25 research outputs found
Toward multifunctional materials incorporating stepladder manganese(III) inverse-[9-MC-3]-Metallacrowns and anti-inflammatory drugs
The interaction of Mn(ClO4)2·6H2O with salicylaldoxime (H2sao) in the presence of nonsteroidal anti-inflammatory drug (NSAID) sodium diclofenac (Nadicl) or indomethacin (Hindo) leads to the formation of the hexanuclear Mn(III) clusters [Mn6(O)2(dicl)2(sao)6(CH3OH)6] (1) and [Mn6(O)2(indo)2(sao)6(H2O)4] (2) both characterized as stepladder inverse-9-metallacrown-3 accommodating dicl- or indo- ligands, respectively. When the interaction of MnCl2·4H2O with Nadicl or Hindo is in the absence of H2sao, the mononuclear Mn(II) complexes [Mn(dicl)2(CH3OH)4] (3) and [Mn(indo)2(CH3OH)4] (4) were isolated. The complexes were characterized by physicochemical and spectroscopic techniques, and the structure of complexes 1 and 2 was characterized by X-ray crystallography. Magnetic measurements (dc and ac) were carried out in order to investigate the nature of magnetic interactions between the magnetic ions and the overall magnetic behavior of the complexes
Supplementary material for the article: Ristovic, M. S.; Zianna, A.; Psomas, G.; Hatzidimitriou, A. G.; Coutouli-Argyropoulou, E.; Lalia-Kantouri, M. Interaction of Dinuclear Cadmium(II) 5-Cl-Salicylaldehyde Complexes with Calf-Thymus DNA. Materials Science and Engineering C 2016, 61, 579–590. https://doi.org/10.1016/j.msec.2015.12.054
Supplementary material: [https://doi.org/10.1016/j.msec.2015.12.054]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2052
Supplementary material for the article: Ristovic, M. S.; Zianna, A.; Psomas, G.; Hatzidimitriou, A. G.; Coutouli-Argyropoulou, E.; Lalia-Kantouri, M. Interaction of Dinuclear Cadmium(II) 5-Cl-Salicylaldehyde Complexes with Calf-Thymus DNA. Materials Science and Engineering C 2016, 61, 579–590. https://doi.org/10.1016/j.msec.2015.12.054
Supplementary material: [https://doi.org/10.1016/j.msec.2015.12.054]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2052
Unravelling the mechanism of water sensing by the Mg2+ dihydroxy-terephthalate MOF (AEMOF-1 ‘)
In this contribution we build upon our previous work on the MOF
[Mg(H(2)dhtp)(H2O)(2)]center dot DMAc (AEMOF-1 center dot DMAc) and
its activated dry version AEMOF-1 ‘ which has been shown to exhibit
excellent luminescence sensing properties towards water in organic
solvents. We demonstrate through combined structural and photophysical
studies that the observed changes in the fluorescence properties of
AEMOF-1 ‘ upon hydration arise from a structural transformation to the
mononuclear complex [Mg(H(2)dhtp)(H2O)(5)]center dot H2O (H(4)dhtp =
2,5-dihydroxyterepthalic acid) (1). In the latter complex, excited state
intramolecular proton transfer (ESIPT) is strongly favoured thereby
leading to enhanced and red shifted emission in comparison to AEMOF-1
center dot DMAc. Powder X-ray diffraction measurements confirmed that
complex 1 is identical to the hydrated form of AEMOF-1 center dot DMAc.
