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A new mixed-ligand Cu(II) complex formulated as [Cu(dipic)(amp)(H 2 O)].H 2 O (dipic: pyridine-2,6-dicarboxylic acid, amp: 2-amino-4-methylpyridine), was synthesized and structurally characterized by FTIR spectroscopy, CHN analysis, and the single-crystal X-ray crystallographic method. The complex crystallizes in an orthorhombic space group Pna2 1, and the coordination environment around the metal center was found to be a pentacoordinate CuN 2 O 2 O W distorted square-pyramidal geometry. In order to systematically explore a detailed in vitro and in silico study of the DNA binding of the title complex, various biophysical (UV-Vis absorption spectroscopy, fluorescence, competitive binding with ethidium bromide) and theoretical (DFT, molecular docking simulation, and QM/MM) methods were applied which revealed that the complex could intercalate with the insertion of the amp ligand between the DNA base pairs. The experimental thermodynamic parameters of the interaction revealed the spontaneity of the process and the domination of the hydrophobic interactions in the association and stabilization of the DNA-Cu(II) complex adduct, which was in line with the docking and QM/MM data. In vitro cytotoxic potential of the complex against the human breast adenocarcinoma (MCF-7) cells was examined using MTT assay, which indicated that cancerous cells showed inhibition in presence of the complex., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

In this study, three new phospho thiadiazole compounds (A, F and W) were investigated as possible cytotoxic agents. The compounds were synthesised and characterised by using spectroscopy methods. The crystal structure of compound A was investigated using X-ray crystallography, since the title compounds can exist as different tautomeric forms, their conformational and geometrical aspects were investigated computationally by the DFT method. NBO analysis suggested that these compounds can function as appropriate ligands for the reaction with the nitrogen bases of DNA. All the synthesised compounds were evaluated in vitro for their cytotoxic activities against cancer in the human glioblastoma cell lines (U-251) using the MTT assay. According to the annexin V-FITC/PI results, a combination of synthesised compounds with ReoT3D showed a synergistic effect to increase the percentage of apoptotic cells. Molecular docking study for A (the most toxic compound) showed how it interacts with DNA. Both in vitro and in silico results showed that A has promising inhibitory potential (IC 50 : 48.1 ± 0.3 μM) and binding energy (-6.67 kcal/mol)., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Bacterial biofilms pose a serious medical problem due to their significant resistance to antimicrobials, and staphylococci are recognized as the most frequent cause of biofilm-associated infections. The hop plant (Humulus lupulus L.) contains substances that have been determined to act as anti-infective agents against bacteria, mainly in planktonic form. Therefore, we decided to investigate the antibiofilm properties of H. lupulus L.-derived compounds (humulone, lupulone and xanthohumol) against a selected group of Staphylococcus spp., including methicillin-susceptible and resistant strains. All tested hop compounds were shown to possess antimicrobial properties against all tested staphylococci, both planktonic and biofilm-dwelling, with no significant difference between resistant and susceptible strains. All compounds lowered the number of bacterial cells released from the biofilm, with the strongest effect seen for lupulone, followed by xanthohumol. Moreover, lupulone and xanthohumol were not only able to penetrate the biofilm and reduce the number of bacteria within it, but their higher concentrations (∼60 μg/mL for xanthohumol and ∼125 μg/mL for lupulone) reduced the number of surviving bacterial cells to zero., (Copyright © 2018 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.)

