HgO/I2 as an Efficient Reagent for the Oxidative Aromatization of Hantzsch 1-NH, 4-Dihydropyridines under Mild and Heterogeneous Conditions

A variety of Hantzsch 1-NH, 4-dihydropyridines were efficiently aromatized to the corresponding pyridine derivatives by treatment with HgO/I2 reagent in dichloromethane under mild and  heterogeneous conditions in good to excellent yields at room temperature. The products were separated by simple filtration and evaporation of the solvent.KEYWORDS: HgO/I2, Hantzsch 1,4-dihydropyridine, aromatization, heterogeneous

Structural investigation of a new cadmium coordination compound prepared by sonochemical process: Crystal structure, Hirshfeld surface, thermal, TD-DFT and NBO analyses

The final publication is available at Elsevier via https://doi.org/10.1016/j.ultsonch.2018.11.024. © 2019. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/A new nanostructured cadmium complex containing a tridentate Schiff base ligand was sonochemically synthesized and characterized by XRPD, FT/IR, NMR, and single crystal X-ray crystallography. Structural data showed that cadmium(II) ion is surrounded by three nitrogen atoms of Schiff base ligand and two iodide anions. The crystal packing was contained the intermolecular interactions such as CH⋯O, CH⋯I and π⋯π interactions organizing the self-assembly process. Hirshfeld surfaces and corresponding fingerprint plots have been used for investigation of the nature and proportion of interactions in the crystal packing. FT/IR, NMR and XRD data were in agreement with the X-ray structure and confirm the phase purity of the prepared sample. The molecular structure of the complex was optimized by density functional theory (DFT) calculation at the B3LYP/LANL2DZ level of theory and the results were compared with experimental ones. For more concise study of structure and spectral aspects of the complex, natural bond orbital (NBO) analysis and time-dependent density functional theory (TD-DFT) have been also performed. Thermal stability of the cadmium iodide complex was investigated by thermogravimetric analysis (TGA). Finally, cadmium oxide nanoparticles was prepared by direct calcination of CdLI2 complex as a new precursor.Partial support of this work by Yasouj University is appreciated

N,N′-Bis[(2-hydroxy­phen­yl)(phen­yl)methyl­idene]propane-1,2-diamine

In the the title compound, C29H26N2O2, two strong intra­molecular O—H⋯N hydrogen bonds involving the hydr­oxy and imine groups generate S(6) ring motifs. The dihedral angles between the pairs of terminal benzene rings are 89.8 (2) and 87.8 (2)°

Inhibition of Biofilm Formation, Quorum Sensing and Infection in Pseudomonas aeruginosa by Natural Products-Inspired Organosulfur Compounds

Using a microplate-based screening assay, the effects on Pseudomonas aeruginosa PAO1 biofilm formation of several S-substituted cysteine sulfoxides and their corresponding disulfide derivatives were evaluated. From our library of compounds, S-phenyl-L-cysteine sulfoxide and its breakdown product, diphenyl disulfide, significantly reduced the amount of biofilm formation by P. aeruginosa at levels equivalent to the active concentration of 4-nitropyridine-N-oxide (NPO) (1 mM). Unlike NPO, which is an established inhibitor of bacterial biofilms, our active compounds did not reduce planktonic cell growth and only affected biofilm formation. When used in a Drosophila-based infection model, both S-phenyl-L-cysteine sulfoxide and diphenyl disulfide significantly reduced the P. aeruginosa recovered 18 h post infection (relative to the control), and were non-lethal to the fly hosts. The possibility that the observed biofilm inhibitory effects were related to quorum sensing inhibition (QSI) was investigated using Escherichia coli-based reporters expressing P. aeruginosa lasR or rhIR response proteins, as well as an endogenous P. aeruginosa reporter from the lasI/lasR QS system. Inhibition of quorum sensing by S-phenyl-L-cysteine sulfoxide was observed in all of the reporter systems tested, whereas diphenyl disulfide did not exhibit QSI in either of the E. coli reporters, and showed very limited inhibition in the P. aeruginosa reporter. Since both compounds inhibit biofilm formation but do not show similar QSI activity, it is concluded that they may be functioning by different pathways. The hypothesis that biofilm inhibition by the two active compounds discovered in this work occurs through QSI is discussed

Solid phase extraction method for selective determination of Pb(II) in water samples using 4-(4-methoxybenzylidenimine) thiophenole

A sensitive and selective extractive preconcentration procedure for the determination of traces of lead in water samples has been developed. An alumina-sodium dodecyl sulfate (SDS) coated modified with 4-(4-methoxybenzylidenimine) thiophenole (MBITP) was used for preconcentration and determination of Pb(II) by flame atomic absorption spectrometry. Lead was adsorbed quantitatively on modified column due to its complexation with MBITP and quantitatively eluted using 5 mL 1 mol L-1 nitric acid in acetone. The effects of parameters such as pH, amount of solid phase, amount of MBITP, flow rate, type and concentration of eluting agent were examined. The effect of interfering ions on the determination of Pb(11) was also investigated. The response of proposed method is linear in the concentration range 0.05-1.2 mu g mL(-1) of Pb(II). The limit of detections (3S.D.(b)/m, n = 4) and relative standard deviations (n = 11) are 1.6 ng mL(-1) and 0.9%, respectively. The presented procedure was successfully applied for determination of lead content in real samples such as river, spring, waste and drinking water. (c) 2006 Elsevier B.V. All rights reserved

Chemical Modification of Activated Carbon and Its Application for Solid Phase Extraction of Copper(II) and Iron(III) Ions

Powder activated carbon surface (AC) was grinded and modified and altered procedure thorough a facile and easy chemical reaction to appearance of 2-((3silylpropylimino)1-methyl) phenol (AC- (SPIMP)). Subsequently, this novel sorbent efficiently applied for the extraction and preconcentration of some metal ions from real samples. Preliminary the influences of variables such as pH, amounts of reagents and porous AC, eluting solution conditions (type and concentrations), sample volume and influence of interference of many ions on the analytes recoveries was studied and optimized. This new sorbents property including pore size, pore volume and surface properties was evaluated and monitored by BET, while structure and homogeneously of sorbent was identified by SEM. The surface modification was traced by FT-IR as powerful and strong identification techniques. The proposed sorbent has high surface area(>1317.1346 m2 g-1) and small pore size