The homolytic cleavage of C-C bonds adjacent to specific functional groups has lately emerged as a versatile approach for molecular diversification. Despite the ubiquity and synthetic utility of ketones, radical fragmentation of their α-C-C bonds has proven to be a formidable challenge. Here, we present a broadly applicable deacylative strategy designed to homolytically cleave aliphatic ketones of various complexities, including transformations of cycloalkanones into carboxylic acids tethered to C-centered free radicals that can be engaged in diverse radical-based processes. The method involves ketone activation through treatment with hydrogen peroxide, yielding -dihydroperoxides. Subsequent single-electron-transfer reduction mediated by a low-valent metal complex generates alkyl radicals that can be captured selectively with a radicophile of choice, including through catalytic cross-coupling. The logic of our deacylative functionalization is exemplified by the total synthesis of 14 natural products, one analogue, and two drugs starting from readily available natural products, showcasing its transformative power in complex settings. This approach obviates the need for complex reagents and allows the controlled conversion of ketones to reconstructed products, making the process highly applicable across a spectrum of domains.
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http://dx.doi.org/10.1021/jacs.4c15045 | DOI Listing |
Org Lett
January 2025
Key Laboratory of Chemical Biology and Traditional Chinese Medicine (Ministry of Educational of China), Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, China.
We disclose herein a chiral phosphoric-acid-catalyzed enantioselective addition reaction of alcohols to fluoroalkylated biaryl 1,3-oxoazepines, which furnished a wide range of bridged biaryls bearing a fluoroalkylated quaternary carbon stereocenter on the seven-membered ring in high yields (up to 99%) with excellent enantioselectivities (up to 98% ee). Our method can be used for the modification of several natural products and bioactive molecules. Preliminary studies revealed that the products obtained in this reaction exhibit good in vitro bioactivities against two plant pathogens.
View Article and Find Full Text PDFAnal Methods
January 2025
Department of Food Science and Postharvest Technology, School of Applied Sciences and Technology, Cape Coast Technical University, Cape Coast, Ghana.
This research examined the distinction between organic and conventional mango fruits, chips, and juice using portable near-infrared (NIR) spectroscopy. A comprehensive analysis was conducted on a sample of 100 mangoes (comprising 50 organic and 50 conventional) utilising a portable NIR spectrometer that spans a wavelength range from 900 to 1700 nm. The mangoes were assessed in their entirety and their juice and chip forms.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
Queensland Alliance for Environmental Health Sciences (QAEHS), The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland 4102, Australia.
Humans are constantly exposed to micro- and nanosized plastics (MNPs); however, there is still limited understanding of their fate within the body, partially due to limitations with current analytical techniques. The current study assessed the appropriateness of pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) analysis for the quantification of a range of polymers in human blood. An extraction protocol that reduced matrix interferences (false positives) of polyethylene (PE) and polyvinyl chloride (PVC) was developed and validated.
View Article and Find Full Text PDFMediators Inflamm
January 2025
Institute of Digestive Diseases, Xiyuan Hospital of China Academy of Chinese Medical Sciences, Beijing, China.
This study aims to reveal the potential molecular mechanisms of modified Gegen Qinlian decoction (MGQD) in relieving ulcerative colitis (UC). C57BL/6J mice were used to establish experimental colitis via dextran sodium sulfate (DSS). Body weight, disease activity index (DAI), spleen weight, colon length, and histopathologic features were measured to evaluate the therapeutic effects of MGQD on mice with UC.
View Article and Find Full Text PDFFront Immunol
January 2025
Institute of Structural Pharmacology and Traditional Chinese Medicine (TCM) Chemical Biology, Fujian Key Laboratory of Chinese Materia Medica, College of Pharmacy, Fujian University of Traditional Chinese Medicine, Fuzhou, China.
Object: Neuroinflammation mediated by microglia has emerged as a critical factor in ischemic stroke and neuronal damage. Gualou Guizhi Granule (GLGZG) has been shown to suppress inflammation in lipopolysaccharide (LPS)-activated microglia, though the underlying mechanisms and its protective effects against neuronal apoptosis remain unclear. This study aims to investigate how GLGZG regulates the Notch signaling pathway in microglia to reduce neuroinflammation and protect neurons from apoptosis.
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