As in the case of AEMOF-1 ‘, the dry form of complex 1 (1 ‘) is also an
effective sensor for the determination of traces of water in
tetrahydrofuran (THF). This work demonstrates that the same chromophore
may exhibit very different emission properties when it exists in
different chemical environments and that these transformations may be
controlled and utilized in water sensing applications
Copper(II) Complexes of 5–Fluoro–Salicylaldehyde: Synthesis, Characterization, Antioxidant Properties, Interaction with DNA and Serum Albumins
The synthesis, characterization and biological profile (antioxidant capacity, interaction with calf-thymus DNA and serum albumins) of five neutral copper(II) complexes of 5–fluoro–salicylaldehyde in the absence or presence of the N,N’–donor co–ligands 2,2′–bipyridylamine, 2,9–dimethyl–1,10–phenanthroline, 1,10–phenanthroline and 2,2′–bipyridine are presented herein. The compounds were characterized by physicochemical and spectroscopic techniques. The crystal structures of four complexes were determined by single-crystal X-ray crystallography. The ability of the complexes to scavenge 1,1–diphenyl–picrylhydrazyl and 2,2′–azinobis(3–ethylbenzothiazoline–6–sulfonic acid) radicals and to reduce H2O2 was investigated in order to evaluate their antioxidant activity. The interaction of the compounds with calf-thymus DNA possibly takes place via intercalation as suggested by UV–vis spectroscopy and DNA–viscosity titration studies and via competitive studies with ethidium bromide. The affinity of the complexes with bovine and human serum albumins was examined by fluorescence emission spectroscopy revealing the tight and reversible binding of the complexes with the albumins
Iron(III) Complexes with Non-Steroidal Anti-Inflammatory Drugs: Structure, Antioxidant and Anticholinergic Activity, and Interaction with Biomolecules
One the main research goals of bioinorganic chemists is the synthesis of novel coordination compounds possessing biological potency. Within this context, three novel iron(III) complexes with the non-steroidal anti-inflammatory drugs diflunisal and diclofenac in the presence or absence of the nitrogen donors 1,10-phenanthroline or pyridine were isolated and characterized by diverse techniques. The complexes were evaluated for their ability to scavenge in vitro free radicals such as hydroxyl, 1,1-diphenyl-2-picrylhydrazyl and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radicals, revealing their selective potency towards hydroxyl radicals. The in vitro inhibitory activity of the complexes towards the enzymes acetylcholinesterase and butyrylcholinesterase was evaluated, and their potential to achieve neuroprotection appeared promising. The interaction of the complexes with calf-thymus DNA was examined in vitro, revealing their ability to intercalate in-between DNA nucleobases. The affinity of the complexes for serum albumins was evaluated in vitro and revealed their tight and reversible binding
Neutral and cationic manganese(II)–diclofenac complexes: structure and biological evaluation
<div><p>The interaction of MnCl<sub>2</sub> with the non-steroidal anti-inflammatory drug sodium diclofenac in the presence of 2,2′-bipyridine and pyridine resulted in the formation of cationic and neutral mononuclear complexes [Mn(diclofenac)(2,2′-bipyridine)(H<sub>2</sub>O)<sub>2</sub>] (diclofenac) (<b>1</b>) and [Mn(diclofenac)<sub>2</sub>(pyridine)<sub>2</sub>(H<sub>2</sub>O)<sub>2</sub>] (<b>2</b>), respectively. The structure of <b>1</b> was characterized by X-ray crystallography. In a preliminary attempt to evaluate the biological properties and possible application, the interaction of the complexes with calf-thymus DNA and human or bovine serum albumins was monitored. Additionally, the ability of the compounds to scavenge radicals such as 1,1-diphenyl-picrylhydrazyl, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), and hydroxyl radicals was evaluated; the complexes were more potent scavengers than free sodium diclofenac.</p></div
Palladium(II) Complexes of Substituted Salicylaldehydes: Synthesis, Characterization and Investigation of Their Biological Profile
