AbstractIn this work, the adsorption of Trypsin on synthesized Silver (Ag), Graphene Oxide: Silver (GO: Ag) nanocomposite (2:1), and Graphene Oxide (GO) nanoparticles (NPs) and, their effect on the conformation of Trypsin was studied by various spectroscopic and microscopic techniques to understand the transition of nano Protein Corona (PC) from “hard” to “soft.” The results showed that the adsorption of Trypsin on synthesized NPs followed the Freundlich adsorption isotherm and pseudo‐second‐order kinetics. The conformational changes that occurred in Trypsin upon interaction with synthesized NPs were investigated by using Circular Dichroism (CD), Fluorescence, and Fourier Transform Infrared (FTIR) spectroscopy. The morphological investigation of nano PC using High‐Resolution Transmission Electron Microscopy (HR‐TEM) and Atomic Force Microscopy (AFM) indicated the formation of hard, semi‐soft, and soft nano PC in the presence of Ag, GO: Ag, and GO NPs, respectively. The negative value of the thermodynamic parameters ΔG, ΔH, and ΔS in all three cases suggests the reaction to be exothermic and spontaneous. The van der Waals interaction and hydrogen bonding are the major forces responsible for binding Trypsin on the surface of Ag, GO: Ag, and GO. The catalytic efficiency of trypsin in the absence and presence of NPs was examined by performing the protein assay showing the highest catalytic activity of pure Trypsin compared with trypsin‐NPs constructs. Our findings provide useful information for the applications of GO‐based nanocomposites for various biological applications.

AbstractOrganic and medicinal chemists have shown great interest in developing simple approaches for creating linear triquinane structures, as they are crucial for synthesizing both natural and synthetic products. Linear triquinane shows various biological characteristics like being commonly used for antitumor, antibacterial, and antimalarial purposes, making it a popular subject of study among synthetic chemists. These come from different sources like marine organisms, plants, and fungi and make up a significant group of sesquiterpenoids. These can be classified as cis‐syn‐cis or cis‐anti‐cis based on the stereochemistry at the ring junction, with cis‐anti‐cis being the most common type and exhibiting significant biological activity. In this review, we summarized different methods using a combination of photothermal and olefin metathesis strategy to construct a triquinane framework by utilizing both traditional heat and microwave radiation. Some commonly used synthetic methods, including metathesis protocol and key reactions like Grignard reaction and Diels–Alder reaction, were utilized together with ring‐closing, ring‐opining, and ring‐rearrangement metathesis to create the linear triquinane core for use in total synthesis of natural products. Additionally, the use of photothermal olefin metathesis along with Hosomi‐Sakurai reaction conditions allows for the creation of intricate polyquinanes, which can be used to produce complex natural compounds and for designing unique molecules theoretically.

AbstractMagnetic ionic liquids (MILs) are a subclass of ionic liquids that exhibit paramagnetic properties intrinsically, without the need for additional magnetic particles. These properties can be attributed to the cations, anions, or both. Typically, MILs incorporate transition or inner‐transition metals within the anion structure. These adaptable liquids demonstrate remarkable physicochemical properties, notably a robust response to external magnetic fields. The body of research concerning the synthesis, characterization, and practical applications of MILs has expanded swiftly in recent times. This review delves into the latest research on the synthesis, properties, and utilization of MILs across various domains, including catalysis, fluid‐fluid separation, polymer science, and analytical chemistry. Within the realm of analytical chemistry, MILs are pivotal, serving as solvents in various analytical procedures such as dispersive liquid‐liquid micro‐extraction, matrix solid‐phase dispersion, and single‐drop micro‐extraction. Owing to their paramagnetic nature, MILs are instrumental in the separation process, streamlining organic reactions by obviating the need for traditional extraction or centrifugation steps.

AbstractThree N‐substituted benzimidazole cobalt(II) complexes have been synthesized and fully characterized by elemental analysis, FT‐IR spectroscopy, and X‐ray crystallography. The crystal packing formation features were studied by AIM analysis, and the energy and nature of both weak noncovalent interactions in the crystal and metal–ligand coordination bonds were assessed. These N‐coordinated cobalt(II) complexes were screened for antimicrobial activities against Gram‐negative (Escherichia coli, Bacillus subtilis) and Gram‐positive (Enterococcus durans) bacteria. Minimal inhibitory concentrations (MIC = 6.2 mg/mL) were found for complex cobalt chloride with allylbenzimidazole ligands against E. durans and E. coli. Its antimicrobial activity is several times higher compared to the reference gentamicin. Molecular docking made it possible to consider the nature of binding of cobalt metal complexes with vinyl‐, allyl‐ and styrylbenzimidazole ligands to biological targets and estimate their energy. The binding energy meanings depend on protein and ligand type, and reaches 8 kcal/mol.

