Journal of Saudi Chemical Society最新文献

A series of six novel polyesters (P₁-P₆) were obtained via by direct polycondenzation with hydroxyl functional-appended chromone and curcumin based monomers (M₁, M₂ and M₃) were synthesized and subjected to thermogravimetric and spectroscopic analyses for structural characterization. The synthesized polymers were soluble common organic solvent such as DMF, THF, DMAc and 1-methyl-2-pyrrolidinone (NMP). The molecular weight of the polymers was found to be ranged from 3.390 × 10⁵ – 1.1 × 10⁵ g/mol by GPC-MALS. X-ray diffraction pattern of polyesters indicates P₁, P₂ and P₃ are amorphous in nature, whereas polymer P₄, P₅, and P₆ shows crystalline nature. The receptor VEGFR2 kinase can expand the synthesized molecules into 2D and 3D supramolecular networking through π-π stacking, hydrophobic, and H-bonding interactions. The cell viability effects of polymers on the growth of cell lines A549, HeLa and VERO were evaluated in vitro by MTT assay. The polymer P₃ displayed potent anticancer activity compared to the other polymers. Research is undergone in developing curcumin chromone functional polymer as a workable biopolymer which could find value in the present findings.

The present study was designed to improve the aqueous solubility and dissolution rate of citreorosein, a poorly water soluble drug, by producing its nanoparticles (NPs) using an “antisolvent precipitation with a syringe pump” (APSP) method. Various process parameters including flow rate, stirring speed, temperature, drug concentration and solvent-antisolvent ratio were investigated and optimized to obtain the smallest particle size of citreorosein. The prepared NPs were subjected to different analytical techniques such as SEM, FTIR, XRD and DLS. The NPs were tested for different dissolution parameters including difference (f₁) and similarity factors (f₂), dissolution efficiency (DE) and mean dissolution time (MDT). The antioxidant potential of citreorosein and its NPs were evaluated using DPPH, ABTS, and FRAP models, while their cytotoxicity was tested on various cancer cell lines such as breast (MDA-MB-231), lung (A549) and liver (HepG2), using the MTT assay. The specificity of the test compound was investigated against two normal human primary epithelial cells including renal (HRPTEpiC) and alveolar (HPAEpiC) cells. DLS analysis revealed that the prepared NPs were less than 200 nm in size while SEM and XRD confirmed their rod shape and amorphous nature, respectively. Citreorosein-NPs exhibited enhanced solubility and dissolution rate in all medias as compared to pure citreorosein. The NPs displayed significant antioxidant effects against ABTS, DPPH and FRAP models, with IC₅₀ values of22.6, 21.45 and 27.30 µg/ml, respectively. Moreover, it showed significant cytotoxic activity against MDA-MB-231, A549 and HepG2 cells, with IC₅₀ values of 3.45, 4.5 and 6.23 µg/ml, respectively. Furthermore, the NPs demonstrated high selectivity index values for the aforementioned cell lines as compared to reference drugs. This study demonstrated that APSP method successfully produced citreorosein-NPs and hence, showed better aqueous solubility, dissolution rate, antioxidant and cytotoxic activities than the pure compound.

Water pollution caused by textile dyes is considered a major and growing issue. To address this challenge, in this research, water-stable Cu-MOFs/GO composite catalysts were produced using the hydrothermal synthesis method as an efficient persulfate (PDS) activator for methyl orange (MO) degradation. We also explored the changes in surface morphology, crystal structure, surface functional groups, and valence states of the materials before and after the introduction of GO by Cu-MOFs. It was shown that Cu-MOFs/GO demonstrates a more stable surface structure, and the unique folded structure of GO provides a better hydrophobic environment for Cu metal cluster hence making MOF easier to grow. The Cu-MOFs/GO-PDS system showed a high activation performance on persulfate in a wide pH range (3–11), meanwhile, was less affected by the presence of natural anions in the environment and more inhibited by natural organic matter citric acid. Furthermore, the Cu-MOFs/GO had excellent stability, reusability and structural integrity, and the removal rate of MO was maintained after five cycles. In terms of oxidation mechanism, in addition to the generation of ·SO4⁻ and OH· radicals, there were also singlet oxygen ¹O₂ and active Cu(III) in the system, and all of these active substances contributed to the removal of pollutant MO.