Two water-soluble mono-nuclear macrocyclic lanthanum(III) complexes of 2,6-diformyl-4-methylphenol with 1,3-diamino-2-propanol (C 1 ) or 1,3-propylenediamine (C 2 ) were synthesized and characterized by UV-Vis, FT-IR, 13 C and 1 H NMR spectroscopy and elemental analysis. C 1 complex was structurally characterized by single-crystal X-ray diffraction, which revealed that the complex was mononuclear and ten-coordinated. The coordination sites around lanthanum(III) were occupied with a five-dentate ligand, two bidentate nitrates, and one water molecule. The interaction of complexes with DNA was studied in buffered aqueous solution at pH7.4. UV-Vis absorption spectroscopy, emission spectroscopy, circular dichroism (CD) and viscometric measurements provided clear evidence of the intercalation mechanism of binding. The obtained intrinsic binding constants (K b ) 9.3×10 3 and 1.2×10 3 M -1 for C 1 and C 2 , respectively confirmed that C 1 is better intercalator than C 2 . The DNA docking studies suggested that the complexes bind with DNA in a groove binding mode with the binding affinity of C 1 >C 2 . Moreover, agarose gel electrophoresis study of the DNA-complex for both compounds revealed that the C 1 intercalation cause ethidium bromide replacement in a competitive manner which confirms the suggested mechanism of binding. Finally, the anticancer experiments for the treated cancerous cell lines with both synthesized compounds show that these hydrophilic molecules need a suitable carrier to pass through the hydrophobic nature of cell membrane efficiently., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Samarcandin 1, a natural sesquiterpene-coumarin, was isolated as well as elucidated from F. assa-foetida which has significant effect in Iranian traditional medicine because of its medicinal attitudes. The crystal structure of samarcandin was determined by single-crystal X-ray structure analysis. It is orthorhombic, with unit cell parameters a=10.8204 (5)Å, b=12.9894 (7)Å, c=15.2467 (9)Å, V=2142.9 (2)Å(3), space group P212121 and four symmetry equivalent molecules in the unit cell. Samarcandin was isolated in order to study for its theoretical studies as well as its cellular toxicity as anti-cancer drug against two cancerous cells. In comparison with controls, our microscopic and MTT assay data showed that samarcandin suppresses cancer cell proliferation in a dose-dependent manner with IC50=11μM and 13 for AGS and WEHI-164 cell lines, respectively. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) of the structure was computed by three functional methods and 6-311++G(∗∗) standard basis set. The optimized molecular geometry and theoretical analysis agree closely to that obtained from the single crystal X-ray crystallography. To sum up, the good correlations between experimental and theoretical studies by UV, NMR, and IR spectra were found., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Some new cadmium(II) Schiff base complexes CdLX2 (where X=Cl(-), Br(-), I(-), SCN(-) and N3(-) and L=N,N-bis((E)-3-(4-(dimethylamino)phenyl)allylidene)benzene-1,2-diamine) were synthesized and characterized by elemental analysis, FT-IR, UV-visible, (1)HNMR spectra, and conductivity measurements. Moreover, the structure of the CdLI2 was determined by single crystal X-ray crystallography. CdLI2 crystallizes in a triclinic system with space group P 1̅. The molecular structure shows distorted tetrahedral coordination geometry. The CH....π and π-π stacking interactions connect the molecules to a supramolecular network. The thermal properties of the compounds were investigated from the room temperature to 800 °C with a heating rate of 10 °C/min and decomposition activation parameters were evaluated from the TG/DTG plots. Antibacterial/antifungal activities of the compounds were screened by the disk diffusion method against the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa, the Gram-positive bacteria Staphylococcus aureus and Bacillus subtilis and the fungi strain Aspergillus niger and Candida albicans. The antimicrobial activities were determined for all compounds and the complexation was found to enhance the inhibitory activity. Finally, the DNA cleavage potential of the compounds was investigated by agarose gel electrophoresis method., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The crystal structures of two Schiff base compounds, 