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In this study, we report the synthesis and comprehensive characterization of a novel binuclear copper(II) complex (LCu) featuring a Schiff base ligand derived from glycine. The complex was synthesized through a one-pot method and characterized using various techniques, including single-crystal X-ray diffraction (SCXRD), FTIR spectroscopy, thermal analysis, UV-Vis spectroscopy, and electron paramagnetic resonance (EPR). SCXRD analysis revealed a distinctive dimeric structure, with each copper center displaying a slightly distorted square pyramidal geometry. Spectroscopic techniques (FTIR, UV-Vis, EPR) corroborated the coordination environment of the copper ions. Computational studies, including non-covalent interaction (NCI) analysis and time-dependent density functional theory (TD-DFT) calculations, provided further insights into the electronic structure and stability of the complex. Catalytic tests of LCu were conducted in two key reactions: olefin cyclopropanation and C–S cross-coupling. The cyclopropanation reaction showed high yields, outstanding chemoselectivity, and exceptional trans diastereoselectivity, with a trans/cis ratio exceeding 1000 : 1. The C–S cross-coupling reaction also exhibited high conversion rates (over 93%) and yields (above 92%). These findings underscore the efficiency and versatility of LCu as a catalyst, with potential applications in sustainable synthetic processes. [ABSTRACT FROM AUTHOR]

Public health, production and preservation of food, development of environmentally friendly (cosmeto-)textiles and plastics, synthesis processes using green technology, and improvement of water quality, among other domains, can be controlled with the help of chitosan. It has been demonstrated that this biopolymer exhibits advantageous properties, such as biocompatibility, biodegradability, antimicrobial effect, mucoadhesive properties, film-forming capacity, elicitor of plant defenses, coagulant-flocculant ability, synergistic effect and adjuvant along with other substances and materials. In part, its versatility is attributed to the presence of ionizable and reactive primary amino groups that provide strong chemical interactions with small inorganic and organic substances, macromolecules, ions, and cell membranes/walls. Hence, chitosan has been used either to create new materials or to modify the properties of conventional materials applied on an industrial scale. Considering the relevance of strategic topics around the world, this review integrates recent studies and key background information constructed by different researchers designing chitosan-based materials with potential applications in the aforementioned concerns. [ABSTRACT FROM AUTHOR]

A new acyclic bismuth complex (Bi-edtabz) was synthesized from a mixture of solutions of the ligand (EDTA-based phenylene) and bismuth under acidic conditions. Its anti-virulence properties were evaluated against Escherichia coli O157: H7, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella enterica sub. enterica serovar Typhimurium and Staphylococcus aureus. The bismuth complex was characterized by NMR, UV-Vis, FTIR, ESI/MS and TG. Furthermore, Bi-edtabz complex at 0.25-1 mM presented better antibiofilm properties against E. coli O157: H7 and S. aureus with values of biomass reduction of 30.1-57.1% and 37.8-55.5%, respectively, compared with the ligand edtabz. While biofilm formation of L. monocytogenes, P. aeruginosa and Salmonella Typhimurium was most impaired by edtabz (biomass reduction of 66.1-100%, 66.4-88.0% and 50.9-67.1%), respectively. Additionally, Bi-edtabz inhibited the swimming motility of E. coli O157: H7 (12.5%) and colony spread of S. aureus (47.2%) at 1mMand inhibited violacein production, a quorum-sensing related pigment of the biosensor strain Chromobacterium violaceum. Hence, edtabz and the Bi-edtabz complex can be used as novel anti-virulence agents against pathogenic bacteria. [ABSTRACT FROM AUTHOR]

Synthetic molecules that mimic the function of natural enzymes or molecules have untapped potential for use in the next generation of drugs. Cyclic compounds that contain aromatic rings are macrocyclic cyclophanes, and when they coordinate iron ions are of particular interest due to their antioxidant and biomimetic properties. However, little is known about the molecular responses at the cellular level. This study aims to evaluate the changes in immune gene expression in human cells exposed to the cyclophanes Fe2PO and Fe2PC. Confluent human embryonic kidney cells were exposed to either the cyclophane Fe2PO or Fe2PC before extraction of RNA. The expression of a panel of innate and adaptive immune genes was analyzed by quantitative real-time PCR. Evidence was found for an inflammatory response elicited by the cyclophane exposures. After 8 h of exposure, the cells increased the relative expression of inflammatory mediators such as interleukin 1; IRAK, which transduces signals between interleukin 1 receptors and the NFκB pathway; and the LPS pattern recognition receptor CD14. After 24 h of exposure, regulatory genes begin to counter the inflammation, as some genes involved in oxidative stress, apoptosis and non-inflammatory immune responses come into play. Both Fe2PO and Fe2PC induced similar immunogenetic changes in transcription profiles, but equal molar doses of Fe2PC resulted in more robust responses. These data suggest that further work in whole animal models may provide more insights into the extent of systemic physiological changes induced by these cyclophanes. [ABSTRACT FROM AUTHOR]

1,2,3-Benzotriazinones were synthesized in excellent yields by the reaction of 2-(o-aminophenyl)oxazolines and isoamyl nitrite in methanol. The crystal structure of the acetyl derivative of one of the 1,2,3-benzotriazinones provided additional support for the spectroscopic structural characterization of the title compounds. [ABSTRACT FROM AUTHOR]

