ChemistryOpen最新文献

Alcohols are common alkylating agents and starting materials alternative to harmful alkyl halides. In this study, a simple, benign and efficient pathway was developed to synthesize 1,3-diphenylpropan-1-ols via the β-alkylation of 1-phenylethanol with benzyl alcohols. Unlike conventional borrowing hydrogen processes in which alcohols were activated by transition-metal catalyzed dehydrogenation, in this work, t-BuONa was suggested to be a dual-role reagent, namely, both base and radical initiator, for the radical coupling of aromatic alcohols. The cross-coupling reaction readily proceeded under transition metal-free conditions and an inert atmosphere, affording 1,3-diphenylpropan-1-ol with an excellent yield. A good functional group tolerance in benzyl alcohols was observed, leading to the production of various phenyl-substituted propan-1-ol derivatives in moderate-to-good yields. The mechanistic studies proposed that the reaction could involve the formation of reactive radical anions by base-mediated deprotonation and single electron transfer.

A Pro-Gly-typed cyclopeptide, cyclosenegalin A, was firstly isolated from Annona senegalensis and Annona scleroderma. In this study, we reported synthesis the cycloheptapeptide with a combination of solid- and solution-phase synthetic methods. This study also compared the effectiveness of β-turn inducer type I and II in cyclosenegalin A to facilitate the cyclization process. The synthesis of cyclosenegalin A were prepared using two different sequences of linear peptides for cyclization. First sequence employed β-turn type I inducer (Ser-Ala-Val-Thr) as turning point and second sequence employed β-turn type II inducer (Thr-Pro-Gly-Leu). The successful cyclization was obtained using the linear sequence of NH₂-Ala-Val-Thr-Pro-Gly-Leu-Ser-OH with β-turn type II. The final product was obtained in 8.2 % yield with PyBOP/DIEA act as coupling agent. The synthetic cyclosenegalin A were characterized with HR-ToFMS, ¹H NMR, ¹³C NMR, HSQC, HMBC, TOCSY, and ROESY. The synthetic product was also evaluated for its antimicrobial activity.

Interdigital electrodes were prepared using nanoimprint lithography and piezoelectric inkjet printing. These processes are simpler and more cost-effective than the industrially used electron beam lithography because of their purely mechanical process step. For the investigation of material dependence, platinum as well as carbon electrodes were fabricated. Afterwards electrodes with various line widths and spacings were tested for the application as a chemiresistive sensor for ferrocenyl-methanol and the influence of the gap-width and conductor cross-section on the sensitivity was investigated. The general suitability of the systems for the production of such structures could be confirmed. Structures with a limit of detection (LOD) down to 1.2 μM and 35.9 μM could be produced for carbon and platinum, respectively, as well as a response time of 3.6 s was achieved.

The front cover illustrates the direct electrochemical regeneration of 1,4-NADH under varying operating conditions—steady-state and dynamic—at a porous carbon-based electrode′s surface. Dynamic operation accelerates 1,4-NADH regeneration, demonstrating potential for integration with an enzymatic reaction that converts cyclohexenone to cyclohexanone using an enoate reductase. More details can be found in the Research Article by Tanja Vidaković-Koch and co-workers (DOI: 10.1002/open.202400064).

The present study describes an eco-friendly NBS-assisted regioselective synthesis of new 5-acylfunctionalized 5-acylfunctionalized 2-(1H-pyrazol-1-yl)thiazoles by condensation of 3,5-dimethyl-1H-pyrazole-1-carbothioamide with unsymmetrical 1,3-diketones under solvent-free conditions. The structural elucidation of the newly synthesized compounds was accomplished using various spectroscopic techniques viz. FTIR, NMR and mass spectrometry. All the newly synthesized compounds were examined for their in vitro antimicrobial potential against both pathogenic gram positive and gram negative bacterial and fungal species as well as anthelmintic activity against Pheretima posthuma earthworms. The results of antimicrobial activity revealed that all tested compounds 3 a–j showed excellent antimicrobial potential particularly against S. aureus. It was also observed that compounds 3 e and 3 i (MIC=62.5 μg/mL) showed greater potency against E. coli, whereas compounds 3 a and 3 h (MIC=50 μg/mL and 62.5 μg/mL) demonstrated better activity against P. aeruginosa and compound 3 i (MIC=62.5 μg/mL) exhibited superior activity against S. pyogenus when compared to standard drug Ampicillin (MIC=100μg/mL). Compound 3 e and 3 j revealed remarkable antifungal and anthelmintic activities. To find out binding interactions of target compounds with target proteins and pharmacokinetic parameters of the compounds, in silico investigations involving molecular docking studies and ADMET predictions were also performed.

