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A new vanadium(V) complex, [VOL(OMe)(MeOH)]·MeOH (1·MeOH), was prepared by the reaction of VO(acac)2 with 2-chloro-N'-(5-fluoro-2-hydroxybenzylidene)benzohydrazide (H2L) in methanol. By addition of salicylhydroxamic acid (HSHA) to the methanolic solution of 1, a new salicylhydroxamate-coordinated vanadium(V) complex, [VOL(SHA)]·H2O (2·H2O), was obtained. Both complexes were characterized by elemental analysis, infrared spectroscopy, thermal analysis and single crystal X-ray diffraction. Complex 1 crystallizes with methanol molecule as a solvate, and complex 2 as a monohydrate. The V atoms in the complexes are in octahedral coordination. In the crystal structure of 1·MeOH, the vanadium complexes are linked by methanol solvate molecules through intermolecular O–H∙∙∙N and O–H∙∙∙O hydrogen bonds to form chains along the c axis. In the crystal structure of 2·H2O, the vanadium complexes are linked by water molecules through intermolecular O–H∙∙∙O hydrogen bonds, to form 1D chains along the a axis. The chains are further linked through intermolecular O–H∙∙∙N and O–H∙∙∙O hydrogen bonds in the c direction to form 2D layers. The antimicrobial activities of the complexes against K. pneumoniae, S. aureus, P. aeroginosa, E. coli, and B. subtilis were investigated.

Two new oxidovanadium(V) complexes with the general formula [VOL(bha)], where L represents the deprotonated hydrazone ligands 2-hydroxy-N'-(4-methoxybenzylidene)naphthohydrazide (H2L1) for1andN'-(2-chlorobenzylidene)-2-hydroxynaphthohydrazide (H2L2) for2, and bha represents the monoanionic form of benzohydroxamic acid (Hbha), have been prepared and characterized by elemental analysis, infrared and UV-Vis spectra, and thermal behavior. Structures of the complexes have been further determined by single-crystal X-ray diffraction. The V atoms in the complexes are coordinated by the three donor atoms of the hydrazone ligands, the oxygen atoms of the benzohydroxamate ligands, and oxido oxygen atoms, constituting octahedral coordination spheres. [ABSTRACT FROM AUTHOR]

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]

A new copper(II) complex, [Cu(AA)(EDA)2] (1), and a new zinc(II) complex, [Zn(PA)2(EDA)] (2), where AA is 1-naphthylacetate, PA is 4-nitrophenylacetate, and EDA isN,N-dimethylethane-1,2-diamine, have been prepared and characterized. Structures of the complexes have been characterized by single-crystal X-ray diffraction. Complex1crystallizes as monoclinic space groupP21/n, with unit cell dimensionsa= 7.3327(4) Å,b= 24.031(1) Å,c= 13.9031(7) Å, β = 91.803(2)°, V = 2448.7(2) Å3, Z = 4,R1= 0.0487,wR2= 0.1199, S = 1.053. Complex2crystallizes as monoclinic space groupP21/c, with unit cell dimensionsa= 24.693(4) Å,b= 12.023(2) Å,c= 7.524(1) Å, β = 89.95(3)°, V = 2233.8(6) Å3, Z = 4,R1= 0.0696,wR2= 0.1845, S = 0.999. Complex1is a mononuclear copper(II) species, with the Cu atom coordinated in a square pyramidal geometry. Complex2is a mononuclear zinc complex, with the Zn atom coordinated in a tetrahedral geometry. Single crystals of the complexes are stabilized by hydrogen bonds and π…π interactions. [ABSTRACT FROM AUTHOR]

A new dinuclear bromido-coordinated Schiff base zinc(II) complex, [Zn2Br2L1(MeOH)]·MeOH (1), and a new mononuclear bromido-coordinated Schiff base zinc(II) complex, [ZnBr2L2] (2), where L1is the dianionic form ofN,N’-bis(5-fluoro-2-hydroxybenzylidene)propane-1,3-diamine (H2L1), and L2is the zwitterionic form of 2-[(3-dimethylammoniopropylimino)methyl]-4-fluorophenol, have been preprared and characterized mainly by single-crystal X-ray diffraction. Complex 1 crystallizes in the monoclinic space groupP21/nwith unit cell dimensionsa= 10.0876(9) Å,b= 8.9549(8) Å,c= 26.586(2) Å, β = 95.134(2)º, V = 2391.9(4) Ǻ3, Z = 4,R1= 0.0547, andwR2= 0.1025. Complex 2 crystallizes in the monoclinic space groupP21/cwith unit cell dimensionsa= 7.359(1) Å,b= 13.798(2) Å,c= 17.676(2) Å, β = 114.602(2)º, V = 1631.8(4) Ǻ3, Z = 4,R1= 0.0877, andwR2= 0.2197. The inner Zn atom in 1 is five-coordinated in a square pyramidal geometry. The outer Zn atom in 1 and the Zn atom in 2 are four-coordinated in tetrahedral geometry. The crystals of the complexes are stabilized by intermolecular hydrogen bonds. [ABSTRACT FROM PUBLISHER]

