Vanadium is a hard, silver-grey transition metal found in at least 60 minerals and fossil fuel deposits. Its oxide and other vanadium salts are toxic to humans, but the toxic effects depend on the vanadium form, dose, exposure duration, and route of intoxication. Vanadium is used by some life forms as an active center in enzymes, such as the vanadium bromoperoxidase of ocean algae and nitrogenases of bacteria. The structure and biochemistry of vanadate resemble those of phosphate, hence vanadate can be regarded as a phosphate competitor in a variety of biochemical enzymes such as kinases and phosphatases. In this review, we describe the biochemical pathways regulated by vanadium compounds and their potential therapeutic benefits for a range of disorders including type 2 diabetes, cancer, cardiovascular disease, and microbial pathology.

Two new copper (II) complexes with the third generation quinolone antibacterial agent levofloxacin, 2-aminopyridine and 2,2 '-bipyridine nitrogen-based ligands with the following molecular structures [Cu (levo)(2)(2-ampy)].6.25H(2)O (1) and [Cu (levo)(H2O)(2,2-bipy)](NO3).2.5H(2)O (2) were synthesized. The complexes were characterized by spectroscopic methods and others. The crystal structure of complex 1 revealed that the Cu (II) cation is coordinated to two bidentate chelating levofloxacinato ligands, and one monodentate 2-ampy ligand in the axial position forming a slightly distorted square pyramidal geometry. The mononuclear cationic complex 2 was determined in the triclinic crystal system and the chiral space group P1 with four molecules per unit cell in which the Cu (II) cation is coordinated to one bidentate chelating levofloxacinato ligand, one bidentate 2,2-bipy, and one water molecule in a distorted square pyramidal geometry. In vitro antibacterial activities for the complexes and their parent ligands against four gram-negative bacteria (Proteus mirabilis, Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumonia) and four gram-positive bacteria (Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, and Enterococcus faecalis) using the agar diffusion method have been determined with inhibition zone diameter (IZD) values between 29 and 46 mm. In addition, the minimum inhibition concentration (MIC) and the minimum bactericidal concentration (MBC) have been investigated. The MIC results of complexes 1 and 2 showed significant antibacterial activities against the P. mirabilis and B. subtilis than levofloxacin.

Starting from the proposed zinc carboxylate cluster tetrakis(μ-2-propylpentanoato)dizinc(II), Zn2(μ2-valp)4 (I), of valproic acid, a branched short-chain fatty acid, and bipyridine ligands, two new mixed-ligand coordination compounds, namely, bis(2,2'-bipyridine)di-μ3-hydroxido-hexakis(μ-2-propylpentanoato)bis(2-propylpentanoato)pentazinc(II), [Zn5(C8H15O2)8(OH)2(C10H8N2)2] (II), and poly[[bis(μ-4,4'-bipyridine)di-μ3-hydroxido-octakis(μ-2-propylpentanoato)bis(2-propylpentanoato)hexazinc(II)] dimethylformamide disolvate], {[Zn6(C8H15O2)10(OH)2(C10H8N2)2]·2C3H7NO}n (III), were synthesized. Compound II is a core-shell-type zero-dimensional discrete Zn5(μ3-OH)2 metal-organic cluster with Zn ions in double-triangle arrangements that share one Zn ion coincident with an inversion centre. The cluster contains three crystallographically non-equivalent Zn ions exhibiting three different coordination geometries (tetrahedral, square pyramidal and octahedral). The cluster cores are well separated and embedded in a protective shell of the aliphatic branched short chains of valproate. As a result, there is no specific interaction between the discrete clusters. Conversely, compound III, a 2D layered coordination network with a secondary building unit (SBU), is formed by Zn6(μ3-OH)2 clusters exhibiting a chair-like hexagonal arrangement. This SBU is formed from two Zn3(μ3-OH) trimers related by inversion symmetry and connected by two syn-anti bridging carboxylate groups. Each SBU is connected by four 4,4'-bipyridine ligands producing a 63-hcb net topology. 2D coordination layers are sandwiched within layers of dimethylformamide molecules that do not interact strongly with the network due to the hydrophobic protection provided by the valproate ligands.

