Syntheses, characterization, and antimicrobial properties of nickel(II) dithiocarbamate complexes containing NiS<sub>4</sub> and NiS<sub>2</sub>PN moieties

Novel nanosized Mn (II), Co (II), Cr (III) and Cu (II) complexes were synthesized with 2-((5-oxo-1,3-diphenyl-4,5-dihydro-1H-pyrazol-4-yl)diazenyl) benzoic acid, HL applying precipitation method. Their structures were characterized based on the elemental and thermal analyses, spectra (FT-IR, UV-Vis, MS, ESR and XRD), conductivity and magnetic moment measurements. IR spectra offered that HL behaves as monobasic tri-dentate ligand towards Mn (II), Cr (III) and Cu (II) and monobasic bi-dentate towards Co (II). The XRD results unambiguously confirmed the crystalline nature and nano-sized particles of Cu (II) complex while HL and other complexes exhibited amorphous phases.The magnetic moment data, UV-Vis and ESR spectra supported the formation of octahedral geometries for Mn (II), and Cr (III) complexes, whereas Co (II), and Cu (II) complexes showed tetrahedral arrangement. The activation parameters for the thermal degradation stages were theoretically calculated using TGA curves. The obtained data showed the inspected complexes as favorable antimicrobial drug candidates. The studied compounds were screened out for their antitumor and antimicrobial activities. The inspected compounds exhibited a reasonable antibacterial activity and weak antitumor efficacy. The in vitro results were confirmed using the in silico molecular docking analysis (docking server) applying x-ray crystallographic structures of the proteins (4 m01, 3 t88, 1zap & 4ynt) from PDB (Protein Data Bank). HL and probably its complexes displayed adequate binding with the receptors of 4 m01, 3 t88, 1zap, and 4ynt microorganisms. The obtained data show the inspected complexes as favorable antimicrobial drug candidates.

Section: Resultsmentioning

confidence: 73%

Nano‐synthesis, characterization, modeling and molecular docking analysis of Mn (II), Co (II), Cr (III) and Cu (II) complexes with azo pyrazolone ligand as new favorable antimicrobial and antitumor agents

Gaber

Khedr

Mansour

et al. 2018

“…The measured molar conductance values for the complexes lie within 6.80–12.70 ohm −1 cm 2 mol −1 range (Table ). These values indicate their non‐electrolytic nature …”

Section: Resultsmentioning

confidence: 93%

Characterization and thermal studies of nano‐synthesized Mn(II), Co(II), Ni(II) and Cu(II) complexes with adipohydrazone ligand as new promising antimicrobial and antitumor agents

Gaber

Khedr

Elsharkawy

2017

New seven complexes of N 1 ,N 6 -bis((2-hydroxynaphthalin-1-yl)methinyl)) adipohydrazone (H 2 L) with MnCl 2 •4H 2 O, CoCl 2 •6H 2 O, NiCl 2 •6H 2 O, CuCl 2 •2H 2 O, Cu(NO 3 ) 2 •3H 2 O, CuSO 4 •5H 2 O, and Cu(OAc) 2 •2H 2 O have beenprepared and characterized by the aid of elemental and thermal analyses, spectra (FT-IR, 1 H NMR, MS, UV-Vis, ESR, X-ray powder diffraction), molar conductance and magnetic moment measurements. The XRD results unambiguously confirmed the nano-sized particles of the complexes. The results showed that H 2 L behaves as dibasic tetra-dentate ligand towards the metal ions of interest. The low molar conductance values revealed the non-electrolytic nature for the chelates. The magnetic moment data, UV-Vis and ESR spectra denoted the formation of octahedral geometries for Mn(II) and Ni(II) complexes, whereas Co(II), Cu(II) complexes exhibited tetrahedral arrangement. The activation parameters for the thermal decomposition stages were calculated from TGA curves using Coats-Redfern and Horowitz-Metzger methods. The obtained data were confirmed by 3-D molecular modeling of the ligand and some complexes. The investigated compounds were screened for their antimicrobial activities against different types of organisms and antitumor activities towards human liver Carcinoma (HEPG2) cell to access their potential chemotherapeutic use. The free ligand (H 2 L) exhibited a weak inhibition of cell viability with IC 50 of 11.80 μg/ml, complexes 4, 6 and 7 showed a moderate activity with IC 50 of 5.56, 7.71 and 5.67 μg/ml, whereas complexes 1, 2, 3, and 5 displayed a strong anticancer activity with IC 50 of 4.65, 3.97, 3.30 and 4.84 μg/ml, compared with IC 50 value of 4.73 μg/ml for the doxorubicin (standard cytotoxin drug).

“…The visible region of the electronic spectrum of the nickel complex gave a band at 414 nm, due to 1 Ag → 1 Eg transition, which is characteristic of a square planar geometry. The assignment of this geometry was supported by the magnetic moment value of 0.14 BM, since a moment less than 1 BM is expected for nickel complex in a square planar environment . The visible spectrum of the cobalt complex gave a band at 405 nm, due to 4 A 2 → 4 T 1 (F) transitions, which is characteristic of a tetrahedral geometry.…”

Section: Resultsmentioning

confidence: 77%

Novel 3‐Hydroxy‐2‐naphthoic hydrazone and Ni(II), Co(II) and Cu(II) Complexes: Synthesis, Spectroscopic Characterization, Antimicrobial, DNA Cleavage and Computational Studies

Ekennia

Ibezim

Okpareke

et al. 2019

Self Cite

A novel hydrazone ligand derived from condensation reaction of 3-hydroxy-2naphthoic hydrazide with dehydroacetic acid, and its Ni(II), Cu(II) and Co(II) complexes were synthesized, characterized by spectroscopic, elemental analyses, magnetic susceptibility and conductivity methods, and screened for antimicrobial, DNA binding and cleavage properties. Spectroscopic analysis and elemental analyses indicated the formula, [MLCl 2 ], for the complexes; square planar geometry for the nickel, and tetrahedral geometry for copper and cobalt complexes. The non-electrolytic natures of the complexes in Dimethyl Sulphoxide (DMSO) were confirmed by their molar conductance values in the range of 6.11-14.01 Ω −1 cm 2 mol −1 . The copper complex had the best antibacterial activity against Staphylococcus aureus (ATCC 29213). DNA cleavage activities of the compounds, evaluated on pBR322 DNA, by agarose gel electrophoresis, in the presence and absence of oxidant (H 2 O 2 ) and free radical scavenger (DMSO), indicated no activity for the ligand, and moderate activity for the complexes, with the copper complex cleaving pBR322 DNA more efficiently in the presence of H 2 O 2 . When the complexes were evaluated for antibacterial and A-DNA activity using Molecular docking technique, the copper complex was found to be most effective against Gram-positive (S. aureus) bacteria. [CuLCl 2 ] showed good hydrogen bonding interaction with the major-groove (C 2 . G 13 base pair) of A-DNA. Density functional theory (DFT) calculations of the structural and electronic properties of the complexes revealed that [CuLCl 2 ] had a smaller HOMO-LUMO gap, suggesting a higher tendency to donate electrons to electron-accepting species of biological targets.