Publications

Based on reported results for the potential medicinal impact of phenothiazine core, as well as the chalcone skeleton that is widely present in many natural products, together with their reported bioactivities, the present work was aimed at combining both moieties in one molecular skeleton and to synthesize and characterize a novel series of chalone-based phenothiazine derivatives. For this purpose, 2-acetylphenothiazine was N-alkylated, followed by the Claisen-Schmidt reaction to produce the chalcones with good yield. Antioxidant activity, as evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, was assessed to determine if their antioxidant potential was comparable with ascorbic acid, and attributable to the phenothiazine core. Screening anticancer activities of the synthesized chalone-based phenothiazine derivatives against human breast cancer cell line MCF-7 cells, and human hepatocellular carcinoma HepG-2 cells, compared with standard drugs cisplatin and doxorubicin, was evaluated. The results revealed that compounds 4a<b>,</b> 4b<b>,</b> 4d<b>,</b> 4h<b>,</b> 4j<b>,</b> 4k<b>,</b> 4m<b>,</b> 4o<b>,</b> and 4p were good against human hepatocellular carcinoma HepG-2 cells, and among these compounds 4b and 4k were the most effective compounds, with IC₅₀ values of 7.14 μg/mL and 7.6 1 μg/mL, respectively. On the other hand, compounds 4a<b>,</b> 4b<b>,</b> 4k<b>,</b> and 4m were good against human breast cancer cell line MCF-7 cells and, among these compounds, 4k and 4b were the most effective compounds, with IC₅₀ values of 12 μg/mL and 13. 8 μg/mL, respectively. The overall results suggest that these compounds could, potentially, be further modified for the formation of more potent antioxidant and anticancer agents.

AbstractThe linear and nonlinear optical (NLO) properties of methoxybenzylidene (1) and thiophen-2-ylmethylidene (2) tetrahydronaphthalone derivatives are studied using long-range corrected density functional theory (LC-DFT). The calculated hyperpolarisabilities indicate that both compounds have measurable NLO properties (approximately one to two times the hyperpolarisability of p-nitroaniline). Charge-transfer indices and time-dependent DFT calculations suggest that the NLO properties are a result of a charge-transfer excitation, which is typical in conjugated donor–acceptor structures. The ultraviolet–visible spectra of 1 and 2 are also predicted using gap-fitting schemes, and these data are used to assess how accurately the hyperpolarisabilities of 1 and 2 could be estimated by the solvatochromic method.Keywords: nonlinear opticsorganic materialsDFTrange-separated hybridssolvatochromic method AcknowledgementsThe authors acknowledge the technical and financial support of King Abdulaziz University.Additional informationFundingThis work was funded by King Abdulaziz University [grant number 21-3-1432/HiCi].

The development of green hydrogen generation technologies is increasingly crucial to meeting the growing energy demand for sustainable and environmentally acceptable resources. Many obstacles in the advancement of electrodes prevented water electrolysis, long thought to be an eco-friendly method of producing hydrogen gas with no carbon emissions, from coming to fruition. Because of their great electrical conductivity, maximum supporting capacity, ease of modification in valence states, durability in hard environments, and high redox characteristics, transition metal oxides (TMOs) have recently captured a lot of interest as potential cathodes and anodes. Electrochemical water splitting is the subject of this investigation, namely the role of transition metal oxides as both active and supportive sites. It has suggested various approaches for the logical development of electrode materials based on TMOs. These include adjusting the electronic state, altering the surface structure to control its resistance to air and water, improving the flow of energy and matter, and ensuring the stability of the electrocatalyst in challenging conditions. In this comprehensive review, it has been covered the latest findings in electrocatalysis of the Oxygen Evolution Reaction (OER) and Hydrogen Evaluation Reaction (HER), as well as some of the specific difficulties, opportunities, and current research prospects in this field.

&nbsp; This research evaluated the physicochemical equivalence of some samples of Nifedipine 20 mg Retard Tablets available in Nigeria. Seven samples were randomly procured from various zones of the country and standard protocols applied to evaluate their tablet weight uniformity, dimensions, hardness, disintegration time, content of active Ingredient and&nbsp;in vitro&nbsp;drug release profile. Results showed that all the samples tested were chemically, but not physically equivalent. Although within each sample, compendial requirement for tablet weight uniformity was met, there were significant differences in the mean tablet weights, diameters and thickness of the samples studied (p &lt; 0.05). Furthermore, tablet hardness and disintegration time varied much among the samples, but not within each sample. All the samples met the compendial requirement for content of active ingredient and released more than 80% of the drug within 4 h. It is therefore pertinent that manufacturers of this product be advised to formulate tablets that are equivalent in size, as different tablet sizes may impart negative psychological effects on clinicians and their patients when the need arises for switch over from one product to another, since the availability of particular products is never guaranteed at all times in Nigeria, a largely import dependent nation. &nbsp; Key words:&nbsp;Nifedipine 20 mg Retard tablets, physicochemical equivalence,&nbsp;in-vitrodrug release.

Abstract Nanostructured ternary/mixed transition metal oxides have attracted considerable attentions because of their high‐capacity and high‐rate capability in the electrochemical energy storage applications, but facile large‐scale fabrication with desired nanostructures still remains a great challenge. To overcome this, a facile synthesis of porous NiCoO 2 nanofibers composed of interconnected nanoparticles via an electrospinning–annealing strategy is reported herein. When examined as anode materials for lithium‐ion batteries, the as‐prepared porous NiCoO 2 nanofibers demonstrate superior lithium storage properties, delivering a high discharge capacity of 945 mA h g −1 after 140 cycles at 100 mA g −1 and a high rate capacity of 523 mA h g −1 at 2000 mA g −1 . This excellent electrochemical performance could be ascribed to the novel hierarchical nanoparticle‐nanofiber assembly structure, which can not only buffer the volumetric changes upon lithiation/delithiation processes but also provide enlarged surface sites for lithium storage and facilitate the charge/electrolyte diffusion. Notably, a facile synthetic strategy for fabrication of ternary/mixed metal oxides with 1D nanostructures, which is promising for energy‐related applications, is provided.