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The redox imbalance, caused by depletion or generation of reactive oxygen species (ROS), is a key mechanism by which metal complexes exert anticancer effects. Carbidopa has shown the ability to inhibit the MDA-MB-231 cell line, a highly aggressive triple-negative human breast adenocarcinoma, by inducing reductive stress. The metal complex of carbidopa with zinc (ZnCarbi) was designed to modify carbidopa's structure and exhibited increased cytotoxicity against MDA-MB-231 cells. Interestingly, ZnCarbi selectively targets certain cancer cells, showing no impact on the viability of normal HEK293 (human embryonic kidney) cells or other cancer cell lines like A549 (human lung adenocarcinoma), LM3 (murine breast adenocarcinoma), or HCT116 (human colon cancer). Treatment with carbidopa and ZnCarbi induces reductive stress, decreases ROS levels, increases the GSH/GSSG ratio, and protects cells from H₂O₂-induced death. Both compounds also cause mitochondrial damage, leading to cell death, and exhibit antimetastatic effects by inhibiting cell migration and invasion of MDA-MB-231 cells. Interaction studies with bovine serum albumin showed moderate binding through hydrophobic association. Overall, ZnCarbi demonstrates enhanced anticancer properties compared to carbidopa alone, highlighting its potential as an anticancer and antimetastatic compound.

The palladium-catalyzed aminocarbonylation is one of the most effective methods for the synthesis of carboxamides having great importance. Replacing fossil-based organic solvents in this routinely used catalytic protocol with biomass-derived media is crucial for developing environmentally safe alternatives and towards sustainability considerations. In this study, the open-chain derivatives of bio-originated substance γ-valerolactone i. e. alkyl 4-alkoxyvalerates (alkyl: methyl, ethyl, and propyl) were characterized and tested as potential polar aprotic alternatives of fossil-based common N,N-dimethylformamide (DMF) in aminocarbonylation protocols. First, the temperature-dependent physicochemical properties of alkyl 4-alkoxyvalerates were determined. Based on their characteristics, methyl 4-methoxyvalerate (Me-4MeOV) was selected and introduced in the Pd-catalyzed aminocarbonylation of iodobenzene and morpholine as a model reaction, and an optimization study was carried out. Using the optimized conditions, several substituted iodobenzenes, as well as heteroaryl iodides, were successfully applied resulting in the target carboxamides selectively in short reaction time. Furthermore, the aminocarbonylation of iodobenzene in the presence of various amines was also accomplished extending the scope of the carboxamides produced in this alternative medium. Considering our observations, such as high conversions (up to 95 %) in short reaction time and selective amide formation, it has been justified that Me-4MeOV could be an appropriate alternative medium in aminocarbonylation protocols.

Metal-Organic Frameworks (MOFs) are an emerging class of solid-state materials comprising inorganic elements and organic molecules. These hybrid materials are widely recognized for their diverse properties, rendering them indispensable in the field of organic synthesis, material science and the pharmaceutical industry. Although the traditional batch methods for MOFs synthesis are well-developed, they often struggle with reproducibility, scalability and environmental issues. However, the development of continuous flow techniques has emerged as a promising alternative, offering more efficient mass and heat transfer, precise reaction control, greater potential for automation, improved safety, and reduced environmental impact. This review primarily focuses on advanced continuous flow synthesis of MOFs incorporating techniques such as air flow, spray drying, microwave, micro-droplets, supercritical carbon dioxide, and ultrasound. Additionally, the recent advancements in applying MOFs as heterogeneous catalysts for various organic transformations under continuous flow conditions are discussed, categorized by the type of bond formation, including C-H bond formation (hydrogen reduction), C-C bond formation, and C-O bond formation.

In Singapore's hot and humid climate, watercolor papers are particularly prone to a paper oxidation issue known as foxing, which refers to the discoloration forming yellowish-brown stains on paper, changing the visual outcome of the watercolor artworks. This research investigates two most popular types of watercolor paper, made from 100 % cotton and cotton-wood-pulp mixture. Foxing was generally categorized into two types: biotic and abiotic foxing caused by fungi activities and the presence of metallic contaminants catalytic fungi growth. However, recent hypotheses further relate it to heterogeneous cellulose structures. Watercolor paper is typically produced in a well-controlled environment, which should theoretically reduce the occurrence of foxing, catalyzed by metallic contaminants. The research involved a comprehensive analysis of aged samples, from old watercolors, dating back to the 1990s and fresh watercolor paper samples. focusing on understanding the origin and causes of watercolor paper foxing based on cellulose content & structures. By comparing 100 % cotton and cotton wood-pulp blended watercolor paper, the susceptivity of foxing was hinted to be related to cellulose packing density. These findings will support further research in developing strategies for the conservation and storage of watercolor artworks.

The cover feature shows the structure of ammeline in the center, surrounded by its hydrogen bond palette, which gives rise to all the most stable possibilities of dimerization. In the background are two solvents that can affect the self-recognition of this supramolecular building block: water and chloroform. More information can be found in the Research Article by Andre Nicolai Petelski, Silvana Carina Pamies, and Nélida María Peruchena (DOI: 10.1002/cplu.202400436).