In this study, a novel copolymer hydrogel according to poly (acrylonitrile-co-sodium styrene sulfonate) (ASD) as an effective adsorbent was prepared via free radical polymerization of the solution at a ratio of 1:1 to remove cationic crystal violet dye (CV) from wastewater. The prepared hydrogel was thoroughly characterized using FTIR, TGA, SEM and EDX analysis. The hydrogel that was produced has a notable capacity for adsorbing cationic dye uptake over a wide pH range as well as easily separated without the need for filtration and centrifugation. Under optimal conditions using 1 g/L of hydrogel, 400 mg/L dye concentration and contact time of 5 h, the prepared hydrogel showed high dye removal efficiency approaching 100 %. The sulfonated copolymer hydrogel has a maximum adsorption capacity of 518.49 mg/g, which is six times larger than pristine PAN. The Langmuir model properly represented the isotherm adsorption data, however the kinetics data was better described by the pseudo-second-order model. Based on the calculated thermodynamic characteristics, the process of CV dye adsorption on sulfonated copolymer hydrogel surface was spontaneous and exothermic.

Fluopyram is a highly effective agricultural fungicide targeting succinate dehydrogenase (SDH). Twenty-six novel amide derivatives containing azetidine were designed and synthesized with fluopyram as the lead, and their biological activities were tested. The results showed that some compounds had obvious antifungal activities against Phomopsis sp., among them, the EC₅₀ value of compound C24 was 5.7 mg/L, which was significantly better than fluopyram (105.4 mg/L). The curative and protective activities of compound C24 on kiwi fruit infected with Phomopsis sp. were 42.2 and 52.9 %, which were better than that of fluopyram (30.4 and 35.6 %) at 200 mg/L. Moreover, compound C24 exhibited excellent inhibitory against SDH. The results of scanning electron microscopy (SEM) indicated that the mycelium of Phomopsis sp. collapsed or even ruptured after compound C24 treatment. Meanwhile, molecular docking showed that compound C24 was deeply embedded into the SDH binding pocket, and the binding model was stabilized by a cation–π interaction with Cys-40, Tyr-58 and an H-bond with Lys-455 and Asn-452. Compound C24 can provide a valuable idea to find new succinate dehydrogenase inhibitors.

The present study describes an environmentally benign biological method for the production of zinc oxide nanoparticles (ZnO NPs) by blending water-based leaf extract from a sustainable bio-source, the Arjuna tree, under ambient conditions. Aqueous leaf extract comprised of different reducing agents appeared as the precursor for phytofabrication, and zinc nitrate hexahydrate (ZnNO₃·6H₂O) acted as a zinc source. The phytofabricated Arjuna-ZnO NPs had a hexagonal shape with an average size of 31.14 nm, as revealed by HR-TEM, FE-SEM micrographs, and XRD patterns. The FESEM-EDS micrograph and the XRD patterns also revealed the elemental composition, phase purity, and crystalline nature of phytofabricated Arjuna-ZnO NPs. The initial formation of ZnO NPs was confirmed by absorption maxima at approximately 376 nm and Zn-O stretching vibrations at 520 cm⁻¹ using UV–VIS and an FT-IR spectrophotometers, respectively. The aqueous extract of Arjuna leaf was also analysed using FT-IR spectrophotometer to identify the functional groups of bioactive substances that participated in the reduction and encapsulation processes. The efficacy of the Arjuna-ZnO NPs was assessed in terms of their ability to photocatalyzed on three noxious dyes, methylene blue (MB), methyl orange (MO), and congo red (CR), for high commercial and industrial usage. The phytofabricated Arjuna-ZnO NPs were photoactive and proved highly efficient and effective nano-photocatalysts for the photodegradation of three dyes, MB, MO, and CR, under natural sunshine, underscoring their potential for effective remediation of environmental pollutants. The degradation process adhered to pseudo-first-order kinetics in terms of adsorption kinetics.

