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Nanopowders of copper molybdate, α-CuMoO4, were prepared through calcination of an oxalate complex in static air at 550 °C. The oxalate complex was investigated by Fourier transform infrared spectroscopy and thermal gravimetric analysis. The as-prepared copper molybdate was characterized by X-ray powder diffraction and the Brunauer–Emmett–Teller technique. Its catalytic effectiveness was verified by the oxidation reaction of methylene blue (MB) with hydrogen peroxide (H2O2) and by the reduction reaction of para-, meta-, and ortho-nitrophenol. The prepared copper molybdate exhibited exceptionally high catalytic performance of the oxidation of methylene blue dye and of the reduction reaction of the three isomers of nitrophenol to the three corresponding aminophenol isomers. The evolution of the catalytic activity was controlled by utilizing UV-Vis absorption spectroscopy.

Abstract Epoxy nanocomposite coatings are an essential way to protect petroleum storage tanks from corrosion. For this purpose, the new nanocomposite epoxy coatings (P-M/epoxy composites) have been successfully designed. The P-M/epoxy composites are based on the metal vanadium oxy-phosphate M0.5VOPO4 (where M = Mg, Ni, and Zn). The function of P-M/epoxy composites as anti-corrosion coatings was explored using electrochemical and mechanical tests. Using electrochemical impedance spectroscopy (EIS), it has been noticed that the pore resistance and polarization resistance of the P-M/epoxy composites remain higher as compared to the neat epoxy. The P-M/epoxy composites have the greatest impact on the cathodic dis-bonded area and water absorption. Besides, P-M/epoxy composites exhibit a very high order of mechanical properties. Further, Mg0.5VOPO4 has the greatest effect on the anti-corrosion properties of epoxy coating followed by Zn0.5VOPO4 and Ni0.5VOPO4. All these properties lead to developing effective anti-corrosion coatings. Thus, the net result from this research work is highly promising and provides a potential for future works on the anti-corrosion coating.

Background:Ceratonia siliqua L. (Carob tree) is a Mediterranean evergreen, well known for its medicinal properties. The different parts of Carob were proven to exert antidiabetic, antibacterial, antifungal, and antiproliferative effects. Hence, the present paper aims to validate the positive correlation between the high antioxidant activity of carob seed peels and the improvement of negative symptoms of schizophrenia. Materials & Methods: The antioxidant activity was carried out using the β-carotene test. Methionine and carob seed peels (CSP) extracts (50 and 100 mg/kg) were orally administrated to mice for a week. After administration, behavioral tests were assessed using the Y-maze, elevated plus maze, and forced swimming tests, as well as the novel object recognition task. Furthermore, the oxidative stress status was evaluated by analyzing the levels of the antioxidant enzymes: Superoxide dismutase (SOD), glutathione peroxidase (GPx), and malondialdehyde levels (MDA). Results: Both extracts exhibited remarkable antioxidant activity and showed antibacterial effect against Gram-positive bacteria tested (Bacillus subtilis and Staphylococcus aureus) and against Pseudomonas aeruginosa (Gram-negative). Therefore, Escherichia coli was very resistant. The behavioral tests proved the efficacy of CSP in enhancing the cognitive impairment of animal models of schizophrenia. Hence, the stated correlation between oxidative stress and schizophrenia was confirmed by the increased SOD and GPx activities and the decreased MDA level. Conclusions: The present study gave further confirmation of the potential correlation between oxidative stress and the development of psychiatric disorders and highlighted the use of natural antioxidants, especially Ceratonia siliqua L. in the improvement of cognitive impairment in the dementia of schizophrenia.

The antioxidant activity of Carob seed peels extracts, obtained by sequential extraction with different polarities of solvents, was evaluated by using different in vitro assays: diphenyl-picryl-hydrazyl (DPPH) radical scavenging capacity, ferric reducing antioxidant power activity and phosphomolybdenum assay. The effect of Carob seed peels extracts on mood disorders and anxiety was accessed by the y-maze, elevated plus maze and forced swimming tests. The results showed that the phenolic compounds and the antioxidant capacity varied significantly with the nature of solvent of extraction. Both acetone and ethyl acetate extracts enhanced the spontaneous alternation in the Y-maze task and the time spent on open arms in the elevated plus maze task. However, the acetonic extract proved its efficacy in the forced swimming test. Thus, the carob seed peel revealed a strong antioxidant activity and proved its potential to open a new mechanistically approaches of antidepressant and anxiolytic drug development.