Five palladium(II) complexes of substituted salicylaldehydes (X-saloH, X = 4-Et2N (for 1), 3,5-diBr (for 2), 3,5-diCl (for 3), 5-F (for 4) or 4-OMe (for 5)) bearing the general formula [Pd(X-salo)2] were synthesized and structurally characterized. The crystal structure of complex [Pd(4-Et2N-salo)2] was determined by single-crystal X-ray crystallography. The complexes can scavenge 1,1-diphenyl-picrylhydrazyl and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radicals and reduce H2O2. They are active against two Gram-positive (Staphylococcus aureus and Bacillus subtilis) and two Gram-negative (Escherichia coli and Xanthomonas campestris) bacterial strains. The complexes interact strongly with calf-thymus DNA via intercalation, as deduced by diverse techniques and via the determination of their binding constants. Complexes interact reversibly with bovine and human serum albumin. Complementary insights into their possible mechanisms of bioactivity at the molecular level were provided by molecular docking calculations, exploring in silico their ability to bind to calf-thymus DNA, Escherichia coli and Staphylococcus aureus DNA-gyrase, 5-lipoxygenase, and membrane transport lipid protein 5-lipoxygenase-activating protein, contributing to the understanding of the role complexes 1–5 can play both as antioxidant and antibacterial agents. Furthermore, in silico predictive tools have been employed to study the chemical reactivity, molecular properties and drug-likeness of the complexes, and also the drug-induced changes of gene expression profile (as protein- and mRNA-based prediction results), the sites of metabolism, the substrate/metabolite specificity, the cytotoxicity for cancer and non-cancer cell lines, the acute rat toxicity, the rodent organ-specific carcinogenicity, the anti-target interaction profiles, the environmental ecotoxicity, and finally the activity spectra profile of the compounds
Interaction of dinuclear cadmium(II) 5-Cl-salicylaldehyde complexes with calf-thymus DNA
Five dinuclear Cd(II) complexes with the anion of 5-Cl-salicylaldehyde (5-Cl-saloH) were synthesized in the absence or presence of the alpha-diimines: 2,2'-bipyridine (bipy), 1,10-phenanthroline (phen), 2,9-dimethyl-1,10-henanthroline (neoc) or 2,2'-dipyridylamine (dpamH) and characterized as [Cd(5-Cl-salo)(2)(CH3OH)](2) (1), [Cd(5-Cl-salo)(2)(bipy)](2) (2), [Cd(5-Cl-salo)(2)(phen)](2) (3), [Cd(5-Cl-salo)(neoc)(ONO2)](2) (4) and [Cd(5-Cl-salo)(dpamH)(ONO2)](2) (5). The complexes were characterized by spectroscopic techniques (IR, UV-vis, H-1-NMR and C-13-NMR), elemental analysis and molar conductivity measurements. The structures of four complexes (1-3 and 5) were determined by X-ray crystallography, providing all three possible coordination modes of the ligand 5-Cl-salicylaldehyde, i.e. bidentate or tridentate chelating and/or bridging mode. The complexes bind to calf-thymus (Cr) DNA mainly by intercalation, as concluded by the viscosity measurements and present relatively high DNA-binding constants. The complexes exhibit significant ability to displace ethidium bromide (EB) from the EB-DNA complex, thus indirectly proving the intercalation as the most possible binding mode to Cr DNA. (C) 2016 Elsevier B.V. All rights reserved.Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3544
Two new alkaline earth metal organic frameworks with the diamino derivative of biphenyl-4,4 ‘-dicarboxylate as bridging ligand: Structures, fluorescence and quenching by gas phase aldehydes
Alkaline earth metal ion organic frameworks (AEMOFs) represent a
relatively underexplored subcategory of MOFs. Two new MOFs
[Ca-6(bpdc-(NH2)(2))(5)(mu(3)-HCO2)(2)(H2O)(2.5)(DMF)(0.5)]center dot
0.5H(2)O center dot 2.5DMF (1) and [Sr-4(bpdc-(NH2)(4))(
mu(2)-DMF)(2)(DMF)(1/3)]center dot 2/3(DMF) (2) [H(2)bpdc-(NH2)(2)=
2,2’-diamino-[1,1’-biphenyl]-4,4’dicarboxylic acid); DMF =
N,N-dimethylformamide] are presented here. These MOFs display structural
variety with diverse topologies and new structural features.
Luminescence studies revealed that both MOFs display ligand based
fluorescence with small differences in emission profiles possibly
attributable to the difference in charge density of the metal ions
combined with the different conformation adopted by the ligand in the
crystal structures of 1 and 2. Furthermore, initial sensing studies
reveal that both MOFs can potentially function as fluorescent sensors
for gas phase aldehydes. (C) 2018 Elsevier Ltd. All rights reserved