A Chan-Lam reaction has been used to prepare N-alkenyl-α,β-unsaturated nitrones, which undergo a subsequent thermal rearrangement to the corresponding tri- and tetrasubstituted pyridines. The optimization and scope of these transformations is discussed. Initial mechanistic experiments suggest a reaction pathway involving oxygen transfer followed by cyclization.
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http://dx.doi.org/10.3762/bjoc.11.226 | DOI Listing |
Molecules
December 2024
Department of Chemistry and Biochemistry, Augustana University, Sioux Falls, SD 57197, USA.
This study examined the chemoselectivity and diastereoselectivity of silyl nitronate alkenyn-nitroethers in Intramolecular Silyl Nitronate Cycloadditions (ISNCs) to produce isoxazole derivatives with interesting medicinal properties. These reactions resulted in the formation of either dihydrofuro[3,4-c]isoxazolines/isoxazolidines and/or alkynyl moieties attached to 2,5-dihydrofuryl carbonyls. This study also discerned the diastereoselectivities of the resulting cyclic adducts and compared them to previous findings.
View Article and Find Full Text PDFBioorg Chem
January 2025
CSIR- Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India. Electronic address:
Alantolactone and isoalantolactone are two isomeric sesquiterpene lactones that were isolated from Innula recemosa. Here