The title compound, 4,4-bis(hydroxymethyl)-2-phenyl-2-oxazoline 2, a well-known substance, was resynthesized in high yields through a conventional method. The structure of compound 2 was characterized for the first time by a single-crystal X-ray structure determination. The compound was further established through NMR spectroscopy (1D and 2D). In the molecular packing, two molecules of 4,4-bis(hydroxymethyl)-2-phenyl-2-oxazoline interact through H-Bonds to define “dimers” in which phenyl groups interact especially using π…π contact.

A novel hybrid cobalt phosphite, (H2DAB)[Co(H2PO3)4] 2H2O, was synthesized by using a slow evaporation method in the presence of cobalt nitrate, phosphorous acid, and 1,4-diaminobutane (DAB = 1,4-diaminobutane) as a structure-directing agent. Single-crystal X-ray diffraction analysis showed that the compound crystallizes in the triclinic system (space group P-1(n.2)) with the following unit cell parameters (Å, °) a = 5.4814 (3), b = 7.5515 (4), c = 10.8548 (6), α = 88.001 (4), β = 88.707 (5), γ = 85.126 (5), and V = 447.33 (4) Å3. The crystal structure is built up from corner-sharing [CoO6] octahedra, forming chains parallel to [001], which are interconnected by H2PO3− pseudo-tetrahedral units. The diprotonated cations, residing between the parallel chains, interact with the inorganic moiety via hydrogen bonds, thus leading to the formation of the 3D crystal structure. The Fourier transform infrared spectrum showed characteristic bands corresponding to the phosphite group and the organic amine. The thermal behavior of the compound mainly consisted of the loss of its organic moiety and the water molecules. The biological tests exhibited significant activity against Candida albicans and Escherichia coli strains at different concentrations, while less inhibitory activity was pronounced against Staphylococcus epidermidis and Saccharomyces cerevisiae, and in the case of multi-cellular organisms, no activity against the nematode model Steinernema feltiae was detected.

Heterocyclic ligands and their metallic complexes are biologically active materials [...]

Stachys mouretii leaf extracts were analyzed for total phenolic and flavonoid contents. These components are responsible for antioxidant activity. The plant material was collected in April 2018 at the forest of Talasemtane in the region of Ouazzane, Morocco. Dried and crushed leaves were subjected to sequential extraction with hexane, ethyl acetate, and methanol in order of increasing polarity. The amount of total phenolic and flavonoid content were determined with Folin–Ciocalteu and aluminum chloride (AlCl3) reagents, respectively. For the total phenolic content, gallic acid was used as a standard compound and the results were expressed as µg/mL gallic acid equivalent (GAE), while for the total flavonoids, quercetin was used as a standard compound and the results were expressed as mg/mL quercetin equivalent (QE). The total phenolic content of Stachys mouretii leaf extracts varied from 14.13 to 26.91 µg/mL GAE and the total flavonoid content ranges from 0.04 to 0.08 mg/mL QE. The maximum phenolic and flavonoid contents were found in the ethyl acetate extract. The findings suggested that phytochemicals present in Stachys mouretii are potentially beneficial as therapeutic and antioxidative agents in pharmaceuticals, foods and other related industries.

A new dihydroisoquinoline-N-oxide alkaloid 1 together with the previously known methyl 4-hydroxybenzoate 2 were isolated for the first time from the seeds of Calycotome villosa subsp. intermedia. Their structures were elucidated by extensive spectroscopic analysis and in the case of the new alkaloid 1-hydroxymethyl-6,7-dimethoxy-3,4-dihydroisoquinoline-N-oxide 1 by X-ray diffraction analysis.

Two tetrahydroisoquinoline alkaloids were extracted from the alkaloid fraction of a methanol extract of the seeds of Calycotome Villosa Subsp. intermedia. Their structures were established as (R)-1-hydroxymethyl-7-8-dimethoxy-1,2,3,4-tetrahydro- isoquinoline (1) and (S)-7-hydroxymethyl-2-3-dimethoxy-7,8,9,10-tetrahydroisoquinoline chloride (2) by spectroscopic techniques and X-ray diffraction analysis.