There is a growing demand for decreasing fossil fuel usage. That being said, we should move toward renewable and sustainable energy sources. Iron-based catalysts are usually employed in this route. In this work, an incipient impregnation process was used for preparing four γ-Al₂O₃ supported iron-based catalysts with different weight percents including 20Fe/5Cu/γ-Al₂O₃, 20Fe/5Cu/2K/γ-Al₂O₃, 20Fe/5Cu/3Zr/γ-Al₂O₃ and 20Fe/5Cu/1.5Zr/1K/γ-Al₂O₃ under the pressure of 20 atm, the temperature of 285 °C, H₂ to CO ratio of one, and a gas hourly space velocity of 2 NL/ (h. gCat). BET, FE-SEM, XRD, H₂-TPR, ICP, and TEM techniques were used to determine the characteristics of the catalysts, while gas chromatography results were used to determine CO conversion and product selectivity. Due to the synergistic effect of the two promoters, the doubly-promoted catalyst exhibited a C₅⁺ selectivity of 64.2 %, surpassing both the Fe/Cu/γ-Al₂O₃ catalyst and the singly-promoted catalysts. This result highlights the enhanced performance of the doubly-promoted catalyst. Compared to the other catalysts prepared, the doubly-promoted catalyst demonstrated a higher carbon monoxide (CO) conversion rate of 67.7 % and yield of 43.5 %. Moreover, The results demonstrate the significant impact of Zr and K promoters of the synthesized Fe-based catalysts on hydrocarbon product distribution.

Carbon nanotubes (CNTs) are highly promising materials for the adsorption of dyes from water. Recently, there has been a growing interest in Prussian blue-type coordination polymers due to their inexpensive nature, chemical stability, and simple synthesis using non-toxic metals that are prevalent in the earth. The results present a straightforward technique for effectively altering the surface of CNT using cobalt-iron-based prussian blue (CoFe-PB). The procedure led to a significant increase in the removal of crystal violet (CV) from water relative to the bare CNTs. The maximum removal efficiency (about 93 %) of CV dye was obtained at pH 6 with fast saturation time (15 min). The use of the coating approach yields a core–shell structure consisting of CNT as the core and a CoFe-PB shell. The CoFe-PB shell, with a thickness of 10–15 nm, forms a highly conformal coating that completely covers the CNT. The high conformance of the coating is considered an essential characteristic for its strong adsorption performance. The method demonstrates the significant potential of prussian blue-type materials, when appropriately coated, as very effective adsorbent materials.

Two silver alkynyl clusters, [(CO₃²⁻)@Ag₂₀(^tBuC≡C)₁₄(PhCOO)₃(CF₃COO)] (1) and [(CO₃²⁻)@Ag₂₀(^tBuC≡C)₁₄(PhCOO)(CF₃COO)₃] (2), composed of alkynyl Ag₂₀ shell templated by a CO₃²⁻ anion and supported by carboxyl ligands PhCOO⁻ and CF₃COO⁻, were synthesized successfully by conventional methods. Single crystal X–ray diffractometer (SCXRD) was used to determine the precise structures of 1 and 2. Although compounds 1 and 2 have the [(CO₃²⁻)@Ag₂₀(^tBuC≡C)₁₄]⁴⁺ unit, the numbers of PhCOO⁻ and CF₃COO⁻ ligands along with Ag···Ag interactions were affected by the steric hindrance of different carboxyl ligands and their concentrations. That is, compounds 1 and 2 separately contain the [(CO₃²⁻)@Ag₂₀(^tBuC≡C)₁₄(PhCOO)(CF₃COO)]²⁺ unit, which is involved in the ligand exchange between PhCOO⁻ and CF₃COO⁻. Powder X-ray diffraction (PXRD), fourier transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA) were used to characterized compounds 1 and 2. The photocurrent responses, absorption spectra, as well as luminescence of 1 and 2 have been studied. In addition, the reduction of H₂O₂ for GCE–1 and GCE–2 showed good electrocatalytic activity, and catalysts 1 and 2 showed good photocatalytic degradation efficiency of methylene blue (MB). The results suggest that 1 and 2 can act as new electrocatalysts and photocatalysts to detect and decompose organic pollutants and hazardous materials in wastewater.

The photocatalyzed cleavage of cycloketoximes is a promising approach for modifying their biological activity and designing prodrugs activated by light. Cycloketoximes containing a cyclic ring structure that can hinder their degradation and modification in biological systems. Photocatalysis offers a sustainable and efficient method for breaking down the cyclic structure using a photocatalyst and exposure to ultraviolet light. These reactions are initiated by iminyl radicals, that gain access to distal-carbon through selective C–C cleavage. This process provides a solution for the challenging task of modifying the biological activities of cycloketoximes. Moreover, it can also be useful for selectively removing protecting groups from organic molecules or cleaving specific chemical bonds, thereby facilitating organic synthesis.This review article covers synthetic uses of photocatalyzed cleavage of cycloketoximes and highlights its ongoing research in the field of photocatalysis.