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Four dinuclear bismuth(III) Schiff-base complexes bearing Schiff-base ligands have been synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analysis, and spectral techniques (FT-IR, NMR and MS). The analytical data reveal the bismuth(III) complexes possess 1:1 metal-ligand ratios. In vitro biological studies have revealed that bismuth(III) complexes displayed much higher antibacterial and antitumor activities than their parent ligands, which involves two gram-negative (S. aureus, B. subtili) and two gram-positive (E. coli, P. aeruginosa) bacteria, and human gastric cancer SNU-16 cells. The power-time curves of S. pombe exposed to tested compounds were detected by bio-microcalorimetry. Some thermokinetic parameters (k, P max, t G and Q total ) were derived based on the metabolic power-time curves, and their quantitative relationships with the concentrations (c) were further discussed., (Copyright © 2022 Elsevier Inc. All rights reserved.)

A new oxidovanadium(V) complex, [VOL(OEt)(EtOH)] (1), and a new dioxidomolybdenum(VI) complex, [MoO2L(OH2)] (2), where L is the dianionic form of 2-bromo-N'-(3,5-dichloro-2-hydroxybenzylidene)benzohydrazide, have been synthesized and structurally characterized by physico-chemical methods and single crystal X-ray determination. X-ray analysis indicates that the V and Mo ions in the complexes are in octahedral coordination. Crystal structures of the complexes are stabilized by hydrogen bonds. The catalytic property for epoxidation of styrene by the complexes was evaluated. Both complexes have effective catalytic properties for the epoxidation of styrene, with conversions over 76% and selectivities over 92%. [ABSTRACT FROM AUTHOR]

A new bismuth(III) Schiff‐base complex [Bi2(HL)2(NO3)4] was synthesized by using equivalent molar of Schiff‐base ligand [H2L = (E)‐N′‐(2‐hydroxy‐3‐methoxybenzylidene)isonicotinohydrazide] and Bi(NO3)3•5H2O with the assistance of Mannitol. The complex was structurally characterized by elemental analysis, spectroscopic methods, and single crystal X‐ray diffraction. The experimental and theoretical vibrational bands (infrared and Raman spectra) have been discussed. The antimicrobial activity of the complex against Schizosaccharomyces pombe was evaluated by bio‐microcalorimetry at 32°C. Some thermokinetic parameters (k, Pmax, tG, and Qtotal) were obtained from the metabolic power–time curves of S. pombe, and their quantitative relationships with the concentration (c) were discussed. The half inhibition concentrations (IC50) of isoniazid, Schiff base, and the complex were calculated. The complex showed the strongest inhibition effect among three compounds. [ABSTRACT FROM AUTHOR]

