RSC Advances最新文献

In this work, we present a straightforward synthetic route for the preparation of functionalized β-meso-fused porphyrins, which are subsequently connected to rylendiimides. The resulting donor–acceptor-type conjugates exhibit intriguing optical properties, such as panchromatism and profoundly bathochromically shifted absorption curves. A better understanding of the molecules' electronic structure was gained through density-functional theory calculations, which unveiled small HOMO–LUMO gaps.

Correction for ‘Cancer treatment approaches within the frame of hyperthermia, drug delivery systems, and biosensors: concepts and future potentials’ by Zeinab S. Sayed et al., RSC Adv., 2024, 14, 39297–39324, https://doi.org/10.1039/D4RA06992G.

The development of synthetic methodologies that promote greener reactions have become so essential that it has slowly shaped the way chemists think about the construction of physiologically and chemically active compounds. The acid-catalyzed iminoketone – aldehyde condensations leading to Hydroxy imidazole N-oxides serve as robust strategies for forming C–N bonds. Considering all the existing challenges that come with the use of solvent and energy-intensive methodologies, herein a green synthetic strategy using ultrasound with optimization of reaction conditions and thorough investigation into the mechanism for obtaining the best yields are reported. Additionally, the importance of the Hydroxy Imidazole N-oxides synthesis is highlighted by their in vitro antiproliferative activity study. Though only satisfactory, the results are promising. It gives us scope for building upon this simple scaffold with appropriate functionalization, which may lead to furhter enhancement in their anti-proliferative activity.

Domino Knoevenagel-cyclization reactions of styrene substrates, containing an N-(ortho-formyl)aryl subunit, were carried out with N-substituted 2-cyanoacetamides to prepare tetrahydro-4H-pyrano[3,4-c]quinolone and hexahydrobenzo[j]phenanthridine derivatives by competing IMHDA and IMSDA cyclization, respectively. The diastereoselective IMHDA step with α,β-unsaturated amide, thioamide, ester and ketone subunits as a heterodiene produced condensed chiral tetrahydropyran or thiopyran derivatives, which in the case of Meldrum's acid were reacted further with amine nucleophiles in a multistep domino sequence. In order to simplify the benzene-condensed tricyclic core of the targets and get access to hexahydro-1H-pyrano[3,4-c]pyridine derivatives, a truncated substrate was reacted with cyclic and acyclic active methylene reagents in diastereoselective Knoevenagel-IMHDA reactions to prepare novel condensed heterocyclic scaffolds. The chemo-, regio- and diastereoselectivity of the cyclization step were investigated and structural elucidation was aided by single crystal X-ray analysis.

Bone defects represent a significant challenge in clinical practice, driving the need for innovative solutions that effectively support bone regeneration. Barrier membranes, due to playing a critical role in creating an environment conducive to bone regeneration by preventing the infiltration of non-osteogenic tissues, are widely applied to bone repair. However, inadequate spatial stability and osteogenesis-promoting ability often limit current barrier membranes. In response to these challenges, we have developed an advanced gelatin methacrylate/hydroxyapatite/hydroxyapatite membrane (GelMA/HAp/HAM) composite biomaterial designed as a barrier membrane with superior spatial stability and optimal degradation properties. The GelMA/HAp/HAM composite features a bilayer structure, with each layer possessing distinct properties: the dense hydroxyapatite membrane (HAM) acts as a barrier to prevent connective tissue infiltration. In contrast, the porous gelatin methacrylate/hydroxyapatite (GelMA/HAp) hydrogel layer promotes osteogenesis. Studies have demonstrated the composite's excellent biocompatibility and its significant osteogenic differentiation enhancement. This composite membrane holds great promise for clinical applications in bone defect repair, providing a new avenue for improving patient outcomes in regenerative medicine.

Saline-tolerant medicinal plants possess novel chemical constituents with high bioactivity because of their unique secondary metabolic pathways. Limonium sinense, an aquatic plant found in the coastal wetlands of the Yellow River Delta, was collected and studied in the present work. Ten drimane-type sesquiterpenoids and four triterpenoids, including six new ones (sinenseines A–F), were isolated from a whole plant of L. sinense for the first time. Their structures, including the absolute configurations, were determined by analyzing the comprehensive spectroscopic data. In addition, twelve terpenoids, including nine sesquiterpenoids, were identified using UPLC-MS/MS and GNPS methods. All isolates were evaluated for their antiproliferative and anti-inflammatory activities. Compounds 2–4, 6, 13, and 14 showed moderate anti-tumor effects on A549, H1299, HepG2 and A2780 cells with IC₅₀ values ranging from 35.2 ± 2.0 to 90.5 ± 3.1 μM. Furthermore, compound 1 exhibited significant anti-inflammatory activity with an IC₅₀ value of 8.3 ± 1.2 μM against NO production in LPS-induced RAW 264.7 macrophages.

