicity, and electronegativity features, which are essential parameters for the catalytic behavior of the Pd(II) complex, are based mainly on the unsaturated valence shell of Pd(II).

Synthesis, spectral characterization, DFT calculations, pharmacological studies, CT-DNA binding and molecular docking of potential N, O-multidentate chelating ligand and its VO(II), Zn(II) and ZrO(II) chelates

The pharmacological efficacy of the variety tetradentate ligands encouraged us to design attractive compounds through effective synthetic procedure. The prepared Schiff base ligand 6,6'-((1E,1'E)-((4-chloro-1,2-phenylene)bis(azaneylylidene))bis(methaneylylidene))bis(2-ethoxy phenol (H₂L), which derived from 4-chloro-o-phenylenediamine and 3-ethoxy-salicylaldehyde and its VO(II), Zn(II) and ZrO(II) metal chelates, have been synthesized and characterized with aim of that it may struggle the invasion of drug resistance. The chemical structural of studied compounds were discussed by TGA, elemental analysis, UV-Vis., ¹H NMR, ¹³C NMR, FTIR, mass spectral, PXRD, molar conductance, magnetic susceptibility measurements and density functional theory. The results assigned square pyramid geometries for [VOL] and [ZrOL].2H₂O chelates and an octahedral geometry for [ZnL(H₂O)₂].2H₂O chelate. Powder XRD data showed that the complexes are monoclinic with polycrystalline nature. The results of CT-DNA interaction with the titled chelates showed that the binding between CT-DNA and the metal complexes occurs through intercalation mode. Their CT-DNA binding efficiency estimated in terms of their binding constants (K_b), which gave the order: VOL (6.9 × 10⁵) > ZrOL (6.3 × 10⁵) > ZnL(H₂O)₂ (5.5 × 10⁵). The antimicrobial activities of the synthesized compounds were tested against selected fungal and bacterial strains using well diffusion technique. The obtained chelates showed higher antifungal and antibacterial activities than their corresponding ligand. Furthermore, the M-complexes showed higher potent cytotoxic effect toward HEK-293, human colorectal HepG-2, HCT-116 and MCF-7 adenocarcinoma cell lines compared to the free H₂L ligand. Investigation of antioxidant property represented that all the prepared complexes have better radical scavenging potencies against DPPH radicals than the free H₂L ligand. To study the molecular docking of proposed compounds versus Tyrosine kinases receptor (TKR), we used AutoDock1.5.6rc3® suite. The current compounds (H₂L, VOL, ZrOL and ZnL(H₂O)₂) and STI were found to bind with C-kit of TKR with HBs at ILE789.A, ILE808.A, ASP810.A, GLU640.A and TYR846 amino acid residue and the binding energies were - 8.9, -8.93, -8.83, -1.48 and -10.39 kcal/mol respectively.