The known flavonoid chrysin-7-O-(β-D-glycopyranoside) (chrysin glucoside,1) as a major fraction and a new glycoside flavone, chrysin-7-O-β-D-[(6â€Â-acetyl)glycopyranoside] (2) were isolated from the flowers and leaves of CalycotomeVillosa Subsp. Intermedia, They were identified by UV-Vis, 1R, 1H-, 13C-NMR and ESI-MS.

The asymmetric unit of the title molecular salt [systematic name: 1,4,8,11-tetraazacyclotetradecane-1,8-diium bis(3-carboxyprop-2-enoate)], C10H26N42+·2C4H3O4−, contains two half-cations (both completed by crystallographic inversion symmetry) and two maleate anions. The cyclam macrocycles adopt trans-III conformations, supported by two intramolecular N—H...O hydrogen bonds. The O-bonded H atom of each maleate ion is disordered over two positions with an occupancy ratio of 0.61 (5):0.39 (5): each one generates an intramolecular O—H...O hydrogen bond. In the crystal, the cations are linked to the anions by N—H...O hydrogen bonds, generating [001] chains.

The asymmetric unit of the title compound, C12H17NO3, contains two molecules with different conformations. It is a polymorph of the monoclinic form [El Antri et al. (2004). Molecules, 9, 650–657]; the samples were crystallized at different temperatures from the same solvent. In both structures, molecules are linked by O—H...N hydrogen bonds, forming chains. The conformations of the chains and their packing differ markedly in the two polymorphs.

In the title compound, K2Co(H2P2O7)2·2H2O, the octahedrally coordinated Co2+ ion lies on an inversion centre. Two bidentate dihydrogendiphosphate anions form the equatorial plane of the [CoO6] octahedron which is completed by two water molecules in axial positions. This results in isolated {Co(H2O)2[H2P2O7]2}4− entities linked into a three-dimensional network through K—O bonds and O—H...O hydrogen-bonding interactions involving the dihydrogendiphosphate anions and water molecules. The dihydrogendiphosphate anion, (H2P2O7)2−, is bent and shows an almost eclipsed conformation.

The title compound, (C10H28N4)[MnCl4(H2O)2]Cl2·2H2O, consists of isolated octahedral [MnCl4(H2O)2]2− anions, tetraprotonated 1,4,8,11-tetraazoniacyclotetradecane cations, chloride anions and water molecules connected by a network of hydrogen bonds. The MnII atom is situated on an inversion centre, and the 1,4,8,11-tetraazoniacyclotetradecane cation is located on a mirror plane.

The crystal structure of the title compound, C7H10N+·H2PO3−, has been reported previously by Sabounchei & Naghipour [Asian J. Chem. (2003), 15, 1677–1686]. A new look at this compound has revealed doubling of the unit cell. The asymmetric unit consists of two 4-methylanilinium cations and two dihydrogen phosphite anions. The crystal structure is built upon alternating layers of organic cations and dihydrogen phosphite anions stacked along c. The organic layer is stabilized by C—H...π interactions. Weak aromatic π–π stacking interactions with centroid–centroid distances of 4.6147 (12), 4.6917 (12), 4.6932 (13) and 4.8366 (13) Å are also observed in the structure. The dihydrogen phosphite anions are linked by O—H...O hydrogen bonds into chains running parallel to the a-axis direction. These chains are connected to the cation layer by N—H...O hydrogen bonds.

Dinickel(II) silicon bis[diphosphate(4−)], Ni2Si(P2O7)2, is isotypic with other phosphates of the formula M2Si(P2O7)2 (M = Co, Cd). All atoms except Si (site symmetry 2) are found in general positions. Ni2O10 dimers formed from edge-sharing NiO6 octahedra are linked by corners and O—P—O bridges, forming slabs parallel to (100), which are in turn interconnected by O—Si—O contacts.

