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Three new copper(II) and nickel(II) complexes, [Cu3L2(μ2-NO3)2(μ1,1-N3)2] (1), [Cu2L2(μ1,1-N3)2]n (2) and [Ni3L2(MeOH)2(μ2-η1:η1-CH3COO)2(μ2-η2:η0-CH3COO)2] (3), where L = 5-bromo-2-((3-methylaminopropylimino)methyl)phenolate, have been synthesized and characterized. The complexes were characterized by elemental analyses, IR, UV–Vis spectra, molar conductivity, and single crystal X-ray diffraction. X-Ray analysis indicates that the Cu ions in 1 are in square pyramidal and octahedral coordination, and the Cu ions in 2 and the Ni ions in 3 are in octahedral coordination. The molecules of the complexes are linked through hydrogen bonds and π···π interactions. The complexes were assayed for antibacterial activities against three Gram-positive bacterial strains (Bacillus subtilis, Staphylococcus aureus, and Streptococcus faecalis) and three Gram-negative bacterial strains (Escherichia coli, Pseudomonas aeruginosa, and Enterobacter cloacae) by the MTT method. [ABSTRACT FROM AUTHOR]

A series of copper(II) complexes, [CuCl 2 (HL 1 )]·CH 3 OH ( 1 ), [CuL 2 (ONO 2 )] ( 2 ), [CuBrL 2 ] ( 3 ) and [CuL 3 (NCS)(CH 3 OH)] ( 4 ) were prepared from 3,5-dihydroxy- N ′-(pyridin-2-ylmethylene)benzohydrazide (HL 1 ), 2-hydroxy- N ′-(1-(pyridin-2-yl)ethylidene)benzohydrazide (HL 2 ) and 4-methoxy- N ′-(pyridin-2-ylmethylene)benzohydrazide (HL 3 ). The compounds were characterized by physico-chemical methods. Structures of HL 1 and the complexes were further confirmed by single crystal X-ray diffraction. The metal atoms in complexes 1 and 4 display square pyramidal coordination, in complexes 2 and 3 display square planar coordination. The inhibitory effects of the compounds on Jack bean urease were evaluated. The results showed that the hydrazone HL 1 and complexes 1 and 4 have significant urease inhibitory activities, with IC 50 values of 8.2 ± 1.5, 6.3 ± 1.7, and 3.1 ± 1.2 μmol·L −1 , respectively. Complexes 2 and 3 show medium urease inhibitory activities, with IC 50 values of 35.7 ± 3.1, and 41.5 ± 2.7 μmol·L −1 , respectively. Molecular docking study of the compounds with Jack bean urease was performed to study the probable binding modes. The compounds with effective urease inhibitory activities anchor well in the active center of the urease and extend to the entrance of the binding pocket by interacting with its key amino acid residues. The results endorse that the hydrazone compound HL 1 and complexes 1 and 4 may serve as structural templates for the design and development of novel urease inhibitors. [ABSTRACT FROM AUTHOR]

Two new copper(II) complexes, [CuL(HL)]·ClO4 (1) and [Cu2Br2L2]·0.85H2O (2), where L is the monoanionic form of 4-tert-butyl-N′-(1-(pyridin-2-yl)ethylidene)benzohydrazide (HL), have been prepared. The complexes were characterized by infrared and UV–vis spectra, and single crystal X-ray diffraction. Complex 1 is a mononuclear copper(II) species and 2 is a bromido-bridged dinuclear copper(II) species. The Cu ion in 1 is in an octahedral coordination mode and that in 2 is trigonal-bipyramidal. The Jack bean urease inhibitory assay indicated that 2 is active, with IC50 value of 20.6 ± 2.3 μmol L−1, while 1 is inactive. Molecular docking of 2 with Jack bean urease was studied. [ABSTRACT FROM AUTHOR]

Two new mononuclear nickel(II) complexes, [NiL¹(NCS)] (1) and [Ni(L²)2]¢2NO3 (2), where L¹ is the deprotonated form of 1-[(2-ethylaminoethylimino)methyl]-naphthalen-2-ol, and L² is the zwitterionic form of 2,4-dibromo-6-[(2-ethylaminoethylimino)methyl]phenol, have been prepared and characterized by physicochemical methods and single-crystal X-ray diffraction. The Ni atoms in both complexes are in square planar coordination. The Ni atom in 1 is coordinated by one phenolate O, one imine N, and one amine N atom of L¹ ligand and one thiocyanate N atom. The Ni atom in 2 is coordinated by two phenolate O and two imine N atoms of two L² ligands. Crystals of the complexes are stabilized by hydrogen bonds. Thermal stability of the complexes has been studied. The Schiff bases and the complexes showed potent antibacterial activities. [ABSTRACT FROM AUTHOR]

