2-Hydroxy-pyridines (or commonly named 2-pyridones) are widespread nitrogen heterocycles in natural and synthetic products and their applications in biological, pharmaceutical and agrochemical compounds are becoming increasingly important. Therefore, several procedures have been described in the literature for the preparation of this heterocyclic framework. Among them, multicomponent reactions are current in synthetic organic chemistry where reducing reaction times, high yields and ease of product isolation are the main benefits of this method.

In order to study the effect of the aforementioned method under greener medium, we herein describe a novel one-pot route for the design of 4,6-diaryl-3-cyano-2-pyridone derivatives under free solvent conditions. The three-component condensation of alkenes, ketones and ammonium acetate afforded efficiently the target heterocycles with higher yields in short time reaction comparing to a classical method.

Hydrophobic Deep Eutectic Solvents (HDESs) have found application in water purification in recent years. The extent of their stability in aqueous media determines whether they are suitable materials for water purification or they end up constituting greater pollution load to the water they are to purify. This work sought to prepare HDESs from a monoterpene (menthol), and three long chain organic acids (octanoic acid, decanoic acid, and dodecanoic acid). The physicochemical characteristics of the prepared HDESs were investigated. Thereafter, their moisture absorption capacity and stability in aqueous medium was determined to ascertain whether they are actually hydrophobic as predicted

Sustainable polymers derived from biomass have the potential to reduce environmental impact while offering significant performance and cost advantages over petrochemical-derived macromolecules. We present here a facile and efficient approach to the synthesis of a biomethacrylic monomer: isobornyl methacrylate (IBOMA) using the naturally available camphor terpene in the essential oil of the Algerian plant Artemisia arborescens (Absinthe) as a key intermediate. The essential oil of the aerial part of the Artemisia arborescens plant naturally distributed in northwest Algeria was isolated by hydrodistillation and analyzed using gas chromatography-mass spectrometry (GC/MS) techniques. Nine components were identified representing 90.7% of the total content. The main constituent of Artemisia arborescens essential oil is camphor (71.8%). Camphor was purified and modified to produce an 80% renewable carbon-based methacrylic monomer. This terpene-derived methacrylic monomer was free-radically polymerized to create a biosourced methacrylic polymer. Nuclear magnetic resonance (NMR) was used to characterize the structure of camphor terpene, isobornyl methacrylate and poly (isobornyl methacrylate) (PIBOMA).

Numerous organic and inorganic compounds, as well as transition metals, have been mentioned, as homogeneous catalyst, in chemical processes. However, the utilization of these homogeneous catalysts is inhibited by challenges such as separation of products from the reaction mixtures and the recycling of catalysts, despite their high catalytic activity resulting from the increased contact surface of the homogeneous catalysts with reactants. In recent years, various research have been accomplished on graphene oxide due to its remarkable chemical and mechanical properties. Among these applications, the use of modified graphene oxides as catalysts is of extreme importance. In this work, 1-amino-2-naphthol-4-sulfonic acid functionalized graphene oxide (GO-ANSA) was employed, as a new and highly effective heterogeneous nanocatalyst, for the preparation of tetraketone derivatives through multicomponent reaction of 1,3-diketones with aromatic aldehydes. This catalyst proceeds rapid conversion of substrates and affords high yields of the products. Furthermore, it is recyclable, easily separable and environmentally friendly.

The aim of this research was simple preparation of the modified chitosan by polyethylene glycol (Cs-PEG) through a green procedure. To achieve this goal, polyethylene glycol was grafted to the chitosan and making a hydrogel. In particular, chitosan, a natural polymer, stands out as a first-choice material for hydrogels elaboration in biomedical, cosmetic, and health related applications, owing to its interesting properties including biocompatibility, biodegradability, antimicrobial capacity, and mucoadhesivity. Moreover, chitosan also allows drugs to absorb easier through biological barriers. pH-Responsive nanoparticles are regarded as an ideal candidate for anticancer drug targets. The obtained nanomaterial was characterized by using different spectroscopic, microscopic and analytical methods. Various techniques and methods namely Fourier transform infrared (FTIR), field emission scanning electron microscopy (FESEM), ultraviolet-visible spectroscopy (UV-VIS) were utilized to identify the nanomaterial. Then, the doxorubicin (DOX) was loaded onto the Cs-PEG hydrogel, as a pH-responsive nanocarrier, for anticancer drug delivery. In conclusion, the efficiency of the drug load increases because of the hydrogel structure of the Cs-PEG and it can decrease the side effects of drugs including DOX.