Fractions from an organic extract from fresh octopus (Paraoctopus limaculatus) were studied for biological activities such as antimutagenic and antiproliferative properties using Salmonella tester strains TA98 and TA100 with metabolic activation (S9) and a cancer cell line (B-cell lymphoma), respectively. A chloroform extract obtained from octopus tentacles was sequentially fractionated using thin layer chromatography (TLC), and each fraction was tested for antimutagenic and antiproliferative activities. Organic extract reduced the number of revertants caused by aflatoxin B1 showing a dose-response type of relationship. Sequential TLC fractionation of the active extracts produced several antimutagenic and/ or antiproliferative fractions. Based on the results obtained, the isolated fractions obtained from octopus contain compounds with chemoprotective properties that reduce the mutagenicity of AFB1 and proliferation of cancer cell lines. [ABSTRACT FROM AUTHOR]

Two new glycine-Schiff base copper(II) complexes were synthesized. Single crystal X-ray diffraction (SCXRD) allowed us to establish the structure of both complexes in the solid state. The glycine-Schiff base copper(II) complex derived from 2′-hydroxy-5′-nitroacetophenone showed a mononuclear hydrated structure, in which the Schiff base acted as a tridentate ligand, and the glycine-Schiff base copper(II) complex derived from 2′-hydroxy-5′-methylacetophenone showed a less common tetranuclear anhydrous metallocyclic structure, in which the Schiff base acted as a tetradentate ligand. In both compounds, copper(II) had a tetracoordinated square planar geometry. The results of vibrational, electronic, and paramagnetic spectroscopies, as well as thermal analysis, were consistent with the crystal structures. Both complexes were evaluated as catalysts in the olefin cyclopropanation by carbene transference, and both led to very high diastereoselectivity (greater than 98%). [ABSTRACT FROM AUTHOR]

Purpose: To isolate and evaluate the antimutagenic properties of compounds previously identified in octopus (Paraoctopus limaculatus). Methods: Octopus fractions, previously obtained by a sequential thin layer chromatography (TLC) procedure, were subjected to further fractionation by TLC and their anti-mutagenic activity monitored using Salmonella tester strains TA98 and TA100 with metabolic activation (S9) in Ames test. The isolated fractions were subjected to structural studies by Fourier transformed infrared spectroscopy (FTIR), nuclear magnetic resonance (¹H and 13C NMR), and gas chromatography-mass spectrometry. Results: Five new fractions were obtained from a previously isolated and reported anti-mutagenic octopus fraction. Fractions RB21321b2 and RB21321b3 inhibited > 80 % of the mutagenicity induced by 500 ng AFB1 on both tester strains and were selected for chemical/structural characterization. Data from IR and ¹H and 13C NMR suggested the presence of phthalate type of compounds. GC-MS analysis revealed 278 m/z for both fractions which is consistent with a butyl isobutyl phthalate structure. Conclusion: Based on the findings, the compound responsible for the high anti-mutagenic activity of the isolated fraction from octopus is 1-butyl-2-isobutyl-phthalate. [ABSTRACT FROM AUTHOR]

Synthetic molecules that mimic the function of natural enzymes or molecules have untapped potential for use in the next generation of drugs. Cyclic compounds that contain aromatic rings are macrocyclic cyclophanes, and when they coordinate iron ions are of particular interest due to their antioxidant and biomimetic properties. However, little is known about the molecular responses at the cellular level. This study aims to evaluate the changes in immune gene expression in human cells exposed to the cyclophanes Fe 2 PO and Fe 2 PC. Confluent human embryonic kidney cells were exposed to either the cyclophane Fe 2 PO or Fe 2 PC before extraction of RNA. The expression of a panel of innate and adaptive immune genes was analyzed by quantitative real-time PCR. Evidence was found for an inflammatory response elicited by the cyclophane exposures. After 8 h of exposure, the cells increased the relative expression of inflammatory mediators such as interleukin 1; IRAK, which transduces signals between interleukin 1 receptors and the NFκB pathway; and the LPS pattern recognition receptor CD14. After 24 h of exposure, regulatory genes begin to counter the inflammation, as some genes involved in oxidative stress, apoptosis and non-inflammatory immune responses come into play. Both Fe 2 PO and Fe 2 PC induced similar immunogenetic changes in transcription profiles, but equal molar doses of Fe 2 PC resulted in more robust responses. These data suggest that further work in whole animal models may provide more insights into the extent of systemic physiological changes induced by these cyclophanes., Competing Interests: Rogerio R. Sotelo-Mundo is an Academic Editor for PeerJ. Christie M. Sayes is employed by RTI International. The authors declare that they have no competing interests., (© 2020 Salazar-Medina et al.)

The crystal structure of the title compound, C(11)H(13)N(3)O(2), is stabilized by O-H⋯O hydrogen bonds, which link the mol-ecules into chains along [100].

In the solid state, the structure of the title compound, C(16)H(18)N(4)O(2), is stabilized by inter-molecular N-H⋯O and O-H⋯O hydrogen bonds. These hydrogen bonds arrange the mol-ecules into a double-layer supra-molecular structure. The mol-ecular conformation is is consolidated by an intra-molecular N-H⋯N hydrogen bond. The dihedral angle between the aromatic rings is 8.01 (10)°