The emergence of drug-resistant viruses and novel strains necessitates the rapid development of novel antiviral therapies. This need was particularly demanding during the COVID-19 pandemic. While de novo drug development is a time-consuming process, repurposing existing approved medications offers a more expedient approach. In our prior in silico screening of the DrugBank database, fidaxomicin emerged as a potential SARS-CoV-2 papain-like protease inhibitor. This study extends those findings by investigating fidaxomicin‘s antiviral properties in vitro. Our results support further exploration of fidaxomicin as a therapeutic candidate against SARS-CoV-2, given its promising in vitro antiviral activity and favorable safety profile.

This article focuses on comparing the characteristics of cotton fabric dyed with Diospyros mollis extract (DME) solution and that of cotton fabric dyed with the reactive dye. The parameters of the cotton fabric after dyeing with both types of dyes were assessed, including color strength (K/S), structural morphology, infrared spectrum, antibacterial properties, UV resistance, color fastness to washing, rubbing, light, moisture absorption, breathability, and wastewater indices. The obtained results show that the K/S value of cotton fabric dyed with DME solution is slightly lower than that of cotton fabric dyed with the reactive dye, 18.52 and 19.36, respectively. The cotton fabric dyed with the reactive dye does not exhibit antibacterial activity against Escherichia coli and Staphylococcus aureus, whereas the antibacterial effectiveness against these bacteria for cotton fabric dyed with DME solution is 99.99 %. The UV protection capability of cotton fabric dyed with DME solution is superior to cotton fabric dyed with the reactive dye. The BOD/COD ratio of wastewater from the dyeing process with DME is higher than that of the reactive dye, with values of 0.70 and 0.32, respectively. The findings of this study indicate the superior ability of using DME solution as compared to the reactive dye, which is promising as a natural dye for fabric in medical applications.

This study presents the synthesis of TiO₂-graphene nanocomposites with varying mass ratios of graphene (2.5, 5, 10, 20 wt. %) using a facile and cost-effective hydrothermal approach. By integrating TiO₂ nanoparticles with graphene, a nanomaterial characterized by a two-dimensional structure, unique electrical conductivity and high specific surface area, the resulting hybrid material shows promise for application in supercapacitors. The nanocomposite specimens were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Raman microscopy, field-emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). Additionally, supercapacitive properties were investigated using a three-electrode setup by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) tests. Notably, the TiO₂-20 wt. % rGO nanocomposite exhibited the highest specific capacitance of 624 F/g at 2 A/g, showcasing superior electrochemical performance. This specimen indicated a high rate capability and cyclic stability (93 % retention after 2000 cycles). Its remarkable energy density and power density of this sample designate it as a strong contender for practical supercapacitor applications.

In this work we have derived the parameters of an AMOEBA-like polarizable forcefield for electrolytes based on tetramethoxy and tetraethoxy-glyoxal acetals, and propylene carbonate. The resulting forcefield has been validated using both ab-initio data and the experimental properties of the fluids. Using molecular dynamics simulations, we have investigated the structural features and the solvation properties of both the neat liquids and of the corresponding 1 M LiTFSI electrolytes at the molecular level. We present a detailed analysis of the Li ion solvation shells, of their structure and highlight the different behavior of the solvents in terms of their molecular structure and coordinating features.

A selective direct arylation of the different Csp2-H bonds of imidazo[2,1-b]thiazole with (hetero) aryl halides can be achieved simply by switching from a palladium catalyst system to the use of stoichiometric amounts of copper. The observed selectivity, also rationalized by DFT calculations, can be explained by a change in the mechanistic pathways between electrophilic palladation and base-promoted C−H metalation.