2,6-dichlorobenzylidene-2,4-dichloroaniline (1) and 2,4-dichlorobenzylidene-2,4-dichloroaniline (2) have been determined from single-crystal X-ray diffraction and characterized by FT-IR and (1)H NMR spectroscopy. The electronic structures of compounds 1 and 2 in the gas phase were computed by the density functional theory (DFT) method. The obtained theoretical results were supported by the crystallographic data. In addition, theoretical configurations of the title compounds were relaxed and studied in terms of the combined analysis of HOMO-LUMO energy gap, total density of states (DOS), molecular electrostatic potential (MEP), NMR spectra and harmonic vibrational frequencies., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Two new cadmium(II) complexes with the formula of CdL2(NCS)2 and CdL2(N3)2 (in which L is 2,2-dimethyl-N,N'-bis-(3-phenyl-allylidene)-propane-1,3-diamine) have been synthesized and characterized by elemental analysis, molar conductivity measurements, FT/IR, UV-Visible, (1)H and (13)C NMR spectra and X-ray studies. The crystal structure analysis of CdL2(NCS)2 indicated that it crystallizes in orthorhombic system with space group of Pbca. Two Schiff base ligands are bonded to cadmium(II) ion as N2-donor chelate. Coordination geometry around the cadmium ion was found to be partially distorted octahedron. The Cd-Nimine bond distances are found in the range of 2.363(2)-2.427(2)Å while the Cd-Nisothiocyanate bond distances are 2.287(2)Å and 2.310(2)Å. The existence of C-H⋯π and C-H⋯S interactions in the CdL2(NCS)2 crystal leads to a supramolecular structure in its network. Then cadmium complexes were screened in vitro for their antibacterial and antifungal activities against two Gram-negative and two Gram-positive bacteria and also against Candida albicans as a fungus. Moreover, the compounds were subjected for DNA-cleavage potential by gel electrophoresis method. Finally thermo-gravimetric analysis of the complexes was applied for thermal behavior studies and then some thermo-kinetics activation parameters were evaluated., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A series of new VO(IV) complexes of tetradentate N2O2 Schiff base ligands (L(1)-L(4)), were synthesized and characterized by FT-IR, UV-vis and elemental analysis. The structure of the complex VOL(1)⋅DMF was also investigated by X-ray crystallography which revealed a vanadyl center with distorted octahedral coordination where the 2-aza and 2-oxo coordinating sites of the ligand were perpendicular to the "-yl" oxygen. The electrochemical properties of the vanadyl complexes were investigated by cyclic voltammetry. A good correlation was observed between the oxidation potentials and the electron withdrawing character of the substituents on the Schiff base ligands, showing the following trend: MeO5-H>5-Br>5-Cl. Furthermore, the kinetic parameters of thermal decomposition were calculated by using the Coats-Redfern equation. According to the Coats-Redfern plots the kinetics of thermal decomposition of studied complexes is of the first-order in all stages, the free energy of activation for each following stage is larger than the previous one and the complexes have good thermal stability. The preparation of VOL(1)⋅DMF yielded also another compound, one kind of vanadium oxide [VO]X, with different habitus of crystals, (platelet instead of prisma) and without L(1) ligand, consisting of a V10O28 cage, diaminium moiety and dimethylamonium as a counter ions. Because its crystal structure was also new, we reported it along with the targeted complex., (Copyright © 2014 Elsevier B.V. All rights reserved.)

In this study isolation and structural elucidation of a homoisoflavonoid, 3-(3',4'-dihydroxybenzyl)-8-hydroxy-5,7-dimethoxychroman-4-one (Scillapersicone 1), is reported from Scilla persica HAUSSKN. The structure was solved by a single crystal X-ray analysis. The unit cell parameters are a=11.7676 (2)Å, b=20.1174 (4)Å, c=7.8645 (9)Å, β=93.544 (2)°, V=1858.23 (7)Å(3), monoclinic space group P21/c and four symmetry equivalent molecules in an unit cell. The structure was consistent with the UV, IR, 1D and 2D NMR, HRFAB-MS data. The optimized molecular geometry agrees closely that obtained from the single crystal X-ray crystallography. Furthermore, cytotoxicity of this compound was evaluated by MTT assay on AGS and WEHI-164 cancerous cell lines., (Copyright © 2014 Elsevier Inc. All rights reserved.)