AbstractA simple and mild protocol for the direct synthesis of vinyl nitriles is described. By employing potassium trimethylsilanolate as the mild base and benzyl chloride as the efficient promoter, a series of E‐configured vinyl nitriles are selectively obtained from readily available aldehydes and acetonitrile at room temperature without the aid of a transition metal catalyst. Mechanistical investigations reveal that this transformation may go through a Knoevenagel condensation process.

AbstractA pentadentate diamide ligand, N,N′‐di(pyridine‐2‐yl)pyridine‐2,6‐dicarboxamide (L1H2) and its tetranuclear Cu(II) complex [Cu4(L1)2(μ3‐OH)2(H2O)3(ClO4)](ClO4) ⋅ H2O are reported. X‐ray crystal structure of the complex reveals that it has an open‐book type architecture. Two central copper atoms are connected to each other by two hydroxo bridges. Each of these two hydroxo bridges also connects the two central copper atoms to one of the two terminal copper atoms. Variable temperature susceptibility measurements show that χMT decreases with the temperature, indicating a strong antiferromagnetic behavior. With the help of DFT calculations the magnetic data was analyzed using the spin Hamiltonian H=−2 J1S3 ⋅ S4 −2 J2(S3 ⋅ S1+ S3 ⋅ S2+ S4 ⋅ S1+ S4 ⋅ S2)−2 J3S1 ⋅ S2 (where subscripts 1 and 2 refer to the terminal copper atoms and 3 and 4 refer to the central copper atoms). The best fit was obtained with 2 J1=−322 cm−1, 2 J2=+34.8 cm−1, 2 J3=−8.8 cm−1 and g=2.18, indicating a δ‐type interaction between terminal copper atoms. The complex proves to be an avid binder of ct‐DNA, with apparent binding constant (Kapp) value estimated as 1.536×107 M−1. In vitro experiments indicate that the Cu(II) complex reduced the proliferation of HCT116 cells among other cell lines. This reduction of cell proliferation may be attributed to the enhancement of intracellular ROS, along with modulation and disruption of cell cycle associated proteins. SKC conceptualized the project, arranged funding and involved in overall coordination among collaborators, analyzing the data, and writing the paper. AM was involved in doing the experimental work on synthesis of the compounds, carrying out analytical and spectroscopic measurements, collecting X‐ray crystallographic data and DNA binding experiments. MS, SM and KDS were involved in study of anticancer activities of the complex. SS helped in refining X‐ray structure of the complex. MC did the magnetic measurements and analysis whereas AF did the DFT calculations.

AbstractXanthones, a class of polyketide derivatives characterized by a dibenzo‐γ‐pyrone core structure, are aromatic oxygenated cyclic compounds extensively found in nature. They are known for their diverse biological activities, including anti‐Alzheimer, antitumor, and antidiabetic properties, which have spurred extensive research into their therapeutic potential. One of the most significant challenges facing mankind currently is the development of antibiotic resistance in pathogenic microbes making microbial infections increasingly difficult to treat. The formation of biofilms enhances bacterial resistance to antibiotics, immune defenses, and environmental stresses. In this review, we have categorized xanthones, both of biological origin and synthesized, based on their structure and summarized the recent studies on their ability to inhibit Gram‐positive and ‐negative bacteria as well as the various underlying mechanisms that contribute to their microbicidal activity. These mechanisms include inhibition of virulence factors and biofilm formation, interaction with cell membranes, and interference with cell wall synthesis and DNA replication. In addition, we have listed the various methods involved in biofilm inhibition and the structure‐activity relationship of various xanthone molecules, highlighting how xanthone derivatives exhibit increased antibacterial activity. With the growing concern of antibiotic resistance, exploring natural compounds like xanthones to study their interaction with bacterial cells is crucial for identifying new treatment options.