A new hydrazone 4-bromo-N′-(2-hydroxy-5-methoxybenzylidene)benzohydrazide (HL) was prepared and characterized by infrared and UV–vis spectra, as well as single-crystal X-ray diffraction. With the hydrazone as ligand, two new copper(II) complexes were prepared, [Cu2L2(NCS)2]·4H2O (1) and [CuBrL]·CH3OH (2). The complexes were characterized by infrared and UV–vis spectra, and single-crystal X-ray diffraction. The Cu in1is in a square pyramidal coordination geometry and that in2is in a square planar coordination geometry. The two complexes show effectiveJack beanurease inhibitory activity, with IC50values of 23.5 and 2.7 μM, respectively. A molecular docking study of2with the urease was performed. The relationship between the structure and urease inhibitory activity indicated that copper complex with square planar coordination is a better model for urease inhibition. [ABSTRACT FROM AUTHOR]

Two vanadium(V) complexes, [VOL1L'] and [VOL2L']·0.5CH3OH, were prepared by the reaction of [VO(acac)2] (where acac = acetylacetonate) and benzohydroxamic acid (HL') withN'-(3-bromo-2-hydroxybenzylidene)-2-methylbenzohydrazide (H2L1) andN'-(3-bromo-2-hydroxybenzylidene)-2-methoxybenzohydrazide (H2L2), respectively, in methanol. Molecular component and structures of the complexes were determined by elemental analysis,1H NMR, IR and UV spectra. Single crystal structures of the complexes were determined by X-ray diffraction. The V atoms are in octahedral coordination. [ABSTRACT FROM PUBLISHER]

A new oxovanadium(V) complex, [N'-(3-ethoxy-2-hydroxybenzylidene)-4-fluorobenzohydrazido](quinolin-8-olato)oxovanadium(V), [VO(EFH)(QN)], where EFH is the anion ofN'-(3-ethoxy-2-hydroxybenzylidene)-4-fluorobenzohydrazide, and QN is the anion of 8-hydroxyquinoline, was prepared and characterized by elemental analysis, infrared spectra, thermal analysis and single-crystal X-ray diffraction. The complex crystallizes in the monoclinic space groupP21/n, with unit cell dimensionsa= 8.3921(4) Å,b= 28.200(1) Å,c= 10.0237(5) Å, β = 102.394(1)°,V= 2316.9(2) Å3,Z= 4, GOOF = 1.101,R1= 0.0464, andwR2= 0.1081. The V atom is coordinated by the three donor atoms of EFH and two donor atoms of QN, as well as one oxo oxygen group, forming an octahedral coordination. [ABSTRACT FROM AUTHOR]

Three cobalt(III), nickel(II), and manganese(III) complexes, [Co(L1)(N3)] (1), [Ni(L2)]·ClO4 (2), and [MnL3(NCS)(OH2)] (3), where L1, L2, and L3 are the deprotonated forms of 2,2′-[1,1′-(3-azapentane-1,5-diyldinitrilo)diethyl]diphenol (H2L1), 2-{1-[2-(2-aminoethylamino)ethylimino]ethyl}phenol (HL2), and N,N’-ethylene-bis(2-hydroxyacetophenoneimine) (HL3), respectively, have been prepared and structurally characterized by physicochemical methods and single-crystal X-ray diffraction. Even though the ligands in the complexes are different, they were prepared with the same starting material, viz. 2-acetylphenol and diethylenetriamine. The metal salts and pseudohalide ligands used in the preparation of the complexes can influence the types of the Schiff-base ligands. [ABSTRACT FROM AUTHOR]

Two new dioxovanadium(V) complexes, [VO2L1]2 (1) and [VO2L2] (2), where L1 and L2 are the deprotonated forms of 4-chloro-2-[(2-isopropylaminoethylimino)methyl]phenol and 4-chloro-2-[(2-morpholin-4-ylethylimino)methyl]phenol, respectively, have been synthesized and characterized by IR spectra and single crystal X-ray diffraction. Complex (1) is a centrosymmetric dinuclear dioxovanadium complex, with the V atom six-coordinate in an octahedral geometry. The V⋅⋅⋅V distance is 3.224(2) Å. Complex (2) is a mononuclear dioxovanadium complex, with the V atom five-coordinate in a distorted square pyramidal geometry. The steric effects of the terminal groups in the Schiff base ligands can influence the structures of the complexes. [ABSTRACT FROM AUTHOR]

A new acetohydroxamate coordinated oxidovanadium(V) complex derived from the pyridinohydrazone ligand 2′-(2-hydroxy-4-methoxybenzylidene)nicotinohydrazide (H 2 L), was prepared and characterized by elemental analysis, IR, UV–vis and 1H NMR spectra, and single crystal X-ray diffraction. Thermal analysis of the complex was performed. The V atom is in octahedral coordination. The complex has remarkable inhibitory activity on Jack bean urease with IC 50 value of 14.9 μmol·L−1. The interaction mode of the complex with the urease was studied by molecular docking technique. Unlabelled Image • A new acetohydroxamate coordinated oxidovanadium(V) complex was prepared. • The complex has been characterized by single crystal X-ray diffraction. • The complex shows strong urease inhibitory activity. [ABSTRACT FROM AUTHOR]