A μ-oxido-bridged dinuclear iron(III) complex, [Fe2O(L1)2(L2)2], where L1and L2are the deprotonated forms of 2,4-dichloro-6-[(2-morpholin-4-ylethylimino)methyl]phenol and 3,5-dichlorosalicylaldehyde, respectively, has been prepared and characterized by elemental analysis, infrared spectrum, and single-crystal X-ray determination. The complex crystallizes in the triclinic space groupP, with unit cell dimensionsa= 10.670(1) Å,b= 11.585(1) Å,c= 19.748(2) Å, α = 86.766(2)°, β = 85.038(2)°, γ = 73.973(2)°,V= 2336.1(4) Å3,Z= 2, GOOF = 1.019,R1= 0.0422, andwR2= 0.1024. Structural analysis shows that the iron atoms in the complex are hexacoordinate with a normal Fe-O-Fe bridging angle of 150.84(13)°. Each Fe atom is coordinated by the NNO donor atoms of L1, OO donor atoms of L2, and one bridging O atom. The Fe· · ·Fe distance is 3.467(2) Å. [ABSTRACT FROM PUBLISHER]

New oxidovanadium(V) complexes, [VOL1(bzh))]·H2O (1) and [VOL2(bzh))] (2), were prepared by the reaction of [VO(acac)2] (where acac?=?acetylacetonate) and benzohydroxamic acid (Hbzh) withN?-(5-bromo-2-hydroxybenzylidene)-3-methylbenzohydrazide (H2L1) andN?-(5-bromo-2-hydroxybenzylidene)-4-methylbenzohydrazide (H2L2), respectively, in methanol. Structures of the complexes were determined by elemental analysis, infrared and UV–vis spectra. Single crystal structures of the complexes were determined by X-ray diffraction. Vanadiums have octahedral coordination. Thermal stability and the inhibition of urease of the complexes were studied. [ABSTRACT FROM PUBLISHER]

Two new mononuclear Schiff base nickel(II) complexes, [Ni(ClSal)] (1) and [Ni(MeSal)] (2) (H2ClSal =N,N′-bis(3,5-dichlorosalicylidene)-1,3-pentanediamine; H2MeSal =N,N′-bis(3-methylsalicylidene)-1,2-ethanediamine), have been synthesized and characterized by elemental analyses, infrared spectra, and single-crystal X-ray diffraction. Complex 1 crystallizes in the orthorhombic space groupP212121, with unit cell dimensionsa= 9.788(1) Å,b= 10.206(1) Å,c= 20.458(2) Å,V= 2043.7(4) Å3,Z= 4,R1= 0.0814, andwR2= 0.1689. Complex 2 crystallizes in the monoclinic space groupP21/n, with unit cell dimensionsa= 11.6353(5) Å,b= 11.8807(6) Å,c= 12.8241(6) Å,β= 115.213(1)°,V= 1603.9(1) Å3,Z= 4,R1= 0.0243, andwR2= 0.0675. The Ni atoms in the complexes are four-coordinated in square planar geometry by the N2O2donor set of the ligands. [ABSTRACT FROM AUTHOR]

A pair of mononuclear Schiff base zinc(II) complexes, [ZnLCl2] (1) and [ZnLBr2] (2), have been prepared by the reaction of equimolar quantities of a new Schiff base ligand 2-[(2-dimethylammonioethylimino)methyl]-4-methylphenolate with ZnCl2and ZnBr2, respectively, in methanol. The structures of the complexes have been characterized by single-crystal X-ray diffraction. Complex 1 crystallizes as orthorhombic space groupP212121, with unit cell dimensionsa= 7.518(1) Å,b= 13.518(2) Å,c= 14.766(2) Å, V = 1500.7(3) Å3, Z = 4,R1= 0.0301,wR2= 0.0780, S = 1.028. Complex 2 crystallizes as orthorhombic space groupP212121, with unit cell dimensionsa= 7.731(1) Å,b= 13.761(1) Å,c= 14.705(1) Å, V = 1564.4(1) Å3, Z = 4,R1= 0.0230,wR2= 0.0488, S = 1.031. The Zn atom in each of the complexes is four-coordinated in a tetrahedral geometry by the phenolate O and imine N atoms of the Schiff base ligand, and two halide anions. Single crystals of the complexes are stabilized by hydrogen bonds. [ABSTRACT FROM AUTHOR]