Nepeta curviflora Boiss. (Syrian catnip) is native to the Middle East. This medicinal plant is commonly used against nervous disorders, rheumatic pains, and high blood pressure. Herbal infusions prepared from various Nepeta spp. are extensively consumed as functional food. However, limited information has been known about the phenolic constituents of Syrian catnip. In this study, two acylated flavone 7-O-glucuronides, apigenin 7-O-(2″-O-(2‴-(E-caffeoyl)-β-glucuronopyranosyl)-β-glucuronopyranoside) (1) and luteolin 7-O-(2″-O-(2‴-(E-caffeoyl)-β-glucuronopyranosyl)-β-glucuronopyranoside) (2), along with the known phenolic compounds rosmarinic acid, caffeic acid, apigenin, and apigenin 7-O-β-glucopyranoside were isolated from the aerial parts of N. curviflora. The characterizations of these compounds were based on high-resolution mass spectrometry, UV, and extensive use of multidimensional NMR spectroscopy. The new compounds (1 and 2) were identified in the unmodified state and as dimethylesters.

Novel Zn(II) complexes with the general formula: [Zn(furo) 2 (L) n ], n = 1 or 2, (furo = furosemide = (4‐chloro‐2‐(furan‐2‐ylmethylamino)‐5‐sulfamoylbenzoic acid) were prepared. The complexes [Zn(furo) 2 (MeOH) 2 ] ( 1 ; MeOH = methanol), [Zn(furo) 2 (2‐ampy) 2 ] ( 2 ; 2‐ampy = 2‐aminopyridine), [Zn(furo) 2 (2‐ammepy) 2 ] ( 3 ; 2‐ammepy = 2‐aminomethylpyridine), [Zn(furo) 2 (H 2 O)(2,2‐bipy)] ( 4 ; 2,2′‐bipy = 2,2′‐bipyridine), [Zn(furo) 2 (H 2 O)(4,4′‐bipy)] ( 5 ; 4,4′‐bipy = 4,4′‐bipyridine), [Zn(furo) 2 (1,10‐phen)] ( 6 ; 1,10‐phen = 1,10‐phenanthroline), [Zn(furo) 2 (2,9‐dmp)] ( 7 ; 2,9‐dmp = 2,9‐dimethyl‐1,10‐phenanthroline), and [Zn (furo) 2 (quin) 2 ] ( 8 ; quin = quinoline) were synthesized and characterized using different techniques such as IR, UV–Vis, 1 H NMR, 13 C NMR, LC/MS and others. The crystal structure of complex ( 4 ) was determined using single‐crystal X‐ray diffraction. The anti‐bacterial activity of complexes ( 1 – 8 ) was tested using agar diffusion method against three gram‐positive ( Staphylococcus aureus , Bacillus subtilis and Staphylococcus epidermidis ) and three gram‐negative bacteria ( Escherichia coli , Proteus mirabilis, Pseudomonas aeruginosa ). The obtained results showed different Inhibition Zone Diameters (IZD) with various anti‐bacterial activities against the selected gram‐positive and gram‐negative bacteria. In addition, the rate of bis‐(4‐nitrophenyl) phosphate hydrolysis was measured at different temperatures, different pH values and different concentrations. The rates for the eight complexes were in the following order: complex 4 > 2 > 5 > 8 > 7 > 6 > 3 > 1 .

The synthesis of mononuclear cobalt(II/III) complexes with two different ligands (complex 2: [Co(valp)2(2,9‐dmp)] and complex 3: [Co(valp)2(H2O)(1,10‐phen)]) was investigated and the characterization of both complexes was achieved using IR, UV–Vis, and single crystal X‐ray diffraction. Using single crystal X‐ray diffraction, the crystal structure of each of the complexes was determined. Additionally, the biological activity of these complexes was studied in five gram‐positive and four gram‐negative bacterial strains. Whereas in all gram‐negative bacteria tested, cobalt valproate complexes did not show any anti‐bacterial activity, both complexes had effects on gram positive bacteria. Complex 2 demonstrated good anti‐bacterial activity against all gram‐positive bacteria with inhibition zone diameter (IZD) ranging between 15–28 mm. Complex 3 exhibited low inhibition activity against all gram‐positive bacteria except E. faecalis with IZD ranging between 11.3–13.7 mm. Moreover, as an indication of its uses as industrial catalyst, the rate of bis(p‐nitrophenyl) phosphate (BNPP) hydrolysis when catalyzed by these complexes was measured at different temperatures, concentrations and pH. Complex 2 proved to be a better catalyst to induce the hydrolysis of BNPP.

