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A new complex formed from the reaction of benzene-1,2,4,5-tetracarboxylic dianhydride with zinc(II) acetate dihydrate was synthesized and characterized by single-crystal X-ray diffraction, thermal analysis (TGA), and density functional theory (DFT). [C10H4O8][Zn(H2O)6] (1), crystallized in a monoclinic system with space group P2/m. Theoretical modeling was performed at the DFT/B3LYP computational level with 6–311 G(d,p) and LanL2DZ basis sets. The Zn(II) is six-coordinate, forming an ideal octahedral geometry. A Hirshfeld surface analysis of the complex indicated that H···O/O···H contacts contribute to 47.8% of the crystal packing. The stability of 1 was investigated by determining the global chemical reactivity descriptors (GCRD). The nonlinear optical (NLO) behavior was investigated by analyzing the dipole moment, polarizability, and first-order hyperpolarizability (μ, α and β) via a theoretical approach, indicating that 1 has important nonlinear optical properties. A molecular docking study shows binding of 1 on the active site of receptors from human cyclooxygenase-2 enzyme (PDB code: 5IKT) and Escherichia coli MenB (PDB code: 3T88). [ABSTRACT FROM AUTHOR]

This current work describes the preparation of MgO‐SBA‐15 catalysts by ultrasonic method, and it is characterized by the different analysis techniques of XRD, BET, SEM, and IRTF. In order to find out an application for this mesoporous material, MgO/SBA‐15 was used as a heterogeneous catalyst in the one‐pot synthesis of pyrano[3,2‐c]chromenes derivatives isolated at room temperature reaction according to green chemistry criteria. To enhance these derivatives, a spectroscopic study of molecular fluorescence properties was carried out as well as an identification analysis by nuclear magnetic resonance and FTIR was used. Furthermore, biological activity experiment is also carried out, from where the obtained test results were satisfactory for AC09, AC05, and AC10 compounds and they are checked after computation by molecular modeling. [ABSTRACT FROM AUTHOR]

The transformations of (E)-3-[3-(2-hydroxyaryl)-3-oxoprop-1 -en-1 -yl]chromones in the presence of methylhydrazine and aromatic bisnucleophiles are described. The reactions generally lead to chro-mone ring transformation via pyrone ring-opening and heterocycliza-tion to give novel diazoles and (Z)-3-aminomethylenechromanones, respectively. Piperazine catalyzes chromanone ring closure of the starting substrate to afford chromone-chromanone dyads. [ABSTRACT FROM AUTHOR]

Cystic echinococcosis, an endemic zoonosis in Algeria, is caused by the development of the helminth Echinococcus granulosus. Surgery remains the main treatment despite inducing relapse and several adverse reactions. In this context, natural scolicidal agents seem to be promising tools to overcome these reactions. In our study, we evaluated the phytochemical contents, antioxidant activity and scolicidal effect of Atriplex halimus. In this context, the aqueous extract from AH leaves (AHE) was subjected to preliminary phytochemical screening by HPLC. The in vitro antioxidant activity was determined by DPPH test. The cytotoxicity of AHE was evaluated in murine peritoneal macrophages and cell viability was examined by MTT assay. Moreover, different concentrations of AHE (20, 40, 50, 60 and 100 mg/ml) were tested on E. granulosus protoscoleces (PSC) cultures, during different times of incubation (15, 30, 60, 90, 120 and 180 min). The viability was evaluated by eosin exclusion test. The morphological and ultrastructural damages were evaluated by SEM. Our results indicate that total phenolic and flavonoids contents were 37.93 μg of Gallic acid equivalent per mg of extract (GAE/mg E) and 18.86 μg of Quercetin equivalent per mg (QE/mg E) respectively. Furthermore, AHE has an antioxidant activity with an IC50 of 0.95 mg/ml. Interestingly, the extracts did not exhibit any cytotoxic effect against murine peritoneal macrophages. Moreover, our study indicated a significant scolicidal activity time- and dose-dependent. At 60 and 100 mg/ml; and after 120 min of incubation; the mortality rate was 99.36 and 100%, respectively. The parasite's tegument is one of the plant's targets as demonstrated by SEM. Our findings show the benefits of Atriplex halimus extract as a new promising scolicidal tool in hydatid cyst treatment. [Display omitted] • Phytochemical composition of Atriplex halimus aqueous extract. • Atriplex halimus has no cytotoxic effect on murine peritoneal macrophages • Antioxidant activity of Atriplex halimus aqueous extract. • In vitro scolicidal activity of Atriplex halimus extract: morphological and ultrastructural damage. [ABSTRACT FROM AUTHOR]

