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Designing and developing small organic molecules for use as urease inhibitors is challenging due to the need for ecosystem sustainability and the requirement to prevent health risks related to the human stomach and urinary tract. Moreover, imaging analysis is widely utilized for tracking infections in intracellular and in vivo systems, which requires drug molecules with emissive potential, specifically in the low-energy region. This study comprises the synthesis of a Schiff base ligand and its selected transition metals to evaluate their UV/fluorescence properties, inhibitory activity against urease, and molecular docking. Screening of the symmetrical cage-like ligand and its metal complexes with various eco-friendly transition metals revealed significant urease inhibition potential. The IC50 value of the ligand for urease inhibition was 21.80 ± 1.88 µM, comparable to that of thiourea. Notably, upon coordination with transition metals, the ligand–nickel and ligand–copper complexes exhibited even greater potency than the reference compound, with IC50 values of 11.8 ± 1.14 and 9.31 ± 1.31 µM, respectively. The ligand–cobalt complex exhibited an enzyme inhibitory potential comparable with thiourea, while the zinc and iron complexes demonstrated the least activity, which might be due to weaker interactions with the investigated protein. Meanwhile, all the metal complexes demonstrated a pronounced optical response, which could be utilized for fluorescence-guided targeted drug delivery applications in the future. Molecular docking analysis and IC50 values from in vitro urease inhibition screening showed a trend of increasing activity from compounds 7d to 7c to 7b. Enzyme kinetics studies using the Lineweaver–Burk plot indicated mixed-type inhibition against 7c and non-competitive inhibition against 7d. [ABSTRACT FROM AUTHOR]

Three new trinuclear complexes containing either nickel(II), copper(II) or zinc(II), [Ni3L2(NO3)2(CH3OH)2]·2CH3OH (1), [Cu3Br2L2] (2), [Zn3L2(NCS)2(CH3OH)2]·0.5CH3OH·0.5H2O (3), and a new dioxidomolybdenum(VI) complex, [MoO2L] (4), have been prepared from the bis-Schiff base N,N'-bis(4-bromosalicylidene)-1,3-propanediamine (H2L) with various metal salts in methanol. The complexes were characterized by elemental analysis, IR and UV–Vis spectra. Molecular structures were confirmed by single crystal X-ray diffraction experiments. The Ni ions in 1 adopt an octahedral coordination environment, bridged by phenolate oxygen and nitrate ligands. The Cu ions in 2 are square pyramidal and square planar, and the Zn ions in 3 are square pyramidal and octahedral. The metal atoms in 2 and 3 are bridged by phenolate oxygen donors. The Mo ion in 4 is octahedral. The Schiff base ligand coordinates to the metal atoms through two phenolate O and two imino N donors. Biological assays revealed that the nickel and copper complexes have effective urease inhibition. [ABSTRACT FROM AUTHOR]

A new tetranuclear copper(II) complex [Cu4L2(N3)2(CH3OH)2](NO3)2·4CH3OH (1) and a new trinuclear zinc(II) complex [Zn3L2(CH3COO)2] (2) have been prepared from the bis-Schiff base N,N'-bis(4-bromosalicylidene)-1,3-propanediamine (H2L) with copper nitrate and zinc acetate, respectively, in the presence of sodium azide. The complexes were characterized by elemental analysis, IR and UV-Vis spectroscopy. Molecular structures of both complexes were confirmed by single crystal X-ray determination. The Cu(II) atoms in complex 1 are bridged by phenolate oxygen atoms and end-on azide ligands. The Zn(II) atoms in complex 2 are bridged by phenolate oxygen atoms and acetate ligands. The Cu(II) atoms in complex 1 are in square planar and square pyramidal coordination. The Zn(II) atoms in complex 2 are in square pyramidal and octahedral coordination. The Schiff base ligand coordinates to the metal atoms through two phenolate O and two imino N atoms. The biological assay reveals that the copper(II) complex has effective urease inhibition. [ABSTRACT FROM AUTHOR]