Two new maltolate- and ethylmaltolate-coordinated oxidovanadium(V) complexes with aroylhydrazone ligand were prepared. The aroylhydrazone and the complexes have been characterized by elemental analysis, IR, UV–Vis and NMR spectra. Single crystal structures of the aroylhydrazone and the complexes have been determined. The complexes have effective insulin-like activity on alloxan-diabetic mice. Two new oxidovanadium(V) complexes, [VOLL1] and [VOLL2], where L is the dianionic form of N ′-(3-ethoxy-2-hydroxybenzylidene)-3-methylbenzohydrazide (H 2 L), L1 is maltolatel, and L2 is ethylmaltolate, have been prepared. Both H 2 L and the complexes have been characterized by elemental analysis, IR, UV–Vis and NMR spectra. The structures of the compounds were further confirmed by single crystal X-ray diffraction. The aroylhydrazone ligand coordinates to the V atoms through the phenolate oxygen, imino nitrogen and enolate oxygen. The maltolate and ethylmaltolate ligands coordinated to the V atoms through the carbonyl oxygen and deprotonated hydroxyl oxygen. The V atom in each complex is in octahedral coordination. The complexes were administered intragastrically to both normal and alloxan-diabetic mice. The biological activity results show that the complexes at doses of 10.0 and 20.0 mg V·kg−1, can significantly decrease the blood glucose level in alloxan-diabetic mice, but the blood glucose level in the treated normal mice was not altered. [ABSTRACT FROM AUTHOR]

A series of new copper(II) complexes were prepared. They are [CuL 1 (NCS)] ( 1 ), [CuClL 1 ]·CH 3 OH ( 2 ), [CuClL 2 ]·CH 3 OH ( 3 ), [CuL 3 (NCS)]·CH 3 OH ( 4 ), [CuL 4 (NCS)]·0.4H 2 O ( 5 ), and [CuL 5 (bipy)] ( 6 ), where L 1 , L 2 , L 3 and L 4 are the deprotonated form of N ′-(2-hydroxybenzylidene)-3-methylbenzohydrazide, 4-bromo- N ′-(2-hydroxy-5-methoxybenzylidene)benzohydrazide, N ′-(2-hydroxy-5-methoxybenzylidene)-3-methylbenzohydrazide and 2-chloro- N ′-(2-hydroxy-5-methoxybenzylidene)benzohydrazide, respectively, L 5 is the dianionic form of N ′-(2-hydroxybenzylidene)-3-methylbenzohydrazide, and bipy is 2,2′-bipyridine. The complexes were characterized by infrared and UV–Vis spectra and single crystal X-ray diffraction. The Cu atoms in complexes 1 , 2 , 3 , 4 and 5 are coordinated by the NOO donor set of the aroylhydrazone ligands, and one Cl or thiocyanate N atom, forming square planar coordination. The Cu atom in complex 6 is in a square pyramidal coordination, with the NOO donor set of L 1 , and one N atom of bipy defining the basal plane, and with the other N atom of bipy occupying the apical position. Complexes 1 , 2 , 3 , 4 and 5 show effective urease inhibitory activities, with IC 50 values of 5.14, 0.20, 4.06, 5.52 and 0.26 μM, respectively. Complex 6 has very weak activity against urease, with IC 50 value over 100 μM. Molecular docking study of the complexes with the Helicobacter pylori urease was performed. The relationship between structures and urease inhibitory activities indicated that copper complexes with square planar coordination are better models for urease inhibition. [ABSTRACT FROM AUTHOR]

A new benzohydrazone compound N ′-(3-bromo-2-hydroxybenzylidene)-4-methoxybenzohydrazide (H 2 L) was prepared. Reaction of H 2 L and acetohydroxamic acid (HAHA) with VO(acac) 2 in methanol gave the complex [VOL(AHA)]. Both H 2 L and the oxovanadium complex were characterized by elemental analysis, IR, UV–vis and 1 H NMR spectra, and single crystal X-ray diffraction. H 2 L was also characterized by high-resolution mass spectrum. Thermal analysis of the oxovanadium complex was carried out. The benzohydrazone ligand, in its dianionic form, coordinates to V atom through the phenolate oxygen, imino nitrogen and enolate oxygen. The acetohydroxamic acid coordinates to V atom through the carbonyl oxygen and deprotonated hydroxyl oxygen. The V atom is in octahedral coordination. H 2 L, HAHA and the oxovanadium complex were tested for their urease inhibitory activities. The percent inhibition at concentration of 100 μmol·L −1 on Helicobacter pylori urease is 78% for the oxovanadium complex. The IC 50 value for the complex is 36.5 μmol·L −1 . Molecular docking study was performed to study the inhibition. [ABSTRACT FROM AUTHOR]