Reaction of the Schiff base 2,4-difuloro-6-(((2-(pyrrolidin-1-yl)ethyl)imino)methyl)phenol (HL) with copper salts and some bridging ligands afforded five complexes, [CuClL] (1), [Cu(μ-Br)L] n (2), [Cu(μ-Br)(μ 1,5 -dca)L] n ·nCH 3 OH (3), [Cu(μ 1,3,5 -dca)L] n (4) and [Cu(μ 1,3 -N 3)L] n (5) (dca = dicyanoamide). These complexes have been analyzed and characterized by the means of elemental analysis, infrared and electronic spectra, as well as single crystal X-ray diffraction. The Cu atom in the mononuclear complex 1 is in square planar coordination, in the bromido-bridged polynuclear complex 2 is in square pyramidal coordination, in the bromido and dca co-bridged polynuclear complex 3 is in square pyramidal coordination, in the dca bridged polynuclear complex 4 is in octahedral coordination, and in the azido bridged polynuclear complex 5 is in square pyramidal coordination. The Schiff base ligand coordinates to the CuII ions through the phenolate oxygen, imine nitrogen and pyrrolidine nitrogen atoms. The biological study revealed that the complexes have good antimicrobial activity against the bacteria strains B. subtilis , S. aureus , E. coli and P. fluorescens. [Display omitted] Reaction of the Schiff base 2,4-difluoro-6-(((2-(pyrrolidin-1-yl)ethyl)imino)methyl)phenol (HL) with copper salts and some bridging ligands afforded five complexes, [CuClL] (1), [Cu(μ-Br)L] n (2), [Cu(μ-Br)(μ 1,5 -dca)L] n ·nCH 3 OH (3), [Cu(μ 1,3,5 -dca)L] n (4) and [Cu(μ 1,3 -N 3)L] n (5) (dca = dicyanoamide). These complexes have been analyzed and characterized by the means of elemental analysis, infrared and electronic spectra, as well as single crystal X-ray diffraction. The Cu atom in the mononuclear complex 1 is in square planar coordination, in the bromido-bridged polynuclear complex 2 is in square pyramidal coordination, in the bromido and dca co-bridged polynuclear complex 3 is in square pyramidal coordination, in the dca bridged polynuclear complex 4 is in octahedral coordination, and in the azido bridged polynuclear complex 5 is in square pyramidal coordination. The Schiff base ligand coordinates to the CuII ions through the phenolate oxygen, imine nitrogen and pyrrolidine nitrogen atoms. The biological study revealed that the complexes have good antimicrobial activity against the bacteria strains B. subtilis , S. aureus , E. coli and P. fluorescens. [ABSTRACT FROM AUTHOR]

Reaction of silver nitrate with 2‐aminobenzothiazole (abbreviated as Habt) in methanol at 45°C gave mononuclear complex of formula [Ag (Habt)2]NO3•CH3OH. The structure of the complex was characterized by infrared (IR) spectra, single crystal X‐ray diffraction, and elemental analysis. X‐ray diffraction analysis indicated that the title complex was crystallized in the triclinic crystal system with space group P–1, in which silver(I) ion was coordinated to two 2‐aminobenzothiazole ligands through the benzothiazol nitrogen atom. Theoretical study of the complex was carried out by density functional theory (DFT) B3LYP method. The antimicrobial effects of the ligand and its silver(I) complex were evaluated by bio‐microcalorimetry on the growth of Schizosaccharomyces pombe (S. pombe). Some quantitative metabolic parameters, such as growth rate constant (k), maximum heat power (Pmax), inhibition ratio (I), and half inhibition concentration (IC50), were derived from the metabolic power–time curves of S. pombe growth. The half inhibition concentration (IC50) of the ligand was calculated to be 2.58 × 10−3 mol L−1. The complex could strongly influence the lag phase of S. pombe. [ABSTRACT FROM AUTHOR]

Five new copper(II), nickel(II) and zinc(II) complexes derived from 2-((2-(pyrrolidin-1-yl)ethylimino)methyl)phenol were synthesized and structurally characterized. Single crystal X-ray analysis indicates that the Cu atoms in the tetranuclear complexes 1 and 2 are in a square pyramidal coordination, the Ni atoms in the trinuclear complexes 3 and 4 are in an octahedral coordination and the Zn atom in the mononuclear complex 5 is in a tetrahedral coordination. In vitro bacterial viability revealed that the copper and zinc complexes have effective antimicrobial activity against B. subtilis , S. aureus , E. coli and P. fluorescens , and general activity against the fungal strains C. albicans and A. niger. [Display omitted] Five new copper(II), nickel(II) and zinc(II) complexes, [Cu 4 Cl 2 (μ 1,1 -N 3) 4 (DMF) 2 ] (1), [Cu 4 Br 2 (μ 1,1 -N 3) 4 (DMF) 2 ] (2), [Ni 3 L 2 (CH 3 COO) 4 ]CH 3 OH (3), [Ni 3 L 2 (CH 3 COO) 2 (μ 1,1 -N 3) 2 (CH 3 OH) 2 ] (4) and [Zn(LH)I 2 ]CH 3 OH (5), were designed and successfully synthesized using the Schiff base ligand 2-((2-(pyrrolidin-1-yl)ethylimino)methyl)phenol (HL). All the synthesized complexes were characterized using different physico-chemical and spectroscopic methods, like elemental analysis, infrared spectra and single crystal X-ray diffraction. The X-ray structural analysis showed that the Cu atoms in the tetranuclear complexes 1 and 2 are in a square pyramidal coordination, the Ni atoms in the trinuclear complexes 3 and 4 are in an octahedral coordination and the Zn atom in the mononuclear complex 5 is in a tetrahedral coordination. The Schiff base ligand was coordinated to the metal atoms through the phenolate oxygen, imino nitrogen and/or pyrrolidine nitrogen atoms. The biological study indicated that the copper and zinc complexes have interesting antimicrobial activity against B. subtilis , S. aureus , E. coli and P. fluorescens , with MIC values of 0.6–2.3 μmol/L. [ABSTRACT FROM AUTHOR]