Five copper(II), zinc(II) and nickel(II) complexes, [Cu2L2(μ1,1-N3)2] (1), [Zn2L2(μ2-η1:η1-CH3COO)(NCS)]EtOH (2), [Zn2L2(μ2-η1:η1-CH3COO)(N3)]MeOH (3), [Zn2Cl2L2] (4) and [NiL(HL)]ClO4 (5), were prepared from the Schiff base 3-methyl-2-((pyridin-2-ylmethylene)amino)phenol (HL). The compounds have been characterized by physico-chemical methods including elemental analysis, IR, and UV–Vis spectra. Structures of the five new complexes were determined by single crystal X-ray diffraction. The copper ions in 1 are in square pyramidal, while zinc ions in 2, 3, and 4 are distorted square pyramidal, and the nickel ions in 5 are octahedral. The biological assay indicated that zinc complex 2 has the most effective activity on Jack bean urease with IC50 = 1.7 ± 0.8 μmol·L−1. Molecular docking was performed to study the interaction between the active center of the urease with molecules of the complexes. [ABSTRACT FROM AUTHOR]

Three copper(II) and cobalt(III) complexes, [CuL(dca)]n (1), [CuL(N3)]n (2) and [CoL(N3)2(DMF)] (3), where L is the monoanionic form of the Schiff base (((2-(pyrrolidin-1-yl)ethyl)imino)methyl)naphthalen-2-ol (HL), and dca is dicyanamide, have been prepared and characterized by elemental analyses, IR and UV-Vis spectroscopy, as well as single crystal X-ray diffraction. The Cu atoms in complexes 1 and 2 are in square pyramidal coordination, and the Co atom in complex 3 is in octahedral one. Complexes 1 and 2 inhibit the Jack bean urease with IC50 values of 0.25 ± 0.14 and 0.32 ± 0.15 μmol L-1, respectively. Complex 3 show weak activity on Jack bean urease with percentage inhibition of 37%. [ABSTRACT FROM AUTHOR]

Three mononuclear copper(II) and nickel(II) complexes, [Cu(L1)(NCS)(CH3OH)] (1), [Cu(L2)(NCS)] (2) and [Ni(L2)(N3)] (3), where L1 and L2 are the monoanionic forms of the Schiff bases N'-(pyridin-2-ylmethylene)picolinohydrazide (HL1) and 4-methyl-2-(((pyridin-2-ylmethyl)imino)methyl)phenol (HL2), have been prepared and characterized by elemental analysis, IR and UV-Vis spectroscopy, as well as single crystal X-ray diffraction studies. The Cu atom in complex 1 is in a square pyramidal coordination, with the three N atoms of the ligand L and the N atom of the thiocyanate ligand in the basal plane, and with the methanol O atom at the apical position. The Cu and Ni atoms in complexes 2 and 3 are in square planar coordination, with the three donor atoms of the Schiff base ligands and the terminal N atoms of thiocyanate and azide ligands. Complexes 1 and 2 inhibit the Jack bean urease with IC50 value of 0.33±0.12 and 0.39±0.10 μmol L–1, respectively. Molecular docking study was performed to investigate the interaction between the complexes and the enzyme.

A pair of structurally similar dicyanamide bridged copper(II) and zinc(II) complexes [CuL(dca)]n (1) and [ZnL(dca)]n (2), were prepared from the fluorine containing Schiff base 5-fluoro-2-(((2-hydroxyethyl)imino)methyl)phenol (HL). The compounds were characterized by physico-chemical methods. Structures of the complexes were confirmed by single crystal X-ray diffraction. The Cu atom in complex 1 is in square pyramidal coordination, whereas the Zn atom in complex 2 is in trigonal bipyramidal coordination. The copper complex has effective Jack bean urease inhibitory activity, with IC50 value of 0.14±0.12 μmol L–1. 搜索 复制

Three new zinc(II) complexes, [Zn3(µ2-η¹:η¹-OAc)2(µ2-η2:η0-OAc)2L2] (1), [Zn3(µ2-η¹:η¹-OAc)2(µ1,1-N3)(N3)L2] (2), [Zn2(µ1,3-N3)(N3)(H2O)L2] (3), with the Schiff base ligand 4-chloro-2-(((2-(pyrrolidin-1-yl)ethyl)imino)methyl)phenol (HL) have been synthesized and characterized by elemental analysis, IR and UV-Vis spectroscopic studies. Crystal structures of the complexes were confirmed by single crystal X-ray diffraction. Complex 1 is a bidentate acetato, monoatomic bridging acetato, and phenolato co-bridged trinuclear zinc compound. The Zn atoms are in octahedral and square pyramidal coordination. Complex 2 is a bidentate acetato, end-on azido, and phenolato co-bridged trinuclear zinc compound. The Zn atoms are in trigonal bipyramidal and square pyramidal coordination. Complex 3 is an end-to-end azido bridged dinuclear zinc compound. The Zn atoms are in square pyramidal and trigonal bipyramidal coordination. The Schiff base ligands in the complexes coordinate to the Zn atoms through the phenolate oxygen, imino nitrogen and pyrrolidine nitrogen. The complexes have interesting inhibitory activity on Jack bean urease, with IC50 values of 7.1-15.3 µmol·L-1. [ABSTRACT FROM AUTHOR]

