Publications

CCDC 845505: Experimental Crystal Structure Determination

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.

Erratum: Bioactive C15 Acetogenins from the Red Alga Laurencia obtusa

Complexity of the Sequence of some Families of Graphs Based on Tridiminished icosahedron Graph

Tridiminished icosahedron graph is one of nonahedral graphs. In this work, using knowledge of difference equations we drive the explicit formulas for the number of spanning trees in the sequence of some new families of graphs of average degree four based on Tridiminished icosahedron graph by electrically equivalent transformations and rules of weighted generating function. Finally, we compare the entropy of our graphs with other studied graphs with average degree being 4.

Preparation of Styrene-Butadiene Rubber (SBR) Composite Incorporated with Collagen-Functionalized Graphene Oxide for Green Tire Application

Styrene-butadiene rubber (SBR) is a synthetic polymer primarily used in the tire industry, due to its good collaborative properties with additives and fillers. In the present work, we aim to synthesize an SBR composite reinforced with graphene oxide filler to be made biodegradable. In composite preparation, we fabricated styrene-butadiene rubber/graphene oxide/collagen (SBR/GO/COL) composites by adding a biodegradable biomolecule of elastin collagen fillers at 1.5 wt% and 2.5 wt%. Those prepared SBR/GO/COL composites, along with pure SBR and SBR/GO as control samples, were characterized using advanced analysis techniques, and their biodegradability was also evaluated. From microscopy examination results, the morphology of pure SBR had been improved after the addition of GO for SBR/GO composite by revealing a compact structure with a smoother surface. As for the SBR/GO/1.5COL sample, the 1.5 wt% COL filler was found to be effectively embedded in the SBR/GO matrix. However, the 2.5 wt% COL amount led to the formation of an aggregated structure in the SBR/GO/2.5COL sample due to the unreacted interface between COL filler and SBR/GO. The porosity had also been improved for SBR/GO/1.5COL sample, imparting it with a surface area suitable for tires in the automobile industry. From elemental analysis, the presence of nitrogen was detected for the collagen-filled SBR composite, proving the successful incorporation of collagen fibrils. The physicochemical analysis also detected a trace of graphene oxide and collagen functional groups in the SBR composite. In addition, the thermal analysis revealed those collagen-filled composites had stable heat tolerance behavior, which is suitably used in extreme weather conditions. Moreover, the SBR/GO/1.5COL sample exhibited good characteristics in both mechanical and biodegradable properties. Thus, the product of SBR/GO/1.5COL could be regarded as a promising composite for green tires in the auto industry in the future.

Facial synthesis of highly active polymer vanadium molybdate nanocomposite: Improved thermoelectric and antimicrobial studies

Nanostructured Materials and their Potential as Electrochemical Sensors

Environmental pollutants are considered as the main concern for human life because it can affect health, especially via water sources. An enormous effort is needed to detect and monitor such contaminants from natural waters. Nanotechnology field offered combined benefits in regards to sensitive detection of environmental contaminants from water. This review describes the main types of water contaminants and recent approaches used for effective electrochemical detection of environmental pollutants with the aid of nanostructured materials.

Exploration of (S)-4,5,6,7-tetrahydrobenzo[d]thiazole-2,6-diamine as feasible corrosion inhibitor for mild steel in acidic media

Metal–Organic Framework (MOF) Compounds: Photocatalysts for Redox Reactions and Solar Fuel Production

Metal-organic frameworks (MOFs) are crystalline porous materials formed from bi- or multipodal organic linkers and transition-metal nodes. Some MOFs have high structural stability, combined with large flexibility in design and post-synthetic modification. MOFs can be photoresponsive through light absorption by the organic linker or the metal oxide nodes. Photoexcitation of the light absorbing units in MOFs often generates a ligand-to-metal charge-separation state that can result in photocatalytic activity. In this Review we discuss the advantages and uniqueness that MOFs offer in photocatalysis. We present the best practices to determine photocatalytic activity in MOFs and for the deposition of co-catalysts. In particular we give examples showing the photocatalytic activity of MOFs in H2 evolution, CO2 reduction, photooxygenation, and photoreduction.