New cobalt valproate complexes with different nitrogen based ligands were synthesized and characterized using various techniques such as IR, UV–Vis, single crystal X-ray diffraction as well as other physical properties. The general formula of the prepared complexes is [Con(valp)m(L)z], (n = 1, 2 …; m = 1, 2, …; Z = 1, 2 …). The complexes [Co2(valp)4] (1), [Co(valp)2(2-ampy)2] (2) and [Co2(valp)4(quin)2] (3) showed different carboxylate coordination modes. The crystal structures of the complexes 2 and 3 were determined using single crystal X-ray diffraction. Kinetic studies of hydrolysis reactions of BNPP [bis-(p-nitrophenyl)phosphate] with complexes 2 and 3 were performed. The hydrolysis rate of BNPP was studied at different temperatures, pH and concentrations by UV–Vis spectrophotometric method. The results showed that the hydrolysis rate of BNPP was 7.70 × 102 L mol−1 s−1 for (3) and 2.60 × 10−1 L mol−1 s−1 for (2).

The complexes [Zn(phenylacetato)(2)(2-aminopyridin)(2)] (3), [Zn(phenylacetato)(2)(1,10-phenanthroline)]H2O (4), and [Zn(phenylacetato)(2)(2,9-dimethyl-1,10-phenanthroline)]0.5 H2O (5) were prepared and characterized by IR-, UV-Visible, H-1 and C-13 NMR spectroscopy, and single crystal X-ray diffraction. BNPP hydrolysis of the complexes and their parent nitrogen ligands showed that the hydrolysis rate of bis-(4-nitrophenyl) phosphate (BNPP) was 1.7x10(5)Lmol(-1)s(-1) for 3, 3.1x10(5)Lmol(-1)s(-1) for 4 and 4.3x10(4)Lmol(-1)s(-1) for 5. Antibacterial activities show the effect of complexation on activity against Gram-positive (S. epidermidis, S. aureus, E. faecalis, M. luteus and B. subtilis) and Gram-negative (K. pneumonia, E. coli, P. mirabilis and P. aeruginosa) bacteria using the agar well diffusion method. Complex 4 showed good activity against G- bacteria except P. aeruginosa, and against G+ bacteria except E. ferabis. Complex 5 showed no activity against G- bacteria, low activity against M. luteus and B. subtilis bacteria and high activity against S. epidemidis and S. aureus. Complex 3 did not show any activity against G- or G+ bacteria.

Metal carboxylate compounds with nitrogen‐ and/or oxygen‐donor ligands with various carboxylate coordination modes, monodentate, bidentate and bridging bidentate, have been shown to be important from biological and chemical aspects. Five zinc ion binary compounds, diaqua‐bis‐(2‐((E)‐5‐fluoro‐2‐methyl‐1‐(4‐(methylsulfinyl)benzylidene)‐1H–inden‐3‐yl)acetato)zinc(II) (1), aqua‐bis‐(2‐((E)‐5‐fluoro‐2‐methyl‐1‐(4‐(methylsulfinyl)benzylidene)‐1H–inden‐3‐yl)acetato)pyridin‐2‐aminezinc(II) (2), (2‐((E)‐5‐fluoro‐2‐methyl‐1‐(4‐(methylsulfinyl)benzylidene)‐1H–inden‐3‐yl)acetato) pyridin‐2‐ylmethanaminezinc(II) (2‐((E)‐5‐fluoro‐2‐methyl‐1‐(4‐(methylsulfinyl)benzylidene)‐1H–inden‐3‐yl)acetate) (3), bis‐(2‐((E)‐5‐fluoro‐2‐methyl‐1‐(4‐(methylsulfinyl)benzylidene)‐1H–inden‐3‐yl)acetato)‐1,10‐phenanthrolinezinc(II) (4) and bis‐(2‐((E)‐5‐fluoro‐2‐methyl‐1‐(4‐(methylsulfinyl)benzylidene)‐1H–inden‐3‐yl)acetato)‐1,10‐phenanthrolinezinc(II) (5), have been prepared and fully characterized. In addition, the complexes were evaluated for their antibacterial activity using the in vitro agar diffusion method against two Gram‐positive (Staphylococcus epidermidis, Staphylococcus aureus) and two Gram‐negative (Bordetella, Escherichia coli) bacteria and yeast species (Saccharomyces and Candida). Complex 5 showed reasonable activity against yeast. All compounds showed greater antibacterial activity against Gram‐positive than Gram‐negative bacteria. Results indicated that the efficiency of complex 5 in preventing the formation of β‐hematin was 67.6%. The efficiency of chloroquine as a standard drug was reported as 93%. Furthermore, the phosphatase activity of the Zn(II) complexes was studied and results indicated an effect of the zinc complexes on phosphatase activity.

