Excess properties calculated from literature values of experimental density and viscosity in N,N-dimethylacetamide + methanol binary mixtures (from 303.15 K to 318.15 K) can lead us to test different correlation equations as well as their corresponding relative functions. Inspection of the Arrhenius activation energy Ea and the enthalpy of activation of viscous flow ΔH* shows very close values, here we can define partial molar activation energy Ea₁ and Ea₂ for N,N-dimethylacetamide and methanol, respectively, along with their individual contribution separately. Correlation between the two Arrhenius parameters of viscosity in all compositions shows existence of main distinct behaviours separated by particular mole fractions in N,N-dimethylacetamide. In addition, we add that correlation between Arrhenius parameters reveals interesting Arrhenius temperature that is closely related to the vapourisation temperature in the liquid vapour equilibrium and the limiting corresponding partial molar properties can permit us to estimate the boiling points of the pure components.

A new chlorobenzylidene imine ligand, (E)-1-((5-chloro-2-hydroxybenzylidene)amino) naphthalen-2-ol (HL), and its [Zn(L)(NO₃)(H₂O)₃], [La(L)(NO₃)₂(H₂O)₂], [VO(L)(OC₂H₅)(H₂O)₂], [Cu(L)(NO₃)(H₂O)₃], and [Cr(L)(NO₃)₂(H₂O)₂], complexes were synthesized and characterized. The characterization involved elemental analysis, FT-IR, UV/Vis, NMR, mass spectra, molar conductance, and magnetic susceptibility measurements. The obtained data confirmed the octahedral geometrical structures of all metal complexes, while the [VO(L)(OC₂H₅)(H₂O)₂] complex exhibited a distorted square pyramidal structure. The complexes were found to be thermally stable based on their kinetic parameters determined using the Coats–Redfern method. The DFT/B3LYP technique was employed to calculate the optimized structures, energy gaps, and other important theoretical descriptors of the complexes. In vitro antibacterial assays were conducted to evaluate the complexes’ potential against pathogenic bacteria and fungi, comparing them to the free ligand. The compounds exhibited excellent fungicidal activity against Candida albicans ATCC: 10231 (C. albicans) and Aspergillus negar ATCC: 16404 (A. negar), with inhibition zones of HL, [Zn(L)(NO₃)(H₂O)₃], and [La(L)(NO₃)₂(H₂O)₂] three times higher than that of the Nystatin antibiotic. The DNA binding affinity of the metal complexes and their ligand was investigated using UV-visible, viscosity, and gel electrophoresis methods, suggesting an intercalative binding mode. The absorption studies yielded K_b values ranging from 4.40 × 10⁵ to 7.30 × 10⁵ M⁻¹, indicating high binding strength to DNA comparable to ethidium bromide (value 10⁷ M⁻¹). Additionally, the antioxidant activity of all complexes was measured and compared to vitamin C. The anti-inflammatory efficacy of the ligand and its metal complexes was evaluated, revealing that [Cu(L)(NO₃)(H₂O)₃] exhibited the most effective activity compared to ibuprofen. Molecular docking studies were conducted to explore the binding nature and affinity of the synthesized compounds with the receptor of Candida albicans oxidoreductase/oxidoreductase INHIBITOR (PDB ID: 5V5Z). Overall, the combined findings of this work demonstrate the potential of these new compounds as efficient fungicidal and anti-inflammatory agents. Furthermore, the photocatalytic effect of the Cu(II) Schiff base complex/GO was examined.

A new H₂L ligand (6, 6′-(pyridine-2, 6-diylbis(azan-1-yl-1-ylidene))bis(methan-1-yl-1-ylidene)bis(2-ethoxyphenol) was obtained from the reaction of 2, 6- diamino pyridine and 3- ethoxy salicyaldehyde in 1:2 molar ratio and fully characterized using elemental analyses and spectroscopic tools. The reaction of a ligand with the different metal salts yields five new complexes CuL, CoL, NiL, FeL, and VOL. The new complexes were identified according to the results of elemental analyses, IR and UV–vis spectra, magnetic moment, molar conductance and thermal analyses (TGA). From the conductivity data, it is deduced that all complexes are non-electrolytes. FT-IR spectra displayed that the Schiff base ligand coordinated to the metal ions in a manner with ONNO donor sites, the nitrogen atom of the pyridine ring, the nitrogen of one azomethine group and two oxygen atoms of the two phenolic OH groups. The results of electronic spectra and magnetic susceptibility confirmed octahedral geometry of FeL complex and square pyramidal geometry for CoL, CuL and VOL and square planar for NiL. The electronic structure of H₂L ligand and its complexes were investigated theoretically at the DFT-B3LYP-311 G** level of the theory. FT-IR spectra established the involvement of pyridine nitrogen in the coordination process. The presence of coordinated water molecules inside the coordination sphere of the complexes CoL, CuL and FeL are supported by TGA studies. The antimicrobial activities of the ligand and its complexes were determined against two Gram-positive bacteria (B. subtitles and S. aureus) and two Gram-negative (E. coli and P. vulgaris) and two fungus (Candida albicans and Aspergilla’s fumigates). The results showed that the complexes behaved as better antimicrobial agents than the ligand, VOL complex shows exceptional antimicrobial efficacy. The order of increasing the antibacterial and antifungal potency is H₂L < NiL < CuL < CoL < FeL < VOL. The binding of the complexes with CT-DNA was followed using electronic absorption, viscosity and gel-electrophoresis measurements. These studies confirmed that the complexes bind to CT-DNA through a groove binding mode with certain affinities (Kb = 6.25 × 10⁵, 5.50 × 10⁵, 3.20 × 10⁵, 2.50 × 10⁵ and 1.52 × 10⁵ for CuL, FeL, VOL, NiL, and CoL respectively). Moreover, cytotoxic effect against hepatocellular carcinoma cell line (HEP-G2) was screened. The IC₅₀ values of the ligand and complexes suggest that the compounds possess very good cytotoxic activity and follow the order: CuL _>FeL_>VOL_>NiL_>CoL > H₂L. These results strongly agree with results of binding constant of CT-DNA with different metal complexes.

Mixed ligand complexes of Ag(I) with triphenylphosphine (PPh₃), triphenylphosphine sulfide (SPPh₃), triphenylphosphine selenide (SePPh₃) and Imidazolidine‐2‐thione (Imt) have been prepared. The solution as well as solid state NMR studies have been carried out to characterize these complexes. Both solid and solution NMR show the coordination via thione group on one side and (S/Se) or PPh₃ on the other side. A higher antimicrobial activity is shown by [ImtAgPPh₃]Cl complex against gram negative Pseudomonas aeruginosa (P. aeruginosa) and Escherichia coli (E. coli) compared to the other two complexes i.e. [ImtAgSPPh₃]Cl and [ImtAgSePPh₃]Cl.

Calculation of excess properties in N,N-dimethylacetamide + 2-methoxyethanol binary mixtures at (298.15, 308.15 and 318.15) K from experimental density, viscosity and sound velocity values were presented in previous work. Applications of these experimental values to test different correlation equations as well as their corresponding relative functions were also reported. Considering the quasi-equality between the Arrhenius activation energy Ea and the enthalpy of activation of viscous flow ΔH*, here we can define partial molar activation energy Ea₁ and Ea₂ for N,N-dimethylacetamide and 2-methoxyethanol, respectively, along with their individual contribution separately. Correlation between Arrhenius parameters reveals interesting Arrhenius temperature with a comparison to the vaporisation temperature in the liquid vapour equilibrium, and the limiting corresponding partial molar properties that can permit us to estimate the boiling points of the pure components.