The front cover image showcases the first dinuclear trivalent lanthanide complexes with bis(mesitoyl)phosphide ligands, one of which is illuminated. The molecules are grown as yellow plate-shaped crystals, stored in a treasure chest. The rock has engraved magnetic susceptibility data featured through red and blue clams. The swimming fish are releasing bubbles that correspond to the traces of the UV-Vis spectra. The ocean scenery also shows orange spheres symbolizing the lanthanide ions. More information can be found in the Research Article by Selvan Demir, Saroshan Deshapriya, and Francis Delano IV (DOI: 10.1002/cplu.202400311).

The rapid growth of graphite market is highly coupled with the increasing demand for Li-ion grade graphite, the production of which results in significant losses of the graphitic material in the form of graphite fines. Herein, for the first time, we report an effective strategy to utilize industrial waste graphite fines through the development of graphene oxide-based nanohybrids as non-toxic and efficient antibacterial agents. To achieve this, graphene oxide (GO) was initially synthesized using industrial waste graphite fines as a graphitic precursor. Subsequently, hyperbranched polyethyleneimine (PEI), or either of its guanidinylated (GPEI) and N-sulfopropylated (SPEI) derivatives were successfully and homogenously attached onto GO, as confirmed by various characterization techniques, yielding GO-PEI, and novel GO-GPEI and GO-SPEI nanohybrids. The antibacterial activity of these nanohybrids was assessed against Gram (-) Escherichia coli and Gram (+) Staphylococcus Aureus bacteria. Both GO-GPEI and GO-SPEI were found to exhibit higher antibacterial activity, specifically against E. coli bacteria, compared to the pristine GO and GO-PEI nanohybrid, with GO-SPEI being more active than GO-GPEI. Finally, GO-GPEI and GO-SPEI were found to exhibit low cytotoxicity against mammalian cells, signifying that they can be used as potential antibacterial agents in various applications, including those in the disinfection industry.

The existing synthetic protocols for the direct functionalization of carbon-based nanomaterials often entail limitations due to their harsh reaction conditions, which require the use of high temperatures for extended periods. This study aims to overcome these limitations by developing mild and efficient synthetic protocols around 1,3-dipolar cycloaddition. Beginning with the well-established azomethine ylide derivatization, we progress to the utilization of nitrile oxide, and of nitrone derivatives for the functionalization of reduced graphene oxide (rGO) as well as of nanodiamonds (NDs). This comparative work employs both classical heating and microwave activation with the aim of reducing reaction times and enhancing efficacy. Results demonstrate that nitrone can react at 60 °C and that the reaction temperature may be decreased to 30 °C with nitrile oxide. Excellent progress was made in reducing the large excess of dipoles typically required for derivatization. Nitrile oxide was proved to be the most efficient in terms of derivatization degree, while nitrone was the most versatile reagent, facilitating the decoration of the carbon nanolayer with disubstituted dihydroisoxazole. To accurately assess the degree of functionalization, the reaction products underwent characterization using various spectroscopic and analytical techniques. Additionally, an indirect evaluation of the reaction outcome was conducted through Fmoc deprotection and quantification.

The critical micelle concentration is an important property of supramolecular detergents. Two dynamic light scattering approaches have been developed for critical micelle concentration analysis, i. e., concentration-dependent light scattering intensity analysis and diffusion coefficient analysis. Their utility as complementary tools for a reproducible determination of critical micelle concentration remains to be clarified. Herein, we address the question which of the two approaches is more suitable for obtaining reproducible critical micelle concentration values. We systematically compare both approaches in context with common detergent classes and benchmark utility by means of literature values. Our results show that the diffusion coefficient analysis delivers reproducible critical micelle concentration values in aqueous solutions. Our findings outline a roadmap to guide the critical micelle concentration analysis of detergents by dynamic light scattering in the future.

Alginate biopolymer is widely employed in many industrial fields thanks to its pleasing features of biodegradability, biocompatibility, low toxicity, and relatively low cost. The gelling process of alginate with divalent cations is fairly simple and thus it is used as a versatile biomaterial to tailor the desired mechanical and moisture properties. This study focused on developing new gel formulations to enhance the properties of calcium-alginate hydrogel (CA). The newly synthesized hydrogels, referred to as CA-CHEM gels, were chemically cross-linked with different ratios of pentaerythritol tris[3-(1-aziridinyl)propionate] (PTAP) through the reaction between the carboxylic groups of alginate and aziridines of PTAP. The reaction was successfully monitored by NMR. The new CA-CHEM gels were chemically characterized using FTIR-ATR, while SEM analysis confirmed the changes in the porosity and homogeneity of the network. Additionally, thermogravimetric analyses and mechanical properties showed improvement in degradation stability and in structural strength, compared to plain CA, with an increasing PTAP content up to 1 % w/w. Finally, the new CA-CHEM gels effectively controlled water absorption and release. In particular, CA-CHEM-1 performed as the most controlled system, making it promising for delivering aqueous cleaning solutions on water-sensitive surfaces such as a wooden historical musical instrument.