Nahed A. Abd El-Ghany

A novel carboxymethyl xanthan gum‐based glycidyl methacrylate copolymer (CMXG‐g‐PGMA) was successfully synthesized using the graft copolymerization technique. During the grafting process, the epoxide ring of GMA was opened by the carboxylic groups of the CMXG, inducing crosslinking of their chains. The percentages of graft, graft efficiency, and homopolymer were 260%, 85%, and 35%, respectively. Two different concentrations of multiwalled carbon nanotubes (CNTs) were impregnated into the copolymer to obtain CMXG‐g‐PGMA/CNTs‐3% and CMXG‐g‐PGMA/CNTs‐5% composites. The topography, chemical, and inner structure of CMXG‐g‐PGMA and its CNTs composites were investigated employing FTIR, XRD, SEM, TEM, and BET. DPPH scavenging activity of CMXG‐g‐PGMA/CNTs‐5% is higher than that of CMXG‐g‐PGMA, since their IC ₅₀ values were 57.88 and 201.8 μg/mL, respectively. The CMXG‐g‐PGMA/CNTs‐5% has better inhibition performance against the HepG‐2 cancer cells growth than CMXG‐g‐PGMA, since their IC ₅₀ values were 52.1 and 269.8 μg/mL, respectively. CMXG‐g‐PGMA/CNTs‐5% showed better anti‐inflammatory activity than CMXG‐g‐PGMA with IC ₅₀ values of 10.9 and 217.8 μg/mL, respectively. CMXG‐g‐PGMA/CNTs‐5% exhibited good biocompatibility, showing no cytotoxic effects on normal human lung fibroblast cells at concentrations below 62.5 μg/mL. Thus, the incorporation of both GMA and CNTs into CMXG appreciably reinforced its antioxidant, anticancer, and anti‐inflammatory features. This represents a good way to achieve adequate formulations to contend with the classical medications employed for such implementations.

In the current study, pyromellitimide benzoyl thiourea cross-linked chitosan (PIBTU-CS) hydrogel, was evaluated as a green biocatalyst for the efficient synthesis of novel thiazole derivatives. The PIBTU-CS hydrogel showcased key advantages, such as an expanded surface area and superior thermal stability, establishing it as a potent eco-friendly catalyst. By employing PIBTU-CS alongside ultrasonic irradiation, we successfully synthesized a series of novel thiazoles through the reaction of 2-(4-((2-carbamothioylhydrazineylidene)methyl)phenoxy)-N-(4-chlorophenyl)acetamide with a variety of hydrazonoyl halides (6a–f) and α-haloketones (8a–c or 10a,b). A comparative analysis with TEA revealed that PIBTU-CS hydrogel consistently delivered significantly higher yields. This synthetic strategy provided several benefits, including mild reaction conditions, reduced reaction times, and consistently high yields. The robustness of PIBTU-CS was further underscored by its ability to be reused multiple times without a substantial reduction in catalytic efficiency. The structures of the synthesized thiazole derivatives were meticulously characterized using a range of analytical techniques, including IR, ¹H-NMR, ¹³C-NMR, and mass spectrometry (MS), confirming their successful formation. These results underscore the potential of PIBTU-CS hydrogel as a sustainable and recyclable catalyst for the synthesis of heterocyclic compounds. Additionally, all synthesized products were tested for their anticancer activity against HepG2-1 cells, with several new compounds exhibiting good anticancer effects.

The catalytic activity of chitosan (Cs) and grafted Cs led to the preparation of terephthalohydrazide Cs Schiff's base hydrogel (TCsSB), which was then investigated as an eco-friendly biocatalyst for synthesizing novel thiazole derivatives. TCsSB exhibited greater surface area and higher thermal stability compared to Cs, making it a promising eco-friendly biocatalyst. We synthesized two novel series of thiazoles via the reaction of 2-(2-oxo-1,2-diphenylethylidene) hydrazine-1-carbothioamide with various hydrazonoyl chlorides and 2-bromo-1-arylethan-1-ones, employing ultrasonic irradiation and using TCsSB as a catalyst. A comparative study between Cs and TCsSB revealed higher yields than TCsSB. The methodology offered advantages such as mild reaction conditions, quick reaction times, and high yields. TCsSB could be reused multiple times without a significant loss of potency. The chemical structures of the newly synthesized compounds were verified through IR, ¹H NMR, ¹³C NMR, and MS analyses. Six synthesized compounds were assessed for their in vitro antibacterial effectiveness by establishing the minimum inhibitory concentration against four distinct bacterial strains. The docking analyses revealed favorable binding scores against several amino acids within the selected protein (PDB Code-1MBT) for these compounds, with compound 4c exhibiting particularly noteworthy binding properties. Additionally, the in silico ADME parameter estimation for all compounds indicated favorable pharmacological properties for these compounds.

The microbial resistance to the traditional antibiotics causes serious health problems and increases day by day. Thus, there is a pressing need to discover alternative antimicrobial agents of different nature than that of the conventional antibiotics. For this, novel hydrogel nanocomposite films are prepared by chemical crosslinking grafting of carboxymethyl cellulose with N,N′‐methylene‐bis‐acrylamide (CMC‐g‐MBA), which subsequently followed by loading two different weight ratios of titanium oxide nanoparticles (TiO₂NPs), such as 3% (CMC‐g‐MBA/TiO₂NPs‐3%) and 5% (CMC‐g‐MBA/TiO₂NPs‐5%) wt%. Their chemical structure and surface morphology are confirmed using appropriate analytical techniques. Their antimicrobial activity can be arranged as follows: CMC‐g‐MBA/TiO₂NPs‐5% composite > CMC‐g‐MBA/TiO₂NPs‐3% composite > CMC‐g‐MBA hydrogel. While, the native CMC has no observable antimicrobial effect. CMC‐g‐MBA/TiO₂NPs‐3% composite imparts good barrier properties to the coated tomato fruits, delaying their spoilage and protecting them from the environmental microbes compared to the uncoated ones. CMC‐g‐MBA/TiO₂NPs‐5% composite is safe on the normal human cells. Thus, incorporation of both MBA and TiO₂NPs into CMC greatly develops its antimicrobial activity and provides a wonderful approach to attain promising materials that can efficiently compete with conventional antibiotics.

Terephthalohydrazide chitosan hydrogel (TCs) was prepared and investigated as an ecofriendly biopolymeric catalyst for synthesis of some novel thiazole and thiadiazole derivatives. Thus, TCs was used as a promising ecofriendly basic biocatalyst for preparation of three new series of thiazoles and two thiadiazoles derivatives via reacting 2-(2-oxo-1,2-diphenylethylidene) hydrazine-1-carbothio-amide with various hydrazonoyl chlorides and α-haloketones under mild ultrasonic irradiation. Also, their yield% was estimated using chitosan and TCs in a comparative study. The procedure being employed has the advantages of mild reaction conditions, quick reaction durations, and high reaction yields. It also benefits from the catalyst’s capacity to be reused several times without significantly losing potency. The chemical structures of the newly prepared compounds were confirmed by IR, MS, and ¹H-NMR. Docking analyses of the synthesized compounds’ binding modes revealed promising binding scores against the various amino acids of the selected protein (PDB Code—1JIJ). SwissADME’s online tool is then used to analyze the physiochemical and pharmacokinetic characteristics of the most significant substances. The majority of novel compounds showed zero violation from Lipinski’s rule (Ro5).