: The unpolarized absorption and circular dichroism spectra of the fundamental vibrational transitions of the chiral molecule, 4-methyl-2-oxetanone, are calculated ab initio. Harmonic force fields are obtained using Density Functional Theory (DFT), MP2, and SCF methodologies and a 5S4P2D/3S2P (TZ2P) basis set. DFT calculations use the Local Spin Density Approximation (LSDA), BLYP, and Becke3LYP (B3LYP) density functionals. Mid-IR spectra predicted using LSDA, BLYP, and B3LYP force fields are of significantly different quality, the B3LYP force field yielding spectra in clearly superior, and overall excellent, agreement with experiment. The MP2 force field yields spectra in slightly worse agreement with experiment than the B3LYP force field. The SCF force field yields spectra in poor agreement with experiment.The basis set dependence of B3LYP force fields is also explored: the 6-31G* and TZ2P basis sets give very similar results while the 3-21G basis set yields spectra in substantially worse agreements with experiment. jg

Ab initio calculation of vibrational absorption and circular dichroism spectra using density functional force fields

Listeria monocytogenes is a Gram positive, aerobic, facultative anaerobic and nonacid fast bacterium, which can cause the disease listeriosis in both human and animals. It is widely distributed thoroughout the environment and has been isolated from various plant and animal food products associated with listeriosis outbreaks.

Contaminated ready-to-eat food products such as gravad and cold-smoked salmon and rainbow trout have been associated with human listeriosis in Sweden. The aim of this study was to analyse the occurrence and level of L. monocytogenes in
gravad and cold-smoked salmon (Salmo salar) products packed under vacuum or modified atmosphere from retail outlets in Sweden. Isolated strains were characterized by serotyping and the diversity of the strains within and between
producers were determined with PFGE (Pulsed-field gel electrophoresis). The characterized fish isolates were compared with previously characterized human strains.
L. monocytogenes was isolated from 11 (three manufacturers) of 56 products analysed. This included gravad salmon products from three manufacturers and cold-smoked salmon from one manufacturer. The highest level of L. monocytogenes found was 1500 cfu/g from a cold-smoked salmon product but the level was low (<100 cfu/g) in most of the products. Serovar 1/2a was predominant,
followed by 4b. Three products of gravad salmon harboured more than one serovar. PFGE typing of the 56 salmon isolates detected five Asc I types: four types were identical to human clinical strains with Asc I and one was identical and one was closely related to human clinical strains with Apa I. Isolation of identical or closely related L. monocytogenes strains from human clinical cases of listeriosis and gravad and cold-smoked salmon suggested that these kinds of products are possible sources of listeriosis in Sweden. Therefore, these products should be considered risk products for human listeriosis.

Listeria monocytogenes, a food-borne pathogen

Pyrazole and its derivatives are considered a pharmacologically important active scaffold that possesses almost all types of pharmacological activities. The presence of this nucleus in pharmacological agents of diverse therapeutic categories such as celecoxib, a potent anti-inflammatory, the antipsychotic CDPPB, the anti-obesity drug rimonabant, difenamizole, an analgesic, betazole, a H2-receptor agonist and the antidepressant agent fezolamide have proved the pharmacological potential of the pyrazole moiety. Owing to this diversity in the biological field, this nucleus has attracted the attention of many researchers to study its skeleton chemically and biologically. This review highlights the different synthesis methods and the pharmacological properties of pyrazole derivatives. Studies on the synthesis and biological activity of pyrazole derivatives developed by many scientists around the globe are reported.

