It is difficult to imagine organic chemistry without organo-halogen compounds and the molecular halogens needed for their preparation. The halogens have very different reactivity, with iodine usually requiring some form of activation, while others are reactive and hazardous chemicals. To avoid their use, various modified reagents have been discovered (N-bromo- and N-chlorosuccinimide, Selectfluor..), but halogens are used to prepare these reagents and when they are used the atom economy is poor. A better approach, which is based on biomimetric research on oxidative halogenation in nature, consists of generating the halogenating reagent in situ under acidic conditions from a halide salt. The result of such a reaction has been halogenation with 100 % halogen atom economy. Suitable oxidants for the oxidation of halides are hydrogen peroxide and oxygen.
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http://dx.doi.org/10.1002/anie.200901223 | DOI Listing |
J Nat Prod
December 2024
Anti-infective Agent Creation Engineering Research Centre of Sichuan Province, School of Pharmacy, Chengdu University, Chengdu 610106, China.
The first total syntheses of four isoflavone glucosides, tectoridin (), tectoridin A (), tectorigenin 7--β-d-glucopyranosyl-12--β-d-glucopyranoside (), and isotectroigenin 7--β-d-glucopyranoside (), have been accomplished. Key steps in our synthetic approach include a regioselective halogenation reaction, followed by methanolysis to introduce the -OCH group into isoflavone frameworks and a PTC-promoted stereoselective glycosidation to establish glycosidic bonds. The synthesized isoflavone glucosides (-) and their corresponding aglycones ( and ) were evaluated for anti-inflammatory activity against nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1 β (IL-1β) in lipopolysaccharide (LPS)-induced RAW264.
View Article and Find Full Text PDFMethods Protoc
December 2024
Department of Natural Sciences, University of South Carolina Beaufort, 1 University Boulevard, Bluffton, SC 29909, USA.
The multifunctional catalytic hemoglobin from the terebellid polychaete , also named dehaloperoxidase (DHP), utilizes the typical oxygen transport function in addition to four observed activities involved in substrate oxidation. The multifunctional ability of DHP is presently a rare observation, and there exists a limitation for how novel dehaloperoxidases can be identified from macrobenthic infauna. In order to discover more infaunal DHP-bearing candidates, we have devised a facilitated method for an accurate taxonomic identification that places visual and molecular taxonomic approaches in parallel.
View Article and Find Full Text PDFNanomaterials (Basel)
December 2024
Laboratory of Advanced Materials and Technology, Tomsk State University, Tomsk 634050, Russia.
Photocatalysis offers a powerful approach for water purification from toxic organics, hydrogen production, biosolids processing, and the conversion of CO into useful products. Further advancements in photocatalytic technologies depend on the development of novel, highly efficient catalysts and optimized synthesis methods. This study aimed to develop a laser synthesis technique for bismuth oxyhalide nanoparticles (NPs) as efficient and multifunctional photocatalysts.
View Article and Find Full Text PDFMetabolites
December 2024
Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, University of Bisha, Bisha 61922, Saudi Arabia.
TCIPP (tris(1,3-dichloro-2-propyl) phosphate) and TCEP (tris(2-chloroethyl) phosphate) are organophosphate ester flame retardants found in various consumer products, posing significant health and environmental risks through inhalation, ingestion, and dermal exposure. Research reveals these compounds cause oxidative stress, inflammation, endocrine disruption, genotoxicity, neurotoxicity, and potentially hepatotoxicity, nephrotoxicity, cardiotoxicity, developmental, reproductive, and immunotoxicity. This review summarizes the current knowledge on the toxicological mechanisms of TCIPP and TCEP and presents the latest data on their toxicological effects obtained in vitro and in vivo, using omic systems, and on the basis of computational modelling.
View Article and Find Full Text PDFSmall
December 2024
The Institute for Advanced Studies, Wuhan University, Wuhan, 430072, China.
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