In the title compound, Pb2(HPO3)(NO3)2, the two distinct Pb2+ ions (both with site symmetry m) adopt irregular PbO10 coordination polyhedra. The structure is completed by two distinct nitrate groups (in which one O atom and the N atom have m site symmetry for both ions) and an HPO32− anion (in which one O atom and the P and H atoms have m site symmetry). The connectivity of the PbO10, NO3 and HPO3 units in the crystal structure results in a three-dimensional network.

The framework of the title compound, {(NH3CH2CH2NH3)[CdCl4]}n, is built upon layers parallel to (100) made up from corner-sharing [CdCl6] octahedra. NH3CH2CH2NH32+ cations are situated between the layers and are linked to the layers via an N—H...Cl hydrogen-bonding network. The Cd atom is located on an inversion centre and the coordination environment is described as highly distorted octahedral.

The title compound, Cs2Mg(H2P2O7)2·2H2O, is isostructural with the related known isoformular phosphates. The crystal framework consists of corner-sharing MgO6 and H2P2O7 polyhedra, leading to tunnels parallel to the b-axis direction in which Cs+ ions are located. The H2P2O7 unit shows a bent eclipsed conformation. The Mg2+ ion lies on an inversion center. The water molecules form hydrogen bonds to O atoms of two different dihydrogenphosphate ions, which are further hydrogen bonded to symmetry-equivalent dihydrogenphosphate ions.

The title compound, NH4YbP2O7, crystallizes in the KAlP2O7 structure type and consists of distorted YbO6 octahedra and bent P2O74− diphosphate units forming together a three-dimensional network. There are channels in the structure running along the c axis, where the NH4+ cations are located. They are connected via N—H...O hydrogen bonds to the terminal O atoms of the diphosphate anions.

Small molecules have been shown to be potent and selective probes to understand cell physiology. Here, we show that imidazo[1,2-a]pyridines and imidazo[1,2-a]pyrimidines compose a class of compounds that target essential, conserved cellular processes. Using validated chemogenomic assays in Saccharomyces cerevisiae, we discovered that two closely related compounds, an imidazo[1,2-a]pyridine and -pyrimidine that differ by a single atom, have distinctly different mechanisms of action in vivo. 2-phenyl-3-nitroso-imidazo[1,2-a]pyridine was toxic to yeast strains with defects in electron transport and mitochondrial functions and caused mitochondrial fragmentation, suggesting that compound 13 acts by disrupting mitochondria. By contrast, 2-phenyl-3-nitroso-imidazo[1,2-a]pyrimidine acted as a DNA poison, causing damage to the nuclear DNA and inducing mutagenesis. We compared compound 15 to known chemotherapeutics and found resistance required intact DNA repair pathways. Thus, subtle changes in the structure of imidazo-pyridines and -pyrimidines dramatically alter both the intracellular targeting of these compounds and their effects in vivo. Of particular interest, these different modes of action were evident in experiments on human cells, suggesting that chemical-genetic profiles obtained in yeast are recapitulated in cultured cells, indicating that our observations in yeast can: (1) be leveraged to determine mechanism of action in mammalian cells and (2) suggest novel structure-activity relationships.

The crystal structure of the title compound, C15H13N3O, consists of columns of molecules that are interconnected by N—H...N hydrogen bonds in the direction of the b axis. The torsion angle between the imidazo[1,2-a]pyridine ring system and the phenyl ring is 9.04 (5)°.

In the title compound, C14H10N2O, the dihedral angle between the imidazo[1,2-a]pyridine and phenyl rings is 28.61 (4)° The molecules are connected into broad chains parallel to the a axis by weak C—H...O and C—H...N hydrogen bonds. The linking of the ribbons is provided by π–π stacking interactions between neighbouring pyridine rings, with a centroid–centroid distance of 3.7187 (7) Å.

The Tb atom of the title compound, TbHP2O7·4H2O, is coordinated by the O atoms of three symmetrically independent water molecules and by five O atoms belonging to HP2O7− groups. The TbO8 polyhedra are interconnected by the diphospate anions, forming a three-dimensional network which is additionally stabilized by O—H...O hydrogen bonding between water molecules and O atoms of the HP2O7− anions. Uncoordinated water molecules are situated in channels and are connected via hydrogen bonds with the framework.

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