This work reports synthesis, crystallographic, spectroscopic studies and biological activity of new cobalt(II) complexes with bioactive mixed sulindac and nitrogen-donor ligands. The crystal structures of complexes 1 and 4 were determined using single-crystal X-ray diffraction.In-vitro anti-bacterial activity of the prepared complexes and their parent ligands were investigated against different Gram-positive and Gram-negative bacteria using agar diffusion method

The complexes [Zn(methoxyacetate) 2 1,10-phenanthroline] 1 and [Zn 2 (phenylacetate) 4 (quinoline) 2 ] 2 , were prepared and characterized by IR-spectroscopy, UV–Visible spectroscopy, 1 H and 13 C NMR spectroscopy, single crystal X-ray diffraction. BNPP hydrolysis of the complexes and their parent nitrogen ligands were scanned, the results indicated that the hydrolysis rates of BNPP were 4.5 × 10 4 and 6.2 × 10 5 for ( 1 ) and ( 2 ), respectively. In addition, anti-bacterial activities were scanned to investigate the effect of complexation on their activity against Gram-positive ( S. epidermidis , S. aureus , E. faecalis , M. luteus and B. Subtilis ) and Gram-negative ( K. pneumonia , E. coli , P. Mirabilis and P. Aeruginosa ) bacteria using agar well-diffusion method. Complex 1 showed high activity against G − and G + bacteria except against E. faecalis and P. Aeruginosa . Complex 2 did not show any activity against G − or G + bacteria.

Complexes of [Zn(ibup)(2)(4,4'-bipy)](n) 1, [Zn(ibup)(2)(phen)] 2, [Zn(ibup)(2)(2,9-dmphen)] 3, [Zn(ibup)(2)(1,2-dmimidazole)(2)] 4, and [Zn(ibup)(2)(2-am-6-picoline)(2)] 5 (ibu=ibuprofen, 4,4-bipy=4,4'-bipypyridine, phen=1,10-phenanthroline, 2,9-dmephen=2,9-dimethyl-1,10-phenanthroline, 1,2-dmimidazole=1,2-dimethylimidazole, and 2-am-6-picoline=2-amino-6-picoline) were prepared and characterized. The crystal structure of 1 was determined by single-crystal X-ray diffraction. The in vitro anti-bacterial activities for the complexes against Gram-positive (Micrococcus luteus, Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Escherichia coli, Klebsiella pneumonia and Proteus mirabilis) bacteria were done using the agar well-diffusion method. Complexes 1-3 showed anti-bacterial activity against Gram-positive bacteria, while 4 and 5 did not exhibit anti-bacterial activity. Complexes 2 and 3 were selected for further studies. Complexation of zinc-ibuprofen with phen as in 2 decreased the anti-bacterial activity against most of the bacteria used. The complexation in 3 decreased the anti-bacterial activity in Gram-positive bacteria but for Gram-negative bacteria, the overall anti-bacterial activity of uncoordinated 2,9-dmphen was enhanced upon coordination with zinc ibuprofen.[GRAPHICS].

A nitrogen-based ligand (pyridine-2-yl-undecyl-amine) (1) was synthesized and used for the synthesis of a Zn(II) compound (dichloro-bis(pyridine-2-yl-undecyl-amine)zinc(II)) (2). Compound 2 was synthesized and characterized using IR, H-1 NMR, and C-13{H-1} NMR spectroscopy. The crystal structure of 2 was determined using single-crystal X-ray crystallography. The compound was tested for its anti-malarial activity using two methods, a semi-quantitative micro-assay and a previously self-developed quantitative in vitro method. Both methods were used to study the efficiency of 2 to inhibit the formation of the malaria pigment considered an important target of many anti-malarial drugs such as chloroquine and amodaquine. The efficiency of 2 to prevent the formation of -hematin was 71.4%. The efficiency of amodiaquine as a standard drug was reported at 93.8%.[GRAPHICS].

