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A feasible alternative to classic chemical synthesis, the phyto-mediated production of silver nanoparticles (AgNPs) utilizing aqueous flower petal extract of Cassia alata as a reducing agent is reported for the first time. Characterization of synthesized AgNPs was carried out using various techniques viz., ultraviolet-visible spectroscopy (UV-Vis), X-ray powder diffraction (XRD), high-resolution transmission electron microscope (HRTEM), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX). The results of the FTIR research conducted in this study show different bond stretches with varying durations, which can be seen at various faraway points. AgNPs are mainly spherical and vary in size from 20 to 100 nm, according to TEM images. The highest X-ray energy surge, at 3 keV, is visible in the EDX spectrum. The XRD pattern showed that four diffraction peaks could be assigned to the 111, 200, 220, and 311 planes of the face-centered cubic crystalline silver, respectively, at 32.05, 46.27, 55.25, and 57.39°. Optimization of production parameters including pH, metal ion concentration, and substrate concentrations were studied. In addition, the bioactivity was evaluated against Trichophyton rubrum, Aspergillus fumigatus, Candida albicans, Epidermophyton floccosum, and Mucor sp. using the agar diffusion method. Furthermore, their antioxidant properties were assessed using 2,2-diphenyl-1-picryl-hydrazyl-hydrate assay and ferric ion reducing antioxidant power tests. MTT assay was performed using human fibroblast cell line (L929) to determine the cell viability and cytotoxicity through increased metabolism of the tetrazolium salt.

B3LYP/cc-pVDZ generated the best N-(5-((4-ethylpiperazin-1-yl)methyl)pyridin-2-yl)-5-fluoro-4-(4-fluoro-1-isopropyl-2-methyl-1H-benzo[d] imidazol-6-yl) pyrimidin-2-amine (TA) results. The NBO study shows that the LP (1) N16 to π*(C17-N19) has the highest stabilization energy at 53.86 kcal/mol. Electron localization and delocalization areas are confirmed by wavefunction studies. The Gaussian-16w software establishes thermodynamic properties for a titled compound which is confirmed by various solvents. The frontier molecular orbital studies we confirmed by gas phase have the highest bond gap value which is 4.02 eV. The titled compound nitrogen is the nucleophilic attack (blue color) and oxygen is the electrophilic attack (red color), which is confirmed by MEP study. In non-linear optical (NLO) study water solvent shows the highest dipole moment activity, due to the solvent's interaction the gas phase dipole moment is lower. The docking study showed the greatest binding affinity score of −5.28 kcal/mol. [ABSTRACT FROM AUTHOR]

A new class of (N‐(pyrimidin‐2‐yl)‐4‐((1,7,7‐trimethylbicyclo [2.2.1] heptan‐2‐ylidene) amino) benzenesulfonamide (CDA) was synthesized from commercially available camphor and sulfadiazine. The synthesized Schiff‐base was characterized by FT‐IR, 1H and 13C NMR spectroscopic analyses. The HOMO, LUMO, MEP, chemical reactivity parameters, and NBO were calculated using the WB97XD/cc‐pVDZ basis set. For better understanding, the electronic absorption and emission of the compound were recorded using UV‐Vis and fluorescence spectra. Molecular docking simulations were investigated between ligand (compound) and target protein. The computational results correlate well with observed values. The frontier molecular orbital energy gap (3.78 eV) revealed that the studied molecule has higher polarizability and chemical reactivity with lower kinetic stability. In addition, compound showed the highest binding score −5.72 kcal/mol, which was confirmed by a molecular docking simulation. [ABSTRACT FROM AUTHOR]

An efficient palladium‐catalyzed annulation of 3‐arylquinazolinones with mono and double alkyne insertion was developed for the synthesis of fused quinazolinone derivatives in 43–80 % yields. A notable effect was observed in product yield, when bases/additives were modulated. The reaction mechanism is believed to proceed through C−X cleavage/alkyne insertion/1,4‐Pd migration and C−H annulation in a one‐pot manner. [ABSTRACT FROM AUTHOR]

Excessive emission of CO2 has caused a critical greenhouse effect that is emerging as a major threat to the environment. Electrocatalytic reduction of CO2 is an advanced technology where chemically inert CO2 is reduced and can be used to produce value-added fuels or chemicals. In this work, the electrocatalytic performance of a single Cu atom embedded in a MoS2 monolayer with a sulfur vacancy for the electroreduction of CO2 is studied using density functional theory (DFT) with dispersion correction. The single Cu atom is stably located in the sulfur vacancy of the MoS2 monolayer. The multiple pathways explored here involve proton–electron pair transfer in the CO2 reduction reaction (CO2RR) to yield a variety of C1 products, such as HCOOH, CO, CH3OH and CH4. These pathways were examined using the corresponding free energy profiles and overpotentials. Among the different C1 products, CH4 formation is more favored via the following optimized pathway: *CO2 → *OCHO → *OCHOH → *OCH2OH → *OCH2 → *OCH3 → *OHCH3 → *OH + CH4 → H2O. The MoS2 monolayer with embedded Cu has enhanced CO2RR activity with an appreciably low overpotential compared to pristine MoS2. This study provides a deep understanding of the structure–reaction relationships and various mechanistic pathways of the CO2RR, and could aid in the design of high-performance single-atom electrocatalysts. [ABSTRACT FROM AUTHOR]

A variety of alpha-aroylacetones 4a-g is prepared in excellent yields following a new protocol wherein alpha-ami-nonitriles alpha-aminonitriles as the aryl acyl anion equivalents readily react with propargyl bromide as the alpha-bromoacetone equivalent. The alkylated product undergoes one-pot unmasking of the keto functionality along with Markovnikov's hydration of the terminal alkyne with CuSo4.5H2O in aqueous methanol at 60 degree Celsius to furnish the desired target in excellent isolated yields.