How Accurately Can We Predict the Melting Points of Drug-like Compounds?

This article contributes a highly accurate model for predicting the melting points (MPs) of medicinal chemistry compounds. The model was developed using the largest published data set, comprising more than 47k compounds. The distributions of MPs in drug-like and drug lead sets showed that >90% of molecules melt within [50,250]°C. The final model calculated an RMSE of less than 33 °C for molecules from this temperature interval, which is the most important for medicinal chemistry users. This performance was achieved using a consensus model that performed calculations to a significantly higher accuracy than the individual models. We found that compounds with reactive and unstable groups were overrepresented among outlying compounds. These compounds could decompose during storage or measurement, thus introducing experimental errors. While filtering the data by removing outliers generally increased the accuracy of individual models, it did not significantly affect the results of the consensus models. Three analyzed distance to models did not allow us to flag molecules, which had MP values fell outside the applicability domain of the model. We believe that this negative result and the public availability of data from this article will encourage future studies to develop better approaches to define the applicability domain of models. The final model, MP data, and identified reactive groups are available online at http://ochem.eu/article/55638.

(2E)-3-(3,5-Dimethyl-1-phenyl-1H-pyrazol-4-yl)-1-(2,5-dimethyl-3-furanyl)prop-2-en-1-one

The title compound, (2E)-3-(3,5-dimethyl-1-phenyl-1H-pyrazol-4-yl)-1-(2,5-dimethyl-3-furanyl)prop-2-en-1-one (3) was synthesized in high yield by an aldol condensation between 3-acetyl-2,5-dimethylfuran and 3,5-dimethyl-1-phenylpyrazole-4-carboxaldehyde in ethanolic NaOH at room temperature. Its structure was fully characterized by elemental analysis, IR, 1H NMR, 13C NMR and EI-MS spectral analysis.

Ethyl (<i>Z</i>)-2-chloro-2-(2-phenylhydrazin-1-ylidene)acetate

The title compound, C(10)H(11)ClN(2)O(2), features an almost planar C(ar)-N(H)-N=C(Cl) unit [torsion angle = 0.8 (1)° whose phenyl substituent is almost coplanar with it [dihedral angle = 2.8 (2)°]; this unit is slightly twisted with respect to the carboxyl -CO(2) fragment [dihedral angle = 10.3 (2)°]. In the crystal, the amino group acts as a hydrogen-bond donor to the carbonyl O atom of an adjacent mol-ecule; the hydrogen bond generates a helical chain that runs along the b axis of the monoclinic unit cell.

2,6-Bis(9-ethyl-9H-carbazolylmethylene)cyclohexanone

The title compound, 2,6-bis(ethyl-9-ethyl-9H-carbazolylmethylene)cyclohexanone has been synthesized by condensation of 9-ethylcarbazole-3-aldehyde and cyclohexanone in ethanol in the presence of pyridine. The structure of this new compound was confirmed by elemental analysis, IR, 1H NMR, 13C NMR and EI-MS spectral analysis.

Synthesis, Characterization, Physicochemical and Electrochemical Studies of Novel Donor Acceptor Chromophores

Three donor acceptor chromophores were synthesized by Knoevenagel condensation. Structures of the chromophoes were conformed by the elemental analysis and EI-MS, FT-IR, 1H-NMR, 13C-NMR spectroscopy. Absorbance and fluorescence spectra of the chromophores were studied in different solvent provide that all the chromophores are good absorbent and emission. All chromophores give same behavior red shift in absorbance and emission spectra as polarity of the solvents increase. Photophysical properties including, oscillator strength, extinction coefficient, transition dipole moment and stokes shift were investigated in order to investigate the physicochemical behaviors of synthesized chromophores. The HOMO energy levels of compound 1, 2 and 3 respectively were calculated front the onset oxidation potential of cyclic voltammogram in acetonitrile.