The aim of this study is to synthesis of pyrrole derivatives based on phenacyl bromide and amine, which is promoted by a green and heterogeneous chitosan-based catalyst under optimal laboratory conditions through the multi-component reaction strategy namely Hantzsch pyrrole synthesis. This bio-based CS-EDTA-THEIC network contains appropriate basic and acidic active sites to act as a multifunctional catalyst. Indeed, the CS-EDTA-THEIC nanomaterial used in the multicomponent reaction for synthesis of pyrrole derivatives showed excellent yields in short reaction times. Furthermore, the CS-EDTA-THEIC network, as a heterogeneous catalyst, illustrated magnificent reusability and can be used at least six times without significant loss of its activity.

The aim of this research was simple preparation of grafted 1,3,5-Tris (2-hydroxyethyl isocyanurate) to the chitosan surface by using EDTA linker (CS-EDTA-THEIC) through a green and inexpensive procedure. The obtained nanomaterial was characterized via different spectroscopic, microscopic and analytical methods. Various techniques and methods namely Fourier transform infrared (FTIR), field emission scanning electron microscopy (FESEM), simultaneous thermogravimetric analysis (STA), X-ray diffraction analysis (XRD) were utilized to identify the nanomaterial. This bio-based CS-EDTA-THEIC network contains appropriate basic and acidic active sites to act as a multifunctional catalyst. Finally, the CS-EDTA-THEIC nanomaterial was used in the multicomponent reaction for synthesis of 4H-pyrans and showed excellent yields in short reaction times. Furthermore, the CS-EDTA-THEIC network, as a heterogeneous catalyst, illustrated magnificent reusability and can be used at least five times without significant loss of its activity.

The continuous need to develop novel antibacterial agents remains a challenging predicament facing the drug development industry due to the major problem of bacterial resistance. In this study, we report the identification of a new N-(5-nitrothiazol-2-yl)-3-oxopyrazolidine-4-carboxamide derivative (RW18) as a potent inhibitor of Clostridioides difficile. C. difficile is a gram-positive, anaerobic spore-forming bacterium that is listed by the CDC as an urgent threat. It is the leading cause of nosocomial diarrhea ranging from mild diarrhea to lethal colitis, spreading worldwide with the lack of many treatment alternatives. Altogether, C. difficile is ranked as an alarming concern to the health system. RW18 was discovered during our synthetic efforts to discover MurA inhibitors targeting cell wall synthesis in bacteria. RW18 exhibited significant MurA inhibition, with IC₅₀ value of 9.8 μM as well as demonstrated nearly the same inhibitory activity against MurA C115D, the mutant version developed by resistant E. coli towards fosfomycin. Notably, RW18 displayed potent activity against several Clostridioides difficile clinical isolates with MIC values ranging between 0.125 and 1 μg/mL. It was found to possess bactericidal activity with MBC values 0.25 -1 μg/mL. When tested against the normal intestinal microbiota, RW18 showed a significantly reduced inhibition. In addition, when tested against Caco-2 cells, RW18 showed a high safety index, indicating that it should not show harmful effects to the colon cells if administered orally. Finally, the compound was highly stable in LB culture medium as well as with bacterial cell lysate. Overall, RW18 presents a promising lead compound against Clostridioides difficile.

The evolution of Hydrophobic Deep Eutectic Solvents (HDESs) has expanded the applications of the new generation solvents known as Deep Eutectic Solvents (DES) to include water-based operations. How stable they are in aqueous media qualifies them to be categorized as hydrophobic. This will also determine whether they are appropriate materials for water-based industrial processes or not; or whether they end up constituting a greater pollution load to those processes due to the leaching of their precursors into the aqueous media when used. This work sought to prepare HDESs from a monoterpene (thymol), and three long-chain organic acids (octanoic acid, decanoic acid, and dodecanoic acid). The physicochemical characteristics of the prepared HDESs were investigated. Thereafter, their moisture absorption capacity and stability in aqueous environments

In recent years, various research have been accomplished on the catalytic applications of chitosan and its derivatives. In this research, methyl methacrylate grafted to chitosan (Cs-MMA) was employed as a new biopolymeric nanocatalyst for the synthesis of imidazole derivatives through multi-component reaction (MCR) strategy. Characterization of the obtained nanomaterial has been done via different spectroscopic, microscopic, and analytical methods such as Fourier transform infrared (FTIR), X-ray diffraction analysis (XRD), field emission scanning electron microscopy (FESEM). This nanocatalyst showed high yields of the products and short reaction times. This heterogeneous catalyst illustrated magnificent reusability and can be used at least six times without significant loss of its activity.