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Pd(II) with the Schiff base ligand 2-Hydroxy-3-Methoxy Benzaldehyde-Thiosemicarbazone (HMBATSC) (L2) and 2-aminobenzothiazole (2-ABZ) (L1) was synthesized. The Schiff base ligand and the Palladium(II) complex were characterized by C.H.N.S, FT-IR, conductance studies, magnetic susceptibility, XRD, and TGA. From the elemental analysis and spectral data, the complex was proposed to have the formula [Pd(HMBATSC)(2-ABZ)H2O]. The interaction between the Pd(II) complex and DNA was examined through various methods, including UV–Vis spectroscopy, fluorescence techniques, and DNA viscosity titrations. The findings provided strong evidence that the interaction between the Pd(II) complex and DNA occurs through the intercalation mode. The analysis yielded the following values: a Stern–Volmer quenching constant (ksv) of 1.67 × 104 M−1, a quenching rate constant (kq) of 8.35 × 1011 M−1 s−1, a binding constant (kb) of 5.20 × 105 M−1, and a number of binding the sites (n) of 1.392. DFT studies suggest that the azole derivative may act as an electron donor through pyridine nitrogen, while the Schiff base ligand may act as an electron donor via oxygen and sulfur atoms. TDDFT calculations indicate that the intramolecular charge transfer from the Schiff base to Pd(II) is responsible for the complex’s fluorescence quenching. The powder X-ray diffraction data revealed that the complex is arranged in a monoclinic system. The resulting Pd(II) complex was investigated for its antimicrobial activity and demonstrated antibacterial efficiency. Interestingly, it showed potent activity against E. coli and E. niger that was found to be more powerful than that recorded for Neomycin.

In the present work, a combination of experimental and density functional theory (DFT) investigation of the (3+2) cycloaddition reactions of diazopropane with chalcone derivatives was reported. All calculations were performed using several DFT approaches (B3LYP, M06, M06-2X) and 6-311+G(d, p) basis set. Based on the NMR, MS analyses and IRC calculations, the pyrazole derivatives are the kinetic adducts over the oxadiazoles. The use of two equivalents of diazopropane leads to thermodynamical products. A molecular docking analysis was performed to investigate the efficiency of the obtained products against selected drug targets in anti-Alzheimer ligand-receptor interactions. We revealed that the ligands selected were bound mainly to the catalytic (CAS) and peripheral (PAS) anionic sites of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitors, respectively. The selected ligands 1, 3, 4 and P14 may act as the best inhibitors against Alzheimer’s disease (AD).

In this work, new samples of PVA-TiO2/Cu nanocomposites were prepared via the casting method. The prepared samples were examined using different analytical methods. An XRD analysis showed the semi-crystalline nature of the PVA polymer, as well as showing a decrease in the degree of the crystallinity of the PVA structure as a result of the addition of the mixed nanoparticles. TEM images indicate the spherical shape of the Cu NPs, with a size ranging from 2 to 22 nm, and the rectangular shape of the TiO2 NPs, with a size ranging from 5 to 25 nm. It was evident via FTIR measurements that there were interactions between the functional groups of the PVA and the TiO2/Cu NPs. The optical properties of the PVA nanocomposites were improved with an increase in the content of the TiO2/Cu nanoparticles, as shown via a UV/Vis analysis. DSC curves showed an improvement in the thermal stability of the PVA-TiO2/Cu nanocomposites after the embedding of the TiO2/Cu nanoparticles. It was evident using impedance spectroscopy that the AC conductivity was improved by adding the TiO2 and Cu nanoparticles to the polymeric matrix. The maximum AC conductivity was found at 1.60 wt.% of TiO2/Cu nanoparticles in the PVA polymer, and this was 13.80 × 10−6 S/cm at room temperature. Relaxation occurred as a result of the charge carrier hopping between the localized state and the correlated barriers hopping model, describing the dominant mechanism, as presented in an electrical modulus analysis. These results indicate that the PVA-TiO2/Cu nanocomposite samples can be used in energy storage capacitor applications and in the alternative separator-rechargeable lithium-ion battery industry.

In this work, a three-component reaction of 3-acetyl-4-hydroxycoumarine, malononitrile, or cyanoacetate in the presence of ammonium acetate was used to form coumarin derivatives. The chemical structures of new compounds were identified by 1H, 13C NMR and an elemental analysis. These compounds were examined in vitro for their antimicrobial activity against a panel of bacterial strains. In addition, these compounds were investigated for antioxidant activities by superoxideradical, DPPH (2,2-Diphenyl-1-picrylhydrazyl), and hydroxyl radical scavenging assays, in which most of them displayed significant antioxidant activities. Furthermore, these compounds were evaluated for anti-inflammatory activity by indirect hemolytic and lipoxygenase inhibition assays and revealed good activity. In addition, screening of the selected compounds 2–4 against colon carcinoma cell lines (HCT-116) and hepatocellular carcinoma cell lines (HepG-2) showed that that 2-amino-4-hydroxy-6-(4-hydroxy-2-oxo-2H-chromen-3-yl)nicotinonitrile 4 exhibited good cytotoxic activity against standard Vinblastine, while the other compounds exhibited moderate cytotoxic activity. Docking simulation showed that2-amino-4-hydroxy-6-(4-hydroxy-2-oxo-2H-chromen-3-yl)nicotinonitrile 4 is an effective inhibitor of the tumor protein HCT-116. A large fluorescence enhancement in a highly acidic medium was observed, and large fluorescence quenching by the addition of traces of Cu2+ and Ni2+ was also remarked.