A centipede like thiocyanate-bridged multi-nuclear copper(I/II) complex, [Cu2L(CH3OH)(NCS)3]n, derived from 2-(((2-(dimethylamino)ethyl)imino)methyl)-5-fluorophenol (HL), was prepared and characterized by elemental analysis, IR and UV–vis spectra, as well as single crystal X-ray diffraction. The Cu1 ion in the +2 oxidation state is coordinated by the tridentate Schiff base ligand in a square pyramidal geometry, with the other two sites occupied by one N atom of the thiocyanate ligand and one methanol O atom. The Cu2 ion in the +1 oxidation state is coordinated by one N and three S atoms from four thiocyanate ligands, forming a tetrahedral geometry. The CuI ions are linked by thiocyanate ligands to form a one-dimensional chain with [CuI2(μ1,3,3-NCS)2] as the repeat unit. The [CuIIL(CH3OH)] moieties are linked to the chain through thiocyanate ligands. The complex has remarkable inhibitory activity on Jack bean urease with an IC50 value of 1.3 μmol L–1. [ABSTRACT FROM AUTHOR]

A series of copper, nickel and zinc complexes, [CuClL] (1), [CuBrL] (2), [NiL2] (3), [ZnL2] (4) and [Zn2I2L2] (5), where L is the deprotonated form of 4-chloro-2-((pyridin-2-ylmethylene)amino)phenol, have been synthesized and characterized by elemental analysis, IR and UV-Vis spectra. The structures of the complexes were further confirmed by single crystal X-ray diffraction. The Cu ions in 1 and 2 are in square planar coordination. The Ni and Zn ions in 3 and 4 are in octahedral coordination. The coordination of the Zn ions in centrosymmetric complex 5 is between square pyramidal and trigonal bipyramidal. The copper complexes have excellent urease inhibitory activity. [ABSTRACT FROM AUTHOR]

An end-on azido-bridged dinuclear copper(II) complex, [Cu2L2(μ1,1-N3)2], where L is the deprotonated form of N-(2-hydroxy-4-methoxybenzylidene)picolinamide (HL), has been prepared by the reaction of 5-methoxy-2-[(pyridin-2-ylmethylimino)methyl]phenol (HL′) with copper bromide and sodium azide in methanol. The structure of the complex was characterized by elemental analysis, IR and UV–vis spectra, and single crystal X-ray diffraction. The complex possesses crystallographic inversion symmetry, with the two Cu ions (3.36 Å) bridged by two end-on azido bridges. Each Cu ion is in a square pyramidal coordination. The original ligand HL′ was unexpectedly oxidized to HL under mild conditions during preparation of the complex. The complex has excellent urease inhibitory activity. [ABSTRACT FROM AUTHOR]

Two copper(II) complexes, [Cu2(L1)2]·2H2O (1) and [Cu3(L1)2(NCS)2] (2), and two nickel(II) complexes, [NiL2(NCS)] (3) and [Ni(L2)2(NCS)]·CH3OH (4), were prepared from the fluorine substituted Schiff bases N,N'-bis(4-fluorosalicylidene)-1,2-diaminopropane (H2L1) and 4-fluoro-2-[(2-isopropylaminoethylimino)methyl]phenol (HL2), respectively. The compounds were characterized by physico-chemical methods. Structures of the complexes were further confirmed by single crystal X-ray diffraction. The Cu ions in 1 are square pyramidal, and in 2 are square planar and octahedral. The Ni ion in 3 is square planar, and in 4 is octahedral. All the complexes have effective Jack bean urease inhibitory activities. Complex 1 has the most effective activity, with an IC50 value of 2.1 ± 1.3 μmol L−1. [ABSTRACT FROM AUTHOR]

