Moj Khaleghi

Combined experimental and theoretical studies on the X-ray crystal structure, FT-IR, 1H NMR, 13C NMR, UV-Vis spectra, NLO behavior and antimicrobial activity of 2-hydroxyacetophenone benzoylhydrazone.

A Schiff base ligand, 2-hydroxyacetophenone benzoylhydrazone (HL) was synthesized and fully characterized with FT-IR, elemental analyses, UV-Vis, (1)H NMR and (13)C NMR spectra. DFT calculations using B3LYP/6-31+G(d,p) and PW91/DZP are performed to optimize the molecular geometry. Optimized structures are used to calculate FT-IR, UV-Vis, (1)H NMR and (13)C NMR spectra of the compound. Also the energies of the frontier molecular orbitals (FMOs) have been determined. The results obtained from the optimization and spectral analyses are in good agreement with the experimental data. To investigate non-linear optical properties, the electric dipole moment (μ), polarizability (α) and molecular first hyperpolarizability (β) were computed. The linear polarizabilities and first hyperpolarizabilities of the studied molecule indicate that the compound can be a good candidate of nonlinear optical materials. In addition, the minimal inhibitory concentration (MIC) of this compound against Staphylococcus aureus, and Candida albicans was determined.

Synthesis, spectral characterization, structural studies, molecular docking and antimicrobial evaluation of new dioxidouranium(VI) complexes incorporating tetradentate N2O2 Schiff base ligands

Two new uranyl(VI) Schiff base complexes [UO2(L1)(DMSO)] (1), where L1 = N,N′-di(5-bromosalicylidene)-1,2-cyclohexyldiaminate ligand and [UO2(L2)(MeOH)] (2), where L2 = N,N′-di(5-bromosalicylidene)-o-phenylenediaminate ligand, were synthesized and characterized by elemental analysis, 1H NMR, FTIR, UV-vis, fluorescence spectroscopy and molar conductivity measurements. The structure of the H2L1 free ligand and both complexes (1) and (2) were also determined by single crystal X-ray diffraction. According to the results obtained, the title complexes have a distorted pentagonal bipyramidal geometry where positions around the U(VI) centre are occupied by the ONNO donors of the deprotonated dibasic Schiff base ligands (L1 for 1 and L2 for (2)), two oxido groups and the oxygen of coordinated solvent. The antimicrobial activity of ligands and complexes was also screened against Gram positive bacteria Staphylococcus aureus PTCC 1112, Micrococcus luteus PTCC 1110, Bacillus cereus PTCC 1015, Enterococcus faecalis; Gram negative bacteria Pseudomonas aeruginosa PTCC 1214, Escherichia coli PTCC1330, Pseudomonas sp., Klebsiella pneumoniae; and fungus strain (Candida albicans). The molecular docking of GlcN-6-P synthase with the synthesized compounds was also performed. According to the results, complex 2 displayed minimum binding energy and can be considered as a good antimicrobial agent.

Highly Stereoselective Synthesis of Saccharin-Substituted β-Lactams via in Situ Generation of a Heterosubstituted Ketene and a Zwitterionic Intermediate as Potential Antibacterial Agents

Highly stereoselective synthesis of saccharin derivatives containing functionalized 2-azetidinone moiety was achieved starting from saccharin as an available precursor. The approach to these valuable heterocyclic scaffolds involves a formal [2π + 2π] cycloaddition between Schiff bases and the saccharinylketene as a novel ketene which was generated in situ and an electrocyclic reaction of a zwitterionic intermediate. The identification of the ketene was confirmed by reaction with the stable free radical TEMPO (TO•). Also, the antimicrobial activities of some new substituted saccharin against nine standard bacteria, four bacteria which were isolated from clinical samples and one yeast, were evaluated.

A novel cationic cobalt(III) Schiff base complex: Preparation, crystal structure, Hirshfeld surface analysis, antimicrobial activities and molecular docking

A novel Co(III) complex, [Co(L)(Imi)3]Cl incorporating 2-((3-methoxy-2-oxidobenzylidene)amino)-4-methylphenolate (L2-), as a dibasic deprotonated Schiff base ligand and imidazole (Imi) was synthesized and fully characterized using physicochemical and spectroscopic techniques including elemental analysis, conductance measurement, FT-IR, UV-Vis and X-ray single crystal diffraction. As the conductivity data showed, the synthesized complex had a 1:1 ionic nature. The structure of the complex was found to be distorted octahedral in which, O/N donor atoms of the Schiff base ligand and N atoms of three imidazole groups were involved. Antimicrobial activity of the Co(III) complex as well as the its parent Schiff base ligand against two Gram-positive bacteria (S. Aureus and M. luteus), two Gram-negative bacteria (E. coli and P. aeruginosa) and a fungus (C. Albicans) was studied. Moreover, the antimicrobial activity of [Co(L)(Imi)3]Cl was investigated using molecular docking of the complex with GlcN-6-P synthase.

Synthesis of novel 1,8-dioxo octahydroacridine functionalized thioureas and thiazolidinones and evaluation of their antimicrobial activities

New series of thiourea and thiazolidinone derivatives containing a 1,8-dioxo octahydroacridinyl moiety have been synthesized through the reaction of 1-(4-Amino-phenyl)-3-methyl-thiourea with various aromatic aldehydes and dimedone. All the synthesized compounds were tested against several microbial pathogens Staphylococcus aureus, Micrococcus luteus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Candida albicans.

One-pot, three-component synthesis and in vitro antibacterial evaluation of novel 3-amino-N-benzyl-1-aryl-1H-benzo[f]chromene-2-carboxamide derivatives

A series of novel 3-amino-N-benzyl-1-aryl-1H-benzo[f]chromene-2-carboxamides have been synthesized by the reaction of N-benzyl-2-cyanoacetamide with 2-naphthol and aromatic aldehydes in the presence of piperidine as a base. The chemical structures of all the compounds were confirmed by spectroscopic methods as well as elemental analysis. In addition, the antibacterial activities of some target compounds against Gram-negative and Gram-positive bacteria in vitro were determined. Among these compounds, 4b, 4c, 4h and 4i exhibited antibacterial effects. The advantages of the present work reaction are clean reaction, metal-free transition, environmentally friendly approach to prepare different benzo[f]chromene-2-carboxamide derivatives, good yields, low cost, readily available starting materials and in addition does not need cumbersome procedure.