A new polymeric zinc(II) complex, [ZnL2(PDA)]n, has been prepared by the reaction of zinc sulfate, 4-nitrophenylacetic acid, and propane-1,3-diamine (PDA) in water. Structure of the complex has been characterized by single-crystal X-ray diffraction. The complex crystallizes as orthorhombic space group Pnma, with unit cell dimensions a = 15.732(1) Å, b = 23.912(1) Å, c = 5.5565(3) Å, V = 2090.2(2) Å3, Z = 4, R1 = 0.0427, wR2 = 0.0968, S = 1.048. The Zn atom is coordinated in a tetrahedral geometry. Single crystals of the complex are stabilized by hydrogen bonds and π..π interactions. [ABSTRACT FROM AUTHOR]

Three Cu(II) complexes, [CuII2(L1)4(L2)2] (1), [CuII2(L1)4(H2O)2]·HL (2), and [CuII2(L1)3(L3)2]ClO4(3), with a ligand derived from protocatechuic acid (HL1 = C9H8O4=2,3-dihydrobenzo[b][1,4]dioxine-6-carboxylic acid, L2 = C7H9N=o-toluidine, L3 = C6H16N2=N,N-diethylethylenediamine) were synthesized and characterized by C, H, and N elemental analysis and single-crystal X-ray diffraction, which revealed that the three complexes have similar binuclear structures. Complexes1and3crystallized in triclinic space groupP-1and2in orthorhombic space groupP212121. The urease inhibitory activities of the three complexes were tested. All three complexes showed strong inhibitory activity againstjack beanurease with an IC50value of 6.8, 5.5, and 3.5 μM compared with the acetohydroxamic acid (IC50 = 7.5 μM), which was a positive control. [ABSTRACT FROM AUTHOR]

Reaction of [MoO2(acac)2] (where acac = acetylacetonate) with two similar hydrazone ligands in ethanol yielded two ethanol-coordinated mononuclear molybdenum(VI) oxo complexes with general formula [MoO2L(EtOH)], where L = L¹ = (N'-(3,5-dibromo-2-hydroxybenzylidene)-4-nitrobenzohydrazide (H2L¹), and L = L² = (N'-(3,5-dibromo-2- hydroxybenzylidene)-2-fluorobenzohydrazide (H2L²). Crystal and molecular structures of the complexes were determined by single crystal X-ray diffraction method. All of the investigated compounds were further characterized by elemental analysis and FT-IR spectra. Single crystal X-ray structural studies indicate that the hydrazone ligands coordinate to the MoO2 cores through enolate oxygen, phenolate oxygen and azomethine nitrogen. The Mo atoms in both complexes are in octahedral coordination. Thermal stability of the complexes has also been studied. [ABSTRACT FROM AUTHOR]

A new mononuclear Schiff base cobalt(III) complex, [Co(MEA) (N3)(DMF)] (1), and a new mononuclear Schiff base manganese(III) complex, [Mn(EEA)(N3)(OH2)] (2) (MEA is bis (5-methoxysalicylidene)ethylenediamine; EEA is bis(6-ethoxys alicylidene)ethylenediamine), have been prepared and structurally characterized by physicochemical and single-cyrstal X-ray diffraction. Complex 1 crystallizes in the monoclinic space groupP21/cwith unit cell dimensionsa= 9.910(1) Å,b= 19.279(1) Å,c= 12.410(1) Å,β= 102.729(2)°, V = 2312.8(2) Å3, Z = 4,R1= 0.0319, andwR2= 0.0779. Complex 2 crystallizes in the monoclinic space groupP21/cwith unit cell dimensionsa= 14.252(2) Å,b= 22.227(3) Å,c= 13.613(2) Å,β= 91.512(2)°, V = 4310.7(11) Å3, Z = 8,R1= 0.0392, andwR2= 0.0839. The metal atom in each complex is in an octahedral coordination. Crystal of complex 2 was stabilized by hydrogen bonds. [ABSTRACT FROM PUBLISHER]

A new azido-bridged polymeric copper(II) complex, [CuL(μ1,3-N3)]n·2nH2O (1), and a new thiocyanato-bridged polymeric copper(II) complex, [CuL(μ1,3-NCS)]n(2) (L = 4-methoxy-2-[(2-morpholin-4-ylethylimino)methyl]phenolate), have been prepared and structurally characterized by elemental analysis, IR spectra, and single-crystal X-ray determination. Each Cu atom in the complexes is coordinated by three donor atoms of Schiff bases and by two atoms of the pseudohalide ligands, forming a square pyramidal geometry. Azide and thiocyanate anions are preferred bridging groups for the construction of polymeric copper complexes with Schiff bases. [ABSTRACT FROM AUTHOR]