Synthesis and Pharmacological Activities of Pyrazole Derivatives: A Review

Antibiotic and Chemotherapy

The reactive oxidizing species in the selective oxidation of methane to methanol in oxygen activated Cu-ZSM-5 was recently defined to be a bent mono(μ-oxo)dicopper(II) species, [Cu(2)O](2+). In this communication we report the formation of an O(2)-precursor of this reactive site with an associated absorption band at 29,000 cm(-1). Laser excitation into this absorption feature yields a resonance Raman (rR) spectrum characterized by (18)O(2) isotope sensitive and insensitive vibrations, νO-O and νCu-Cu, at 736 (Δ(18)O(2) = 41 cm(-1)) and 269 cm(-1), respectively. These define the precursor to be a μ-(η(2):η(2)) peroxo dicopper(II) species, [Cu(2)(O(2))](2+). rR experiments in combination with UV-vis absorption data show that this [Cu(2)(O(2))](2+) species transforms directly into the [Cu(2)O](2+) reactive site. Spectator Cu(+) sites in the zeolite ion-exchange sites provide the two electrons required to break the peroxo bond in the precursor. O(2)-TPD experiments with (18)O(2) show the incorporation of the second (18)O atom into the zeolite lattice in the transformation of [Cu(2)(O(2))](2+) into [Cu(2)O](2+). This study defines the mechanism of oxo-active site formation in Cu-ZSM-5.

Oxygen precursor to the reactive intermediate in methanol synthesis by Cu-ZSM-5

In vitro screening, homology modeling and molecular docking studies of some pyrazole and imidazole derivatives.

New thiazole, pyridine and pyrazole derivatives as antioxidant candidates: synthesis, DFT calculations and molecular docking study

The aim of this study is to investigate the inhibit ion efficiency of N 1 ,N 1 ,N 5 ,N 5 -tetrakis((3,5-dimethyl-1H-pyrazol-1- yl)methyl)naphthalene-1,5-diamine (BF5), for mild s teel corrosion in 1.0 M HCl solution. For this purp ose, weight loss, electrochemical impedance spectroscopy and po tentiodynamic measurements were realized. The effec t of BF5 on the mild steel corrosion was also studied by qua ntum chemical calculations. Increasing inhibitor co ncentration led to significant reduction in the corrosion rate of mild steel, with inhibitor efficiency value abov e 97%. The corrosion behavior of steel in 1.0 M HCl without an d with the inhibitor at various concentrations was studied at the temperature range of 308 - 343 K. Potentiodynamic p olarization showed that this inhibitor as mixed-typ e inhibitor. The Nyquist plots showed that increasing BF5 concen tration, charge-transfer resistance increased and d ouble-layer capacitance decreased, involving increased inhibiti on efficiency. The adsorption of BF5 on the mild st eel surface was well described by the Langmuir adsorption model .

Corrosion inhibition of mild steel by new N-heterocyclic compound in 1 M HCl: Experimental and computational study

Pyrazole derivatives have their own importance in aromatic organic heterocycle family. Application of these derivatives in chemistry and biology has attracted increasing interest occupy a unique place in field of medicinal chemistry due to their wide spectrum of biological activities. There are known for their anticancer, antiviral, antibacterial, antifungal, analgesic and anti-inflammatory and activities and so on. Due to the importance of this chemical skeletons, the present review reports the recent progress (2010-2016) on the biological activities of some monodentate, bidentate, tridentate and tetradente compounds based on pyrazole moieties and containing NCN bonds which connecting between the pyrazole and amine unit.

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Pyrazole Derivatives with NCN Junction and their Biological Activity: AReview

A new library of N,N,N’,N’ -tetradentate pyrazoly compounds containing a pyrazole moiety was synthesized bythe condensation of (3,5-dimethyl-1H-pyrazol-1-yl)methanol 2a or (1H-pyrazol-1-yl)methanol 2b with a series of primarydiamines in refluxed acetonitrile for 6h. The antifungal activity against the budding yeast Saccharomyces cerevisiae, aswell as the antibacterial activity against Escherichia coli of these new tetradentate ligands were studied. We found thatthese tetradentate ligands act specifically as antifungal agents and lack antibacterial activity. Their biological activities dependon the nature of the structure of the compounds.

Farid Abrigach

Papers

In vitro screening, homology modeling and molecular docking studies of some pyrazole and imidazole derivatives.

New thiazole, pyridine and pyrazole derivatives as antioxidant candidates: synthesis, DFT calculations and molecular docking study

Corrosion inhibition of mild steel by new N-heterocyclic compound in 1 M HCl: Experimental and computational study

Pyrazole Derivatives with NCN Junction and their Biological Activity: AReview

New N,N,N',N'-tetradentate Pyrazoly Agents: Synthesis and Evaluation of their Antifungal and Antibacterial Activities.