A one-pot synthesis of a novel series of chromeno-imidazopyridinone derivatives from 3-[(2-hydroxyphenyl)-3-oxoprop-1-en-1- yl]chromones and ethane-1,2-diamine at room temperature under catalyst- free conditions has been successfully developed. This approach involves a tandem aza-Michael addition reaction, a chromone-to-chromanone rearrangement, and a heterocyclization sequence, leading to chromeno-imidazo-pyridinone polyheterocycles. The structure and absolute configurations of the new compounds were elucidated by a combination of 1D- and 2D-NMR analyses and single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

We report an efficient one-pot synthesis of a novel series of chromenopyridodiazepinone polyheterocycles by a catalyst-free nucleophilic addition of ethane-1,2-diamine to (E,E)-3-[3-(2-hydroxyphenyl)- 3-oxoprop-1-en-1-yl]-2-styrylchromones at room temperature under mild conditions. The reaction proceeds by a tandem process involving 1,4- and 1,6-aza-conjugate additions of one amino group of ethane- 1,2-diamine to the α,β-unsaturated (3-oxoprop-1-en-1-yl) and the α,β,γ,δ-diunsaturated (2-styrylchromone) carbonyl system of the precursor, followed by imine condensation of the remaining amino group to generate the chromenopyridodiazepinone polyheterocycle. All compounds were characterized by means of one- and two-dimensional NMR spectroscopy and single-crystal X-ray crystallography. [ABSTRACT FROM AUTHOR]

An exo-selective one-pot synthesis of novel spiro[cyclohexanone-pyrandione] derivatives through two sequential organobase-catalysed 1,4-conjugate additions of pyran-2,4-dione precursors on diarylideneacetone derivatives is described. The resulting 7,11-diaryl-2-oxaspiro[5.5]undec-3-ene-1,5,9-triones were obtained as a 2 : 1 mixture of exo- and endo-diastereomers and adopt a meso-form due to the bilateral symmetry existing in the scaffold. Chiral-HPLC, NMR and single-crystal X-ray diffraction (including synchrotron data) have been used to elucidate the spiro[cyclohexanone-pyrandione] structure, showing therefore the exo/endo-diastereomers obtained in a meso-form, the cis-7,11-diaryl configuration (equatorial position) and different conformational changes in the cyclohexanone skeleton both in liquid and solid states. DFT studies proved the exo-stereoselectivity of the reaction by determining the exo/cis equatorial–equatorial configuration as the most thermodynamically stable form of our spiro[cyclohexanone-pyrandione] skeleton, while the structural substitution has no effect. [ABSTRACT FROM AUTHOR]

• New thiazole derivatives from natural product (Ammodaucus leucotrichus and Cuminum cyminum) were hemi-synthesized. • Chemical characterization of the obtained compounds was performed using FTIR, 1D and 2D NMR. • DFT calculation study confirmed the structural stability of the obtained compounds. • New thiazole derivatives exhibited moderate antioxidant activity, while their antibacterial one was much more interesting against some bacterial strains. • Molecular docking study revealed that the new thiazole derivatives can be good candidates to inhibit TNF-α. This paper reports the hemi-synthesis of a new thiazole derivatives from 3-allylrhodanine under green chemical conditions (solvent free and ambient temperature). Two targeted molecules: perillaldehyde and cuminaldehyde from essential oils of Ammodaucus leucotrichus Coss. & Dur. and Cuminum cyminum L. were used. Thiazole derivatives (HRP11, 12) were obtained and characterized by FTIR, 1H NMR, 13C NMR, 2D NMR. In addition, stereochemistry of HRP11, 12 was characterized by using 2D NMR and their structural stability was confirmed by DFT calculation. Furthermore, the new products were screened for their in vitro biological activity and in silico interaction with TNF-α by using molecular docking study. A moderate antioxidant activity was found for the two obtained products evaluated by DPPH and ABTS radical scavenging techniques. Against all odds, HRP12 revealed an interesting antibacterial activity against Escherichia coli, Citrobacter freundii , and Salmonella typhimurium. Thereby, a molecular fluorescence spectroscopy was carried out to compare the fluorescence of gentamicin and that of HRP11, 12. Molecular docking performed on the Tumor Necrosis Factor (TNF-α) demonstrated sensitivity towards the thiazole derivatives obtained. [Display omitted] [ABSTRACT FROM AUTHOR]

An abstract of the article "Actions of Bisnucleophiles on (E)-3-[3-(2-Hydroxyaryl)-3-oxoprop-1-en-1-yl]chromones: Versatile Transformation into Oxygen- and Nitrogen-Containing Heterocycles" by Ridha Hassaine and colleagues is presented.