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Embedding medical and hygiene products with regenerable antimicrobial functions would have significant implications for limiting pathogen contaminations and reducing healthcare-associated infections. Herein, we demonstrate a scalable and industrially feasible methodology to fabricate chlorine rechargeable melt-blown polypropylene (PP) nonwoven fabrics, which have been widely used in hygienic and personal protective products, via a combination of a melt reactive extrusion process and melt-blown technique. Methacrylamide (MAM) was employed as a precursor of halamine monomers and covalently grafted onto the PP backbone to form polypropylene-grafted methacrylamide (PP-g-MAM), which could be chlorinated, yielding biocidal acyclic halamines. click here Subsequently, the resultant PP-g-MAM was manufactured into nonwoven fabrics with varying fiber diameters by adjusting the hot air flowing speed during the melt-blowing process. The chlorinated nonwoven fabrics (PP-g-MAM-Cl) exhibited integrated properties such as a robust mechanical property, good thermal stability, high chlorination capability (>850 ppm), and desirable chlorine rechargeability. More importantly, such chlorinated nonwoven fabrics showed a promising antibacterial and antiviral efficiency, achieving 6 log CFU reduction of bacteria (both Escherichia coli O157 H7 and Listeria innocua) and 7 log PFU reductions of a virus (T7 bacteriophages) within 15 and 5 min of contact, respectively, revealing great potential to serve as a reusable antimicrobial material for medical protection applications.Aqueous solutions of equimolar mixtures of 2,4,6-triaminopyrimidine (TAP) and carboxylic acid substituted cyanuric acid (CyCo6 or R-4MeCyCo6) monomers self-assemble into gel-forming supramolecular polymers. Macroscopic fibers drawn from these mixtures were analyzed by X-ray diffraction to determine their molecular structures. Computational methods were used to explore the intrinsic intermolecular interactions that contribute to the structure and stability of these assemblies. Both polymers are formed by the stacking of hexameric rosettes, (TAP/CyCo6)3 or (TAP/R-4MeCyCo6)3, respectively, into long, stiff, twisted stacks of essentially planar rosettes. Chiral, left-handed supramolecular polymers with a helical twist angle of -26.7° per hexad are formed when the pure enantiomer R-4MeCyCo6 is used. These hexad stacks pack into bundles with a hexagonal crystalline lattice organization perpendicular to the axis of the macroscopic fiber. Polymers formed from TAP and CyCo6, both of which are achiral, assemble into macroscopic domains that are packed as a centered rectangular lattice. Within these domains, the individual polymers exist as either right-handed or left-handed helical stacks, with twist angles of +15° or -15° per hexad, respectively. The remarkable ability of TAP and cyanuric acid derivatives to self-assemble in water, and the structural features of their supramolecular polymers reported here, provide additional support for the proposal that these heterocycles could have served as recognition units for an early form of nucleic acids, before the emergence of RNA.In projected structure-activity relationship studies of the novel diheteroarylamide-based anti-HIV agent 2 (1C8), one objective was to evaluate the influence of incorporating the central amide motif in 2 into a five-membered pyrazolone ring, as found in 3. It was envisaged that compound 3 could be prepared through reaction of 3-hydrazino-5-nitrobenzisothiazole 5 with the methyl ester of 4-chloropyridine-3-carboxylic acid, followed by N-methylation of the pyridine nitrogen. However, the reaction of 3-methoxyl-5-nitrobenzisothiazole with hydrazine resulted in formation of ring-opened hydrazonate product 18. In the corresponding reaction with 3-chloro-5-nitrobenzisothiazole, a different rearrangement product 19 was formed, in which two 2,1-benzisothiazole units are joined by a sulfur bridge. Meisenheimer complex formation, favored by the presence of the 5-nitro substituent on the benzisothiazole ring, was postulated to be a key feature in the formation of these deep-seated rearrangement products. Support for the proposed formation of the pivotal Meisenheimer complexes and their subsequent evolution to the observed products in which the benzisothiazole sulfur atom is either expelled or maintained in the isomeric 2,1-benzisothiazole system was obtained by density function theory calculations.Cholinesterases are significant biological targets for the regulation of cholinergic neurotransmission, and their inhibitors are being exploited for the management of cognitive decline in various neurological conditions. The 1,4-benzoquinone scaffold possesses antioxidant potential along with AChE inhibition activity in various neurological disorders. To design novel and potent selective 1,4-benzoquinone analogues as cholinesterase inhibitors, a ligand-based drug design strategy was followed to develop a 3D quantitative structure-selectivity relationship (QSSR) model. On the basis of the best fit model, eight novel 1,4-benzoquinone derivatives were designed and synthesized implementing appropriate synthetic procedures and were characterized by various spectral and elemental techniques. All the synthesized compounds were evaluated for their selective in vitro acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory potential at different concentrations using mice brain homogenate as the source oequired for the selectivity of AChE inhibitors over BChE. The outcome of this study may be used as a novel tool to design new highly selective and more potent molecules.We report a novel heterogeneous adsorption mechanism of formic acid on the magnetite (111) surface. Our experimental results and density functional theory (DFT) calculations give evidence for dissociative adsorption of formic acid in quasibidentate and chelating geometries. The latter is induced by the presence of iron vacancies at the surface, making oxygen atoms accessible for hydrogen atoms from dissociated formic acid. DFT calculations predict that both adsorption geometries are energetically favorable under our experimental conditions. The calculations prove that the locally observed (√3 × √3)R 30° superstructure consists of three formate molecules in a triangular arrangement, adsorbed predominantly in a chelating geometry. The results show how defects can stabilize alternative adsorption geometries, which is a crucial ingredient for a detailed atomistic understanding of reaction barriers on magnetite and other oxide surfaces, as well as for the stability of carboxylic acid based nanocomposite materials.