An efficient natural-based catalyst constructed of volcanic pumice, cellulose polymeric chains, and palladium nanoparticles is presented for Suzuki–Miyaura coupling reaction.

Therapeutic nano-bioconjugates (TNBCs) as an advanced class of drug delivery systems have attracted much attention due to more efficacy than the individual medications. Hence, in this study, a novel anti-infection TNBC system is designed based on highly porous silica nanoparticles, gold nanoparticles (AuNPs), and hybridized polyvinyl alcohol (PVA) for the efficient delivery of cefixime (CFM). Furthermore, a conjugation of cysteine−arginine (CR) dipeptide is made onto the surfaces for the enhancement of cell adhesion. Concisely, the AuNPs incorporated inside the PVA network play the key role in the controlled release process triggered by localized surface plasmon resonance (LSPR) heating. The drug content of the CFM-containing cargo (named as CFM@SiO 2 /PVA/Au−CR) and related release profile have been precisely studied by the confirmed analytical methods. Eventually, confocal microscopy on the stained cells has revealed that the TNBC particles are capable of entering the Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) bacterial cells better than the individual CFM. Also, optical density experiments (OD 600 ) have corroborated that the prepared CFM@SiO 2 /PVA/Au−CR TNBC includes a high antimicrobial effect on K. pneumoniae and E. coli cells with (93.0 ± 1.5) % and (86.8 ± 1.0) % success rates, respectively, whereas the same dosage of the individual CFM has shown a lower effect on the cell growth rate. Also, estimation of minimum inhibitory/ bactericidal concentrations (MIC/MBC) confirmed the enhanced antibacterial property of the CFM through the presented delivery method. Overall, this product is suggested to be clinically administrated instead of the individual CFM due to its high efficacy and containing lower dosage of the antibiotic drug.

In this work, some new azotated 2H-chromene derivatives were successfully synthesized by use of mesoporous Cu-SBA-15 as nanocatalyst leading short reaction times and high yields. By this research, the scope of azo compounds was increased.

A series of novel azo group fused 2 H-chromenes and 4 H-chromenes were synthesised as well as pyranopyrazole derivatives via the Knoevenagel condensation reaction of C–H acid compounds with 5-(arylazo)salicylaldehydes by a nucleophilic addition to the carbonyl group followed cyclisation.

Two efficient synthetic routes to preparation of 2,3‐diarylimidazo[1,2‐a]pyrazines and 2,3‐diarylimidazo[1,2‐b]pyridazines are described. The procedures involve a Suzuki cross‐coupling reaction and a palladium‐catalyzed direct arylation at position 3 and finally a comparative study is achieved. The antibacterial activities of the synthesized compounds in vitro were measured and the results showed that most products presented moderate to good antibacterial activities. Compounds 3a, 3c, 3j, 3k, 3l, and 3n revealed obvious potency against Staphylococcus aureus, Bacillus subtilis, and Escherichia coli with minimum inhibitory concentration values of 32 μg/mL, which were better compared with the others.

A new metal‐free decarboxylative coupling reaction between coumarin‐3‐carboxylic acid derivatives, formaldehyde, and amines is developed. The use of water as the solvent without using any catalyst or additive, excellent functional group tolerance, and good yields are the beneficial features of this synthetic pathway. The cholinesterase inhibitory activity of some selected target compounds is also evaluated.

a b s t r a c tThe aim of this work was to apply iron oxide magnetic nanoparticles coated with 3-(trimethoxysilyl)-1-propanethiol, for adsorption of the cationic dye, methylene blue (MB), from aqueous solutions prior to determination with UV-Vis spectrophotometry. To approach this purpose, iron oxide magnetic nanoparticles (IOMNPs) were synthesized via co-precipitation method and characterized by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy. The effective parameters such as pH, time, adsorbent amount, type and volume of the desorption solvent, ionic strength of the solution and the sample volume were optimized. Figures of merit such as detection limit, relative standard deviation (RSD) and linearity range were calculated as 0.24 mg L -1 , 6.8% and 0.32-16 mg L -1 , respectively. Kinetic studies proved that adsorption process obeys pseudo-second-order model, also the adsorption isotherm was best fitted to Freundlich model with maximum adsorption capacity of 27.78 mg/g. Eventually, the method was successfully used for removing MB from a textile mill wastewater with recoveries ranging from 60% to 102%.

Aim and Objective: Herein, A series of new imidazo[1,2-a]pyridine-chalcone derivatives 3a-m were designed and synthesized to find new class of antibacterial agents. These compounds were prepared by the aldol condensation of 2-phenylimidazo[1,2-a]pyridine-3-carbaldehyde 2a-b with acetophenone derivatives and other aromatic acetyls. High reaction yields have been obtained in a short reaction time, through applying this multi-step pathway. Materials and Methods: In vitro antibacterial activities of the synthesized imidazo[1,2-a]pyridine-chalcones were measured against S. aureus, B. subtilis and E. coli with MIC values of 32 -128 μg/mL. Finally, essential structural analyses such as CHN and NMR spectroscopies were used to identify the synthesized chalcones based on imidazo[1,2-a]pyridine derivatives. Results: The results showed that most of the products presented moderate to good antibacterial activities. Compounds 3b, 3d, 3g, 3l and 3m revealed obvious potency against S. aureus, B. subtilis and E. coli with MIC values of 32 μg/mL and 64 μg/mL, which were better when compared with other chalcones. Conclusion: The synthesized antibacterial compounds were obtained with appealing advantages such as high purity, simple pathway, good to excellent yields, inexpensive and easy availability of materials as well as good activities against bacteria. So in this work, new class of antibacterial chalcones based on imidazo[1,2-a]pyridine have been reported.