A quinoline functionalized two novel fluorescent Schiff bases, N-(quinolin-2-ylmethylene) anthracen-1-amine (SB1) and 2-(quinolin-2-ylmethyleneamino) benzene thiol (SB2) were synthesized and confirmed by using 1H NMR, IR and GC-MS techniques. The spectroscopic properties were examined by absorption spectroscopy and fluorescence spectroscopy. The absorption and fluorescence spectra of the probes (SB1 and SB2) were measured in a variety of solvents. Both the compounds were tested for urease inhibitory activity. The synthesized compound SB2 proved to be the most effective screening for enzyme inhibitory activity with IC50 = 0.111 μM than SB1 (IC50 = 0.287 μM). Molecular docking studies were performed to delineate the binding affinity and conformational positions of chemical compounds within the active region of the target protein. In-vitro analysis depicts the potency of SB1 in free radical scavenging as compared to the reference drug vitamin C. [ABSTRACT FROM AUTHOR]

[Display omitted] • Six new copper(II) and nickel(II) complexes were prepared. • The complexes have been characterized by single crystal X-ray diffraction. • The complexes are versatile polynuclear compounds. • The copper complexes have effective urease inhibitory activity. Four new copper(II) and two new nickel(II) complexes, [Cu 2 (μ-Br) 2 L 2 ] (1), [CuL(μ 1,3 -NCS)] n (2), [Cu 2 L 2 (μ 1,3 -N 3) 2 ] (3), [Cu 3 Cl 2 (μ-Cl) 2 L 2 ] (4), [Ni 3 L 2 (μ 2 -η1:η1-OAc) 2 (μ 2 -η2:η1-OAc) 2 ]·2CH 3 OH (5) and [NiL(μ 2 -1,5-dca)(OH 2)] n (6), where L is the deprotonated form of 5-bromo-2-(((2-pyrrolidin-1-yl)ethyl)imino)methyl)phenol, dca is dicyanoamide, were synthesized and characterized by elemental analyses, infrared and electronic spectroscopy, and single crystal X-ray determination. The Cu atoms in complexes 1 – 3 and the outer two Cu atoms in complex 4 are in square pyramidal coordination, while the central Cu atom in complex 4 is in square planar geometry. The Ni atoms in complexes 5 and 6 are in octahedral coordination. The co-ligands bromide, thiocyanate, azide, chloride, acetate and dicyanoamide are interesting bridging groups in the construction of the polynuclear complexes with versatile structures. The urease inhibition assay indicates that the copper complexes have effective activities. [ABSTRACT FROM AUTHOR]

Four new nickel(II), cadmium(II), copper(II) and iron(III) complexes were prepared. The structures of the complexes were characterized by single crystal X-ray diffraction. The Jack bean urease inhibitory assay indicated that the copper complex has remarkable activity. [Display omitted] Four new nickel(II), cadmium(II), copper(II) and iron(III) complexes, [Ni 3 (L1) 2 (μ 2 - η 1: η 1-CH 3 COO) 2 ] (1), [Cd 2 (L1) 2 (CH 3 OH) 2 ] (2), [Cu(L2)] (3) and [Fe 2 (L3) 2 (μ 2 -OCH 3) 2 ] (4), where L1, L2 and L3 are the dianionic form of N,N' -bis(5-fluorosalicylidene)-1,3-propanediamine (H 2 L1), N,N' -bis(3,5-difluorosalicylidene)-1,3-propanediamine (H 2 L2) and N,N' -bis(4-fluorosalicylidene)-1,3-propanediamine (H 2 L3), respectively, were prepared. The compounds have been characterized by physico-chemical methods. The structures of the metal complexes were also confirmed by single crystal X-ray diffraction. The Ni atoms in complex 1 are in square pyramidal and octahedral coordination environments. The Cd atoms in complex 2 are in an octahedral coordination environment. The Cu atom in complex 3 is in a tetrahedrally distorted square planar coordination environment. The Fe atoms in complex 4 are in an octahedral coordination environment. The Jack bean urease inhibitory assay indicated that the copper complex displays good activity. [ABSTRACT FROM AUTHOR]