Four new zinc(II) complexes derived from the bis-Schiff base ligand N,N' -bis(4-bromosalicylidene)-1,3-propanediamine have been synthesized and structurally characterized by elemental analysis, infrared spectra, as well as single crystal X-ray diffraction. X-ray analysis indicates that the Zn atoms in the complexes are in octahedral, tetrahedral and square pyramidal coordination. In vitro bacterial viability revealed that the complexes have effective antimicrobial activities against B. subtilis , S. aureus , E. coli and P. fluorescens. [Display omitted] A series of new zinc(II) complexes, [Zn 2 Cl 2 L(MeOH) 2 ] (1), [Zn 4 Cl 2 L 2 (N 3) 2 ] (2), [Zn 4 Br 2 L 2 (N 3) 2 ] (3) and [Zn 4 I 2 L 2 (N(CN) 2) 2 ] (4), where L is the dianionic form of N,N' -bis(4-bromosalicylidene)-1,3-propanediamine, have been synthesized and structurally characterized by elemental analysis, infrared spectra, as well as single crystal X-ray diffraction. X-ray analysis indicates that the Zn atoms in the dinuclear complex 1 are in octahedral and tetrahedral coordination, while in the tetranuclear complexes 2 , 3 and 4 are in square pyramidal and tetrahedral coordination. In vitro bacterial viability revealed that the complexes have effective antimicrobial activities against B. subtilis , S. aureus , E. coli and P. fluorescens , while weak activities against the fungal strains C. albicans and A. niger. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new cobalt(II) complex was synthesized and characterized. • Theoretical studies using DFT calculations. • The bioactivity of cobalt(II) complex was assessed by bio-microcalorimetry. • The complex displayed much stronger antibacterial activity than Schiff base. • Some thermokinetic parameters (k , P max , t G and Q total) were derived. A new cobalt(II) Schiff-base complex [Co(L) 2 ] was prepared by using equivalent molar of Schiff-base ligand [HL=(E)- N '-(2-hydroxy-3-methoxybenzylidene)isonicotinohydrazide] and CoCl 2 ·6H 2 O. The structure of the complex was characterized by single-crystal X-ray diffraction, IR, ESI-MS, elemental analysis and DFT method. X-ray crystal structure analysis showed that the complex crystallized in space group Pbca, with two symmetry-independent molecules. The experimental vibrational bands(IR) have been discussed and assigned based on DFT calculations. The antibacterial activity of Schiff base and its complex against S. pombe were assessed by bio-microcalorimetry at 32 °C. Some thermokinetic parameters (k , P max, t G and Q total) were derived from the metabolic power–time curves, and their quantitative relationship with the concentration were analyzed. The half inhibition concentration (IC 50) of Schiff base and its complex were calculated to be 1.18 × 10−2 mol L−1 and 1.07 × 10−3 mol L−1, respectively. The inhibition effect of the complex showed much stronger than that of Schiff base. [ABSTRACT FROM AUTHOR]