Ашық рұқсат
Рұқсат берілді
Тек жазылушылар үшін
Том 50, № 11 (2024)
Articles
Complexes of Hexacoordinated Ni(II) Based on Diacetyl bis-hetarylhydrazones: Structures and Magnetic Properties
Аннотация
Mononuclear nickel complexes [NiL1(NCS)2] ⋅ 2DMSO (I), [NiL1(NCS)2] ⋅ DMF (II), and [NiL2(NCS)2] ⋅ 0,5CH3OH ⋅ 1,5H2O (III) with the distorted octahedral coordination node, where L1 and L2 are the tetradentate ligand systems derived from the products of the condensation of diacetyl with 2-hydrazinoquinoline and 2-hydrazino-4,6-dimethylpyrimidine, respectively, are synthesized. The structures of the compounds are determined by IR pectroscopy and XRD (CIF files ССDС nos. 2219793 (I), 2142035 (II), and 2219794 (III)). The quantum chemical modeling of the axial parameter of magnetic anisotropy in the zero field (D) is performed for the synthesized compounds in the framework of the SA-CASSCF+NEVPT2 method. The complexes are shown to be characterized by three-axis magnetic anisotropy close to the light magnetization plane with positive D. The axial parameter of magnetic anisotropy (Dexp = 8.79 cm–1) determined by the approximation of the magnetometry data on complex [NiL2(NCS)2] ⋅ 0,5CH3OH ⋅ 1,5H2O is consistent with the calculated value (Dcalc = 11.5 cm–1).
739-752
Complexes R₂Sn(IV)L with Tridentate O,N,O΄-Donor Schiff Bases: Photophysical Properties and Biological Activity
Аннотация
New tin(IV) complexes (Ln)SnR2 (R = n-Bu (I, II), t-Bu (III–V), and Ph (VI)) with O,N,O΄-donor Schiff bases are synthesized. The molecular structures of compounds I and IV in the crystalline state are determined by XRD (CIF files CCDC nos. 2309864 (I) and 2309422 (IV)). The photophysical properties of the complexes are studied in comparison with the previously synthesized compounds containing phenyl or ethyl hydrocarbon groups at the tin atom. All compounds luminesce in chloroform: the emission bands are observed in the range from 580 to 638 nm. Both the groups at the tin atom and nature of the substituents in Schiff bases significantly affect the relative quantum yield. The anti/prooxidant activity of (Ln)SnR2 in the reactions with the ABTS (2,2΄-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)) radical cation and superoxide radical anion, in the oxidative DNA damage, and during lipid peroxidation in vitro is studied. A weak antibacterial activity against the bacterial strains Staphylococcus aureus ANCC 6538 and E. faecium ATCC 3576 are observed for some compounds. The in vitro antiproliferative properties for a number of the complexes are studied for the HTC-116 and А-549 cancer cell lines. The coordination of the organometallic fragment with the O,N,O΄-tridentate ligands is found to induce a pronounced decrease in the cytotoxicity of the complexes.
753-772
Coordination Compounds of 3d Metals with 2,4-Dimethylpyrazolo[1,5-а]benzimidazole: Magnetic and Biological Properties
Аннотация
New coordination compounds of copper(I), copper(II), cobalt(II), and nickel(II) with 2,4-dimethylpyrazolo[1,5-а]benzimidazole (L) were synthesized and studied. The complexes [CuLCl] (I), [CuLBr] (II), [CuL2Cl2] (III), [CuL2(NO3)2] · H2O (IV), [CoL2Cl2] · 0,5H2O (V), [CoL2(NO3)2] · · 0,5H2O (VI), and [NiL2(NO3)2] · 0,5H2O (VII) were studied by IR spectroscopy and powder and single crystal X-ray diffraction (CCDC nos. 2321779 ([CuL2Cl2]), 2321780 ([CoL2(NO3)2])). The results indicate that the coordination polyhedron in 2,4-dimethylpyrazolo[1,5-a]benzimidazole complexes is formed by the nitrogen atoms of the monodentate ligand and the coordinated anion. The cytotoxic and cytostatic properties of L and complexes I–III were studied in relation to the HepG2 hepatocellular carcinoma cells.
773-786
Imidazolium Salts with Heterometallic Complex Anions [Co₂Li₂(Piv)₈]²⁻: Synthesis, Structures, and Magnetic Properties
Аннотация
Imidazolium salts with complex anions [Co₂Li₂(Piv)₈]²⁻ are formed as undesirable products of the reactions of heterometallic compound [Co₂Li₂(Piv)₆(Py)₂] with N-heterocyclic carbenes ItBu and IPr. The study of the magnetic properties of complex (HItBu)₂[Co₂Li₂(μ₂-Piv)₆(Ƙ¹-Piv)₂] shows that this compound is a single molecule magnet. Slow magnetic relaxation in the complex occurs due to a combination of the direct and Raman mechanisms.
787-798
Mechanism of the Formation of trans- and cis-Isomers of the bis (chelate) Pd(II) and Pt(II) Complexes Based on (N,O(S, Se))-Bidentate Azomethines. А Quantum-Chemical Study
Аннотация
The molecular structures and relative energies of trans- and cis-isomers of bis(chelate) complexes of Pd(II) and Pt(II) salicylal-, thiosalicylal-, and selenosalicylaldiiminates are calculated using the density functional theory. The role of the kinetic factor in the formation of the trans- and cis-isomers of the PdL2 and PtL2 complexes is studied in the framework of the model of the step-by-step formation of the bis(ligand) metal complexes ML2 (M++ + (L)– → (ML)+, (ML)+ + (L)–→ ML2). The competition of the trans- and cis-isomers of the PdL2 and PtL2 bis(chelate) azomethine complexes with the coordination nodes MN2O2, MN2S2, and MN2Se2 is shown to be determined by both the energy preference of one of possible configurations and activation barriers of the isomerization of the products formed in the first step of the interaction of the initial reagents.
799-806