A series of new cobalt(III) complexes were prepared. They are [CoL 1 (py) 3 ]·NO 3 ( 1 ), [CoL 2 (bipy)(N 3 )]·CH 3 OH ( 2 ), [CoL 3 (HL 3 )(N 3 )]·NO 3 ( 3 ), and [CoL 4 (MeOH)(N 3 )] ( 4 ), where L 1 , L 2 , L 3 and L 4 are the deprotonated form of N ′-(2-hydroxy-5-methoxybenzylidene)-3-methylbenzohydrazide, N ′-(2-hydroxybenzylidene)-3-hydroxylbenzohydrazide, 2-[(2-dimethylaminoethylimino)methyl]-4-methylphenol, and N , N ′-bis(5-methylsalicylidene)- o -phenylenediamine, respectively, py is pyridine, and bipy is 2,2′-bipyridine. The complexes were characterized by infrared and UV–Vis spectra, and single crystal X-ray diffraction. The Co atoms in the complexes are in octahedral coordination. Complexes 1 and 4 show effective urease inhibitory activities, with IC 50 values of 4.27 and 0.35 μmol L −1 , respectively. Complex 2 has medium activity against urease, with IC 50 value of 68.7 μmol L −1 . While complex 3 has no activity against urease. Molecular docking study of the complexes with Helicobacter pylori urease was performed. [ABSTRACT FROM AUTHOR]

Three new mononuclear copper(II) complexes, [CuL 1 (N 3 )] ( 1 ), [CuL 1 (NCS)] ( 2 ), and [CuL 2 (NCS)] ( 3 ), where L 1 is the monoanionic form of 5-diethylamino-2-[(pyridin-2-ylmethylimino)methyl]phenol (HL 1 ), and L 2 is the monoanionic form of 2-[1-(2-piperidin-1-ylethylimino)ethyl]phenol (HL 2 ), have been synthesized and characterized by physico-chemical methods, as well as single crystal X-ray determination. The Cu atoms in the complexes are coordinated by the donor atoms of the Schiff base ligands and nitrogen atom of the pseudohalide ligands, forming square planar geometry. The complexes showed effective urease inhibitory activities. Complex 1 showed the most urease inhibitory activity, with IC 50 value of 1.5 ± 1.1 μM. Molecular docking study of the complexes with Helicobacter pylori urease was performed. As a result, complex 1 matches well with the cavity of the active center of the urease, and forms weak interaction with residues ASP 316, LEU 318, MET 317, CYS 321, HIS 322 and ARG 328. [ABSTRACT FROM AUTHOR]

Three mononuclear copper(II), manganese(III), and iron(III) complexes, [CuL(OH2)] (1), [MnClL] (2), and [FeClL] (3), where L is the deprotonated form of N,N’-bis(4-methoxysalicylidene) ethylenediamine, were synthesized and structurally characterized by physicochemical methods and single-crystal X-ray diffraction. Each metal atom in the complexes adopts a square pyramidal coordination, with the four donor atoms of the Schiff base defining the basal plane, and with the water molecule for 1, and chloride atom for 2 and 3 occupying the apical position. The complexes were evaluated in vitro for their inhibitory activities against Jack bean urease. The copper complex showed effective inhibitory activity against the urease. A docking simulation was performed for the copper complex into the active site of the urease to investigate the probable binding conformation. [ABSTRACT FROM PUBLISHER]

Two mononuclear nickel(II) complexes, [Ni(MMP)(NCS)] (1) and [Ni(PMP)(NCS)] (2), where MMP = 5-methoxy-2-[(2-morpholin-4-ylethylimino)methyl]phenolate, PMP = 5-methoxy-2-[(pyridin-2-ylmethylimino)methyl]phenolate, were prepared and structurally characterized by X-ray diffraction. The Ni atom in each complex is four-coordinated by three donor atoms of the Schiff base ligand, and by one thiocyanate N atom, forming a square planar coordination. The urease inhibitory activity of the complexes was evaluated. [ABSTRACT FROM PUBLISHER]

Abstract: A series of oxovanadium(V) complexes, [VO2L1]2 (1), [VO2L2]2 (2), [VO2L3]2 (3), [VO2L4]2 (4), [VO(OCH3)L5] (5), and [VO(OCH3)(HOCH3)L6] (6) (HL1 =2-ethoxy-6-{[2-(2-hydroxyethylamino)ethylimino]methyl}phenol, HL2 =4-chloro-2-{[2-(2-hydroxyethylamino)ethylimino]methyl}phenol, HL3 =2-methoxy-6-[(2-methylaminoethylimino)methyl]phenol, HL4 =4-chloro-2-[(2-methylaminoethylimino)methyl]phenol, HL5 = N′-(2-hydroxy-3-ethoxybenzylidene)-3-hydroxy-2-naphthohydrazide, and HL6 = N′-(2-hydroxy-5-chlorobenzylidene)-3-hydroxy-2-naphthohydrazide), have been prepared and structurally characterized by physico-chemical methods and X-ray diffraction. The inhibition rates (%) with the concentration of 100μM for the complexes on Helicobacter pylori urease are 18.96±0.44 (1), 33.01±1.80 (2), 35.83±0.78 (3), 48.09±1.23 (4), 45.91±2.09 (5), and 90.72±1.91 (6). The relationship between the structures and urease inhibitory activities indicates that the chloro-substituted complexes have stronger activity than the alkoxy-substituted complexes. It is notable that one of the chloro-substituted complexes has very strong urease inhibitory activity, with IC50 value of 17.35±1.01μM, which is much lower than that of the acetohydroxamic acid coassayed as a standard urease inhibitor. The kinetic studies reveal that the complex is a mixed-competitive inhibitor of urease. The molecular docking study of the complexes with the Helicobacter pylori urease was performed. [Copyright &y& Elsevier]

Two new similar zinc(II) complexes, [ZnI2L] (1) and [Zn(NCS)2L] (2), derived from the Schiff base (2-piperidin-1-ylethyl)-(1-pyridin-2-ylethylidene)amine(L), were prepared and structurally characterized by X-ray diffraction. The Zn atom in each complex is five-coordinated by the three N atoms of the Schiff base ligand, and by two I or N atoms of the terminal iodide or thiocyanate groups, forming distorted square-pyramidal coordination. The urease inhibitory activities of the complexes and the ligand were evaluated. [ABSTRACT FROM PUBLISHER]

Four new nickel(II), zinc(II), and cobalt(II) complexes, [Zn(L1)2] · H2O (1), [Ni(L1)2] · H2O (2), [Ni(L2)2] (3), and [Co(L3)2] · H2O (4), derived from hydroxy-rich Schiff bases 2-{[1-(5-chloro-2-hydroxyphenyl)methylidene]amino}-2-methylpropane-1,3-diol (HL1), 2-{[1-(2-hydroxy-3-methoxyphenyl)methylidene]amino}-2-ethylpropane-1,3-diol (HL2), and 2-{[1-(5-bromo-2-hydroxyphenyl)methylidene]amino}-2-methylpropane-1,3-diol (HL3) have been synthesized and characterized by elemental analyses, infrared spectroscopy, and single-crystal X-ray determination. Each metal in the complexes is six-coordinate in a distorted octahedral coordination. The Schiff bases coordinate to the metal atoms through the imino N, phenolate O, and one hydroxyl O. In the crystal structures of HL1 and the complexes, molecules are linked through intermolecular O–H···O hydrogen bonds, forming 1-D chains. The urease inhibitory activities of the compounds were evaluated and molecular docking study of the compounds with the Helicobacter pylori urease was performed. [ABSTRACT FROM PUBLISHER]

Abstract: A series of new and novel Schiff base derivatives were synthesized and investigated as potential new inhibitors of Jack bean urease. The most potent compounds were 3f with (K i = 0.09 μM) and 3k (K i = 0.122 μM). A pure competitive mechanism of inhibition was observed. Molecular docking studies were also performed to illustrate the binding mode of the compounds. Docking studies were performed on both enzymes from Jack bean urease and H. pylori urease. It was observed that both share the same binding mode. The binding sites of the two urease structures also aligned very well indicating the similarity in binding sites of the enzymes. [Copyright &y& Elsevier]

A series of structurally similar dinuclear oxovanadium(V) complexes, [VO2L]2 (L = L1 = 2-[(2-methylaminoethylimino)methyl]phenolate (1); L = L2 = 2-[(2-ethylaminoethylimino)methyl]phenolate (2); L = L3 = 2-[(2-isopropylaminoethylimino)methyl]phenolate (3)), has been synthesized and characterized by physico-chemical methods and single-crystal X-ray diffraction. The V in each complex is octahedral, with three donors of L and one oxo defining the equatorial plane, and with two oxos occupying the axial positions. The complexes were tested for their urease inhibitory activities. The inhibition rate (%) of 1, 2, and 3 at 100 µmol L−1 on urease are 67 ± 1, 53.5 ± 0.9, and 44 ± 1. The relationship between structures of the complexes and the urease inhibitory activities indicates that shorter terminal groups of the complexes have stronger activities against urease. Molecular docking study of the complexes with the Helicobacter pylori urease was performed. [ABSTRACT FROM PUBLISHER]

Abstract: Two new thiocyanato-coordinated manganese(III) complexes with bis-Schiff bases have been unprecedented prepared from N-ethylethane-1,2-diamine and N-(2-hydroxyethyl)ethane-1,2-diamine as the starting materials with equimolar quantities of 4-methoxysalicylaldehyde and 3-ethoxysalicylaldehyde, respectively. It was found that the reaction can process only in the presence of manganese salts and ammonium thiocyanate. The urease inhibitory activity of the complexes was tested. [Copyright &y& Elsevier]

Abstract: A series of hetero-dinuclear CuII–ZnII complexes, [CuZnCl2L1] (1), [CuZnCl2L2] (2), [CuZnBr2L3] (3), [CuZnBr2L4(DMF)] (4), [CuZnCl2L4] (5), [CuZnCl2L5] (6), [CuZnCl2L3] (7) and [CuZnBr2L1] (8), where L1, L2, L3, L4 and L5 are the deprotonated forms of N,N′-bis(3-ethoxysalicylidene)-1,3-propanediamine (H2L1), N,N′-bis(2-hydroxynaphthylmethylidene)-1,3-propanediamine (H2L2), N,N′-bis(3-methoxysalicylidene)-1,3-propanediamine (H2L3), N,N′-bis(salicylidene)-1,3-propanediamine (H2L4) and N,N′-bis(salicylidene)-1,4-butanediamine (H2L5), respectively, have been synthesized and characterized by physico-chemical methods and single-crystal X-ray diffraction. The complexes were tested for their urease inhibitory activity. Complexes 1 and 8 show effective urease inhibitory activity with IC50 values of 2.2 and 10.7μM. The molecular docking study of the complexes with the Helicobacter pylori urease was performed. [Copyright &y& Elsevier]

Abstract: A series of structurally similar oxovanadium(V) complexes with analogous Schiff bases have been prepared and structurally characterized. The urease inhibitory activities of the complexes were investigated. The shorter the terminal groups of the Schiff base ligands are, the stronger the urease inhibitory activities of the oxovanadium(V) complexes. [Copyright &y& Elsevier]

Two new Schiff base zinc(II) complexes, [ZnL1IN3] (1) and [ZnL2(N3)2] (2) (L1 = 2-[(3-cyclohexylaminopropylimino)methyl]-6-ethoxyphenol, L2 = 2-[(3-cyclohexylaminopropylimino)methyl]-6-methoxyphenol), were prepared and structural characterized by elemental analyses, infrared spectroscopy, and single-crystal X-ray diffraction. Both complexes are mononuclear zinc(II) compounds. The Zn atom in each complex is four-coordinated in a tetrahedral geometry. Both complexes show urease inhibitory activities. [ABSTRACT FROM AUTHOR]

Abstract: In order to explore novel urease inhibitors, three new mononuclear complexes of Cu(II) and Zn(II) with Schiff base 2-{[2-(2-hydroxyethylamino)ethylimino]methyl}-4-nitrophenol have been prepared and structurally characterized by X-ray crystallography. Among the three complexes, two Cu(II) complexes show strong urease inhibitory activities with the IC50 values being much lower than that of the acetohydroxamic acid, while the Zn(II) complex shows no activity at the concentration of 100 μM. [Copyright &y& Elsevier]

Abstract: A bis-Schiff base trinuclear cobalt(II) complex was synthesized under solvolthermal conditions from a mono-Schiff base ligand and cobalt acetate. The complex was characterized by elemental analysis, IR spectrum and X-ray single crystal determination. The urease inhibitory activity was evaluated. [Copyright &y& Elsevier]