| 1. |
- Durigon, Daniele C., et al.
(författare)
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The influence of thioether-substituted ligands in dicopper(II) complexes : Enhancing oxidation and biological activities
- 2024
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Ingår i: Journal of Inorganic Biochemistry. - 0162-0134. ; 256
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Tidskriftsartikel (refereegranskat)abstract
- This paper describes the synthesis, structural analysis, as well as the magnetic and spectroscopic characterizations of three new dicopper(II) complexes with dinucleating phenol-based ligands containing different thioether donor substituents: aromatic (1), aliphatic (2) or thiophene (3). Temperature-dependent magnetometry reveals the presence of antiferromagnetic coupling for 1 and 3 (J = −2.27 cm−1 and -5.01 cm−1, respectively, H = -2JS1S2) and ferromagnetic coupling for 2 (J = 5.72 cm−1). Broken symmetry DFT calculations attribute this behavior to a major contribution from the dz2 orbitals for 1 and 3, and from the dx2-y2 orbitals for 2, along with the p orbitals of the oxygens. The bioinspired catalytic activities of these complexes related to catechol oxidase were studied using 3,5-di-tert-butylcatechol as substrate. The order of catalytic rates for the substrate oxidation follows the trend 1 > 2 > 3 with kcat of (90.79 ± 2.90) × 10−3 for 1, (64.21 ± 0.99) × 10−3 for 2 and (14.20 ± 0.32) × 10−3 s−1 for 3. The complexes also cleave DNA through an oxidative mechanism with minor-groove preference, as indicated by experimental and molecular docking assays. Antimicrobial potential of these highly active complexes has shown that 3 inhibits both Staphylococcus aureus bacterium and Epidermophyton floccosum fungus. Notably, the complexes were found to be nontoxic to normal cells but exhibited cytotoxicity against epidermoid carcinoma cells, surpassing the activity of the metallodrug cisplatin. This research shows the multifaceted properties of these complexes, making them promising candidates for various applications in catalysis, nucleic acids research, and antimicrobial activities.
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| 2. |
- Maranha, Filipy Gobbo, et al.
(författare)
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A new heteropentanuclear complex containing the [Fe2 IIIZn3 II(μ-OH)3] structural motif as a model for purple acid phosphatases
- 2019
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Ingår i: Inorganica Chimica Acta. - : Elsevier BV. - 0020-1693.
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Tidskriftsartikel (refereegranskat)abstract
- Herein, we describe the synthesis and X-ray structure of a new heteropentanuclear complex (2) containing a [Fe2 IIIZn3 II(μ-OH)3] structural unit and the unsymmetrical ligand H2L2-et. The molecular structure of (2) shows that it is formed by a basic dinuclear [FeIII(μ-OH)ZnII(L2-et)] unit that is connected to a second dinuclear [FeIII(μ-OH)ZnII(L2-et)] unit through a hydroxo bridge while a third ZnII ion is coordinated by the pendant 1,2-ethanediamine groups of H2L2-et, resulting in the pentanuclear complex. Kinetic studies on the hydrolysis of the substrate 2,4-BDNPP (bis(2,4-dinitrophenyl)phosphate) reveal that (2) shows diesterase activity. While the kinetic activity is comparable to the corresponding dinuclear FeIIIZnII complex containing the same ligand, the association with 2,4-BDNPP is significantly decreased.
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