Clouding phenomenon of amphiphilic drug promazine hydrochloride solutions: Influence of pharmaceutical excipients

Interaction of cationic amphiphilic drug nortriptyline hydrochloride with TX-100 in aqueous and urea solutions and the studies of physicochemical parameters of the mixed micelles

1-[(<i>Z</i>)-1-Ferrocenylethylidene]thiocarbonohydrazide

In the title compound, [Fe(C5H5)(C8H11N4S)], the cyclo-penta-dienyl (Cp) rings of the ferrocene unit are close to being eclipsed. They are inclined to one another at an angle of 1.95 (2)° and lie 3.309 (2)Å away from each other. The ethyl-idene-thio-carbonohydrazide fragment is planar, with an r.m.s. deviation of 0.0347 (2) Å from the mean plane of its eight non-H atoms, and makes dihedral angles of 21.78 (1) and 19.97 (1)° with respect to the two Cp rings. The mol-ecule adopts a trans geometry about the C=N double bond. In the crystal, N-H⋯(N/S) and C-H⋯S inter-actions stack the mol-ecules in an inverse fashion along the b axis.

Detection of bisphenol A based on conducting binder supported hydrophobic 1,10-PhenanNTf2 ionic liquid onto flat silver electrode by electrochemical approaches

The synthesis of room-temperature stable ionic liquids was obtained via metathesis reaction, which was accomplished by the reaction 1,10-Phenanthroline monohydrate hydrochloride with lithium-bis(trifluoromethane)sulfonamide in water (shortly, 1,10-PhenanNTf2). The prepared 1,10-PhenanNTf2 was characterized in details with various conventional methods. Finally, it was mixed with conducting binders and deposited on flat-silver electrode (AgE) to result in a sensor that has a fast response to bisphenol A (BPA) in the phosphate buffer phase (PBP). Features include high sensitivity, low-sample volume, reliability, reproducibility, ease of integration, long-term stability, and enhanced electrochemical responses. The calibration plot is linear (r2 = 0.9789) over the 0.1 nM–0.1 mM BPA concentration range. The sensitivity is ∼1.485 μA μM cm−2, and the detection limit is 0.09 ± 0.01 nM (at a signal-to-noise-ratio, SNR of 3). We believe that the developed approach significantly opens up a simple, fast, highly sensitive, and environment-friendly path to fabricate ionic liquid based chemical sensors with broad application prospects.

Superior removal of methylene blue using green fabricated pomegranate peel/nano-hematite composite: reusability, isotherm and kinetics study

Green hematite nanoparticles were synthesized using pomegranate peel extract of different concentrations (2 g, 4 g, and 6 g) and in the presence of the peel residuals. The obtained products defined as PP/GNH (I), PP/GNH (II), and PP/GNH (III) referring to the hematite nanoparticles at different concentrations compositing with pomegranate peel residuals. The products were addressed as green adsorbents for methylene blue dye contaminants in water. They exhibit superior adsorption properties with theoretical q_max of 666, 1111, and 909 mg/g for PP/GNH (I), PP/GNH (II), and PP/GNH (III), respectively. The equilibration times were attained after 480 min for the three products. The isotherm and kinetic studies indicate that the adsorption systems for the synthetic materials are of chemisorption type. The adsorption behaviors of these systems can be demonstrated according to Pseudo-second order as well as Elovich kinetic model. Furthermore, the adsorption results reflected a mono-layer uptake form which was more suitable for the Langmuir model than other investigated models. The products also showed high performances when it comes to remove the dyes investigated such as methylene blue Congo red, safranin, methyl orange, and crystal violet. Finally, green fabricated nano hematite/pomegranate peel composites are of high stability and can be reused for five cycles.Communicated by Ramaswamy H. Sarma.