A series of complexes of Zn(II), [Zn-2(Indo)(4)] 1, [Zn-2(indo)(4)(pico)(2)] 2, [Zn(indo)(2)(apy)(2)] 3, [Zn(indo)(2) (ampy)] 4, [Zn(indo)(2)(phen)] 5, [Zn(indo)(2)(dmph)] 6, [Zn(indo)(2)(admp)(2)] 7, (indo = indomethacin, apy = 2-amino pyridine, dmph = 2,9-dimethyl-1,10-phenanthroline, pico = 3-picoline, ampy = 2-amino-methyl pyridine, phen = 1,10-phenanthroline, admp = 2-amino-4,6-dimethylpyrimidine) were synthesized and characterized using IR, UV-Vis, (HNMR)-H-1, C-13{H-1}NMR spectroscopic techniques in order to examine their binding coordination modes in addition to their biological activity. The crystal structures of complex 2 was determined by single crystal X-ray diffraction, showing binuclear complex with two 3-picoline groups one for each Zn(II) center, and four indomethacin molecules, two of them were bidentate chelating, one was bidentate bridging, and the other was monodentate terminal bridging. In-vitro anti-bacterial activities of the complexes were screened using agar diffusion method against two gram-positive bacteria (Staphylococcus aureus, Listeria monocytogenes) and two gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa). Most of the complexes showed anti-bacterial effects against P. aeruginosa, and S. aureus while they were inactive toward E. coli and L monocytogenes. Complexes 1-4 showed higher activity upon complexation against P. aeruginosa and S. aureus than their parent ligands. Complex 5 showed decreased activities upon complexation against all tested bacteria except against P. aeruginosa were it was inactive. Complex 6 showed decreased activity against S. aureus, but its activity was not affected by complexation against P. aeruginosa. Complex 7 showed higher activity against S. aurens, and no activity against P. aeruginosa. 2016 Elsevier Ltd. All rights reserved.

A series of novel complexes of Zn(II) [Zn(diclo)(2)(H2O)(2)] (1), [Zn(diclo)(2)(apy)(2)] (2), [Zn(diclo)(2)(dmph)](2) (3), [Zn-2(diclo)(4)(pico)(2)] (4), [Zn(diclo)(2)(ampy)] (5), [Zn(diclo)(2)(phen)] (6), [Zn(diclo)(2)(admp)(2)] (7) (diclo = diclofenac, apy = 2-amino pyridine, dmph = 2,9-dimethyl-1,10-phenanthroline, pico = 3-picoline, ampy = 2-aminomethyl pyridine, phen = 1,10-phenanthroline, admp = 2-amino-4,6-dimethylpyrimidine) were synthesized and characterized using IR, UV-Vis, H-1 NMR, C-13{H-1}NMR spectroscopic techniques as well as single crystal X-ray diffraction were used to characterize complexes (1), (2) and (3).In vitro anti-bacterial activities of the complexes were screened using agar diffusion method against two Gram-positive bacteria (Staphylococcus aureus, Listeria monocytogenes) and two Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa). Most of the complexes showed anti-bacterial effects against P. aeruginosa, and S. aureus while, but they were inactive toward E. coli and L. monocytogenes. Complexes (1), (2), (4), (5) and (7) showed higher activity upon complexation against P. aeruginosa, and S. aureus than their parent ligands. Complex (3) showed decreased activity against S. aureus upon complexation, but their activity against P. aeruginosa was not affected. Complex (6) showed decreased activity upon complexation against all tested bacteria; except P. aeruginosa where it was inactive. (C) 2016 Elsevier Ltd. All rights reserved.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Abstract Metal carboxylate complexes possess different carboxylate coordination modes, e.g. monodentate, bidentate, and bridging bidentate. Five Zn(II) complexes were prepared and characterized in order to examine their coordination modes in addition to their biological activity. The syntheses were started by preparation of [Zn(ibup)2(H2O)2] (1). Then, different nitrogen-donor ligands reacted with 1 to produce [Zn(ibup)2(2-ampy)2] (2), [Zn(ibup)(2-ammethylpy)] (3), [Zn(ibup)(2,2′-bipy)] (4), and [Zn2(ibup)4(2-methylampy)2] (5) (ibup = ibuprofen, 2-ampy = 2-aminopyridine, 2-ammethylpy = 2-aminomethylpyridine, 2,2′-bipy = 2,2′-bipyridine, 2-methylampy = 2-(methylamino)pyridine). IR, 1H NMR, 13C{1H}-NMR and UV–vis spectroscopies were used for characterization. The crystal structures of 2 and 5 were determined by single-crystal X-ray diffraction. Investigation of in vitro antibacterial activities for the complexes against Gram-positive (Micrococcus luteus, Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis) bacteria were done using agar well-diffusion method. Complex 1 showed antibacterial activity against Gram-positive bacteria. Complexes 2 and 3 did not exhibit antibacterial activity. Complex 4 showed antibacterial activity and was chosen for further studies to determine the inhibition zone diameter for different concentrations and to set the minimum inhibitory concentration. The antibacterial activity against most of the bacteria was minimized as a result of the complexation of zinc ibuprofen with 2,2′-bipy in 4.