Crafting highly dispersed active metal sites on catalysts is an optimal method for improving the catalytic reactivity and stability, as it would improve atomic utilization efficiency, enhance reactant adsorption and activation ability through unique geometric and electronic properties. In this study, two synthesis methods were employed (ammonia evaporation (AE) and the impregnation method (IM)) to load Rh species onto the ZSM-5 support in order to attain tunable dispersivity, during which a 1.25-fold increase in the total yield of liquid oxygenated products (32 433.33 μmol g_cat⁻¹ h⁻¹) was achieved specifically over a Rh–ZSM-5-AE sample when the reaction was carried out at a loading level of 0.3 wt% and at 240 °C for half an hour. The results of the study revealed that this elevated productivity originated from the smaller size and higher degree of dispersion of Rh clusters on AE samples. It was demonstrated that the ammonia evaporation method would cause Si leaching and introduce a substantial number of –OH groups during the preparation process, which worked in coordination in altering the electronic structure of Rh species. Consequently, these modifications modified the disordered Rh precursor adsorption, which resulted in a more homogeneous distribution of Rh species, hence facilitating the activation of methane. This study offers a practical and constructive approach for improving the dispersion of Rh nanoclusters and designing strong metal–support interactions (SMSI).

The focus on energy efficiency to move towards a more sustainable use of resources has intensified efforts to minimize friction and wear in mechanical systems, which account for 23% of the world's energy consumption. In this study, polyoxometalate ionic liquids (POM-ILs) are introduced as environmentally acceptable lubricant additives, for their potential friction-reducing and anti-wear (AW) properties. These compounds, characterized by their complex structures and tunable properties, have been investigated for their tribological performance across base fluids of varying polarities. Their performance has been compared against zinc dialkyldithiophosphate (ZDDP), a standard AW additive. Our findings demonstrate that POM-ILs exhibit promising friction-reducing and AW capabilities, comparable to traditional additives. The efficacy of POM-ILs was found to be highly dependent on the base fluid used, with significant variations observed in their ability to interact with stainless steel surfaces. Adsorption studies confirmed strong adsorption of POM-ILs onto stainless steel, with notable influence from the base fluid. Advanced characterization techniques revealed the formation of a predominantly oxide-rich tribofilm on the metal surface, as a result of POM-IL decomposition and reaction with the metal. POM-ILs show significant potential as lubricant additives, with their structural versatility offering a promising path for future greener developments in tribology.

During the initial cycling of lithium-ion batteries, the generation of SEI at the electrode–electrolyte interface and the occurrence of irreversible side reactions consume the active lithium, resulting in irreversible loss of volume (ICL), which may also be accompanied by electrode volume changes and structural collapse. Addressing these challenges has become critical, and pre-lithiation with additional lithium has emerged as a key way to improve battery performance. Hence, this review comprehensively analyzes and summarizes the causes of ICL in lithium-ion batteries, and systematically discusses various prelithiation methods and mechanisms of different electrode structures, especially electrodes. Moreover, we discuss the importance of developing effective electrolyte, separator, and binder pre-lithiation technologies to improve ionic conductivity and battery life. The effectiveness of each strategy in improving initial capacity and cycling stability, while addressing compatibility issues and minimizing potential side effects, is evaluated to inform the future development and large-scale application of pre-lithiation technology.

In recent research, quinoline and indole structures have gained recognition for their significant clinical relevance and effectiveness. These compounds are known for their wide-ranging pharmacological effects, which include anticancer, antibacterial, antifungal, antiviral, and anti-inflammatory properties. Researchers have successfully implemented a variety of innovative synthetic strategies, leading to the creation of numerous compounds that display fascinating biological activities in diverse fields. This has sparked growing interest in developing quinoline and indole-based analogues, given their impressive variety of biological effects. Over the past few years, new, efficient, and more accessible synthetic techniques—such as green chemistry and microwave-assisted synthesis—have been introduced to produce a diverse array of quinoline and indole structures. This development reflects an expanding area of interest in both academic and industrial settings, making it easier to investigate their biological capabilities. In this review, we examine the intriguing transformations of 2-alkynyl aryl and benzyl azide derivatives into indoles and quinolines, emphasizing the role of metal catalysts such as Au, Cu, Rh, Pd, and Ag, from 2011 to 2024. We showcase the variety of substrates involved, highlight notable advancements in this area of research, and address the limitations faced by chemists. Additionally, we offer insights into the mechanisms driving these important reactions, aiming to enhance understanding and inspire future work in this dynamic field.