A novel bromido- and azido-bridged dinuclear copper(II) complex, [Cu2Br2L2]·[Cu2Br(N3)L2]·H2O, where L is the deprotonated form of the Schiff base 4-chloro-2-[(2-hydroxyethylimino)methyl]phenol, has been prepared and structurally characterized by elemental analysis, IR spectra, and single crystal X-ray crystallography. Each Cu atom in the complex is coordinated by three donor atoms of Schiff base ligand and by two bridging atoms, forming a square pyramidal geometry. The bromide and azide ligands are preferred bridging groups for the construction of dinuclear copper complexes with Schiff bases. [ABSTRACT FROM AUTHOR]

Abstract: Three new coordination polymers, [M1.5(stp)(bpe)(H2O)] (M=Mn(1), Cd(2), Zn(3)) have been prepared by hydro-/solvo-thermal reactions of 2-sulfoterephthalate (stp) and 1,2-bis(4-pyridyl)ethane (bpe) ligands with d-block Mn(II), Cd(II) and Zn(II) salts. Complexes 1 and 2 are isomorphic except for the difference of the metal ions, while complexes 1–3 are polymorphic because of the different coordination modes that stp ligand adopts. The left- and right-handed helixes construct 2D layer from metal ions and stp ligands for 1–3, and the anti-bpe ligands as the pillars complete 3D structure. All the three complexes exhibit a new (2,3,4)-connected network with the Schläfli symbol {8;122}4{82; 12; 142; 16}{8}2 based on the different structural motifs. The magnetic properties of 1 reveal that there exists weak antiferromagnetic coupling between the Mn(II) ions. And the solid-state photoluminescence of 2 and 3 can be attributed to the intraligand π–π* transition. [Copyright &y& Elsevier]

Two spatially confined La0.8Ca0.2MnO3 (LCMO) microbridges with different widths, starting from a single LCMO film (3 mm×5 mm), are fabricated by optical lithography. A second new and robust metal-insulator transition (MIT) peak at about 75 K appears, in addition to the normal MIT at 180 K observed in the standard LCMO film. When the two bridges are processed by currents of high densities, interesting reversible resistance jumps are excited only around the new peak. A stronger dependence of resistance jump on current excitation is found for the bridge with a smaller width. The temperature driven transition between new excited multiple metastable states are involved to explain the interesting low-temperature ultra-sharp jumps. [ABSTRACT FROM AUTHOR]

Five new metal–organic frameworks (MOFs), named [Zn 2 (aobtc)(H 2 O) 4 ] ( 1 ), [Mn 3 (Haobtc) 2 (DMA) 2 (H 2 O) 2 ]·2H 2 O ( 2 ), [Co 3 (Haobtc) 2 (H 2 O) 4 ]·11H 2 O ( 3 ), [Co 3 (aobtc) 2 ]·Himi·H 3 O·3H 2 O ( 4 ), [Cd 2 (aobtc)(bpy)]·4.5H 2 O ( 5 ) (H 4 aobtc = 3,3′,5,5′-azoxybenzenetetracarboxylic acid, bpy = 4,4′-bipyridine, imi = imidazole), have been designed and syntheses. Their structures were determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra and TG analyses. The five compounds exhibit diverse secondary building units (SBUs) and show various structures with different porosity. Compound 1 is a two-dimensional (2D) layer with (4,4)- sql topology based on binuclear Zn cluster (SBU). Both compounds 2 and 3 possess 2D framework with (3,6)-connected kgd topology, based on trinuclear Mn and Co clusters, respectively. Compound 4 shows a 3D framework with (3,8)-connected flu topology, containing linear trinuclear Co clusters as 8-connected nodes. The 3D framework of Compound 5 is built from infinite Cd–O–Cd rod SBUs. The effects of stacking modes on the crystal architectures are discussed. The solid-state photoluminescence for 1 and 5 , the magnetic properties for 2 – 4 , and CO 2 adsorption for 3 were also investigated. [ABSTRACT FROM AUTHOR]

Abstract: The first example of a novel acetylhydroxamate-coordinated oxovanadium(V) complex with hydrazone ligand has been prepared and structurally characterized. The urease inhibitory activity of the complex was assayed, and the molecular docking study was performed. The complex has strong urease inhibitory activity. The introduction of acetylhydroxamate ligand as functional urease inhibitory group may increase the activity of the complex. [Copyright &y& Elsevier]

Abstract: A series of 2,5-substituted-1,4-benzoquinone (1–6) were prepared and structurally characterized by elemental analysis, IR spectra, 1H and 13C NMR spectra, and single crystal X-ray determination. The urease inhibitory activities of the compounds against H. pylori urease were studied. Among the compounds, 2,5-bis(2-morpholin-4-ylethylamino)-[1,4]benzoquinone (2) shows the most effective activity with IC50 value of 27.30±2.17μM. Docking simulation was performed to insert compound 2 into the crystal structure of H. pylori urease at the active site to determine the probable binding mode. As a result, compound 2 may be used as a potential urease inhibitor. [Copyright &y& Elsevier]