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.
Steroidal[oxazolo(4,5-b)quinoxaline-2-yl-hydrazone] derivative (7a–9a) (7b–9b) were prepared by the multi-step reactions of steroid. It is prepared via the reaction of steroidal semicarbazones with 2,3-dichloroquinoxaline at 80 °C in ethanol. The structures of the compounds were evident by IR, 1H NMR and mass spectrometry and their purities were confirmed by elemental analyses. The antibacterial activity of these compounds was evaluated by the disk diffusion assay against two Gram-positive and two Gram-negative bacteria and then the minimum inhibitory concentration (MIC) of compounds was determined. The results showed that compounds (7a, 7b, 8a, 8b) are better antibacterial agent as compared with the standard drug amoxicillin.
Purpose The purpose of this study is to prepare various CeO 2 -based carbon material (CNT, CB, GO) nanocomposites through a wet chemical process for the development of a sensor probe to detect various environmental toxins by using an electrochemical approach under room temperature conditions. A comparative study on sensitive and selective phenolic sensor (4-methoxyphenol; 4-MP) has been fabricated by modifying a glassy carbon electrode (GCE) with various nanocomposites (NCs) such as CeO 2 , CeO 2 –CNT (carbon nanotubes), CeO 2 –CB (carbon black) and CeO 2 –GO (graphene oxide) NCs. Design/methodology/approach The CeO 2 –CNT NCs were prepared by the wet chemical method at low temperature. NCs were characterized by various methods such as transmission electron microscopy (TEM), Fourier-transform infra-red (FTIR), ultra-violet/visible (UV-Vis) spectroscopy and XRD (X-ray diffraction). CeO 2 –CNT NCs were immobilized as a film on the flat surface of the GCE by using binders (5% Nafion). The electrochemical measurements of the 4-MP detection with the CeO 2 –CNT NCs/Nafion/GCE sensor were studied by the current-voltage method. Findings In the optimal conditions, the sensitivity, detection limit and limit of quantification of 4-MP sensor probe were found to be 47.56 µAcm-2 µM −1 , 12.0 ± 0.2 nM and 40.0 ± 0.5 nM (S/N of 3), respectively. Research limitations/implications This electrochemical sensor showed an acceptable analytical performance in the detection of 4-MP with higher sensitivity, lower detection limit, large dynamic concentration range, good reproducibility and fast response time. Practical implications This electrochemical approach can be applied practically for the determination of selective 4-MP in real environmental and extracted samples. Social implications CeO 2 –CNT NCs/Nafion/GCE sensor probe was used for the safety of environmental and health-care fields at larger scales. Originality/value This electrochemical approach is a significant achievement on the development of sensor probe. The results are indicated as being technically detailed with an up-to-date account of recent chemical sensor research studies.
The 15 non-H atoms of the title compound, C(11)H(12)N(2)O(2), are approximately coplanar, the r.m.s. deviation being 0.145 Å. The major deviation from coplanarity is seen in a twist between the ethene (E configuration) and pyrrole rings [C-C-N-C torsion angle = -8.26 (18)°]. The carbonyl O and cyano N atoms are syn to each other. In the crystal, supra-molecular linear tapes linked by C-H⋯O and C-H⋯N inter-actions are further connected by C-H⋯π(pyrrole) inter-actions.
Two new series of polyamides, 7 a-e and polyoxazoles 8 a-e , containing diphenyl ether segments were synthesized using a low-temperature solution of polycondensation and polycyclization reactions, respectively. Polyamides were synthesized by interaction of monomer 4 with different aliphatic and aromatic diacid chlorides, including adipoyl, sebacoyl, oxaloyl, 4,4′-azodibenzoyl and 3,3′-azodibenzoyl dichlorides. The poly-merization reaction was carried out in dry DMF as a solvent and in the presence of anhydrous potassium carbonate as a catalyst at room temperature. Polyoxazoles were obtained as cyclization products form corresponding polyamides in polyphosphoric acid. The model compounds 5 and 6 were synthesized to know the optimum polymerization procedures. The structure of the model compounds as well as the resulting polymers was characterized by elemental and spectral analyses. The synthesized polymers were soluble in protonic solvents such as formic and concentrated sulfuric giving different colors. The thermal properties of those polymers were evaluated by TGA, DTG, and DTA measurements and correlated to their structural units. FDT for polyamides was nearly complete at around 730–750°C, while for polyoxazoles it was nearly complete at around 580–650°C. The glass transition temperatures for the selected polymers were in the range of 47–74°C, while T m values were in the range of 156–315°C. X-ray analysis showed that the selected polyamides have a higher degree of crystallinity than polyoxazoles in the region 2θ = 5−60°. In addition, the morphological properties of selected examples were tested by SEM measurements. A comparative SEM study was carried out between selected polyamides and polyoxazoles.
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.
This study presents a sustainable, green synthesis of silver-coated magnetite nanocomposites (Ag-Fe3O4) using Brachychiton populneus leaf extract, aiming to develop an efficient and reusable photocatalyst for wastewater treatment. The nanocomposites combine the visible-light plasmonic activity of silver nanoparticles (AgNPs) with the magnetic recovery capability of Fe3O4, resulting in a multifunctional hybrid material. Comprehensive characterization using XRD, SEM, EDX, FTIR, UV–Vis spectroscopy, BET surface area analysis, and VSM confirmed successful formation of Ag-Fe3O4 with a mesoporous structure, uniform particle distribution, reduced bandgap (1.95 eV), and strong magnetic properties. The photocatalytic performance was evaluated by the degradation of methylene blue (MB) and Congo red (CR) under visible light. The composite demonstrated superior photocatalytic efficiency, achieving 97% and 92% degradation of MB and CR (20 ppm), respectively, within 30 min, significantly outperforming individual AgNPs and Fe3O4. Kinetic studies confirmed pseudo-first-order reaction behavior. The enhanced activity was attributed to the synergistic effect of Ag and Fe3O4, which improved light absorption, interfacial charge separation, and reactive oxygen species (ROS) generation. This work highlights the potential of green-synthesized Ag-Fe3O4 as a highly efficient, magnetically recoverable, and environmentally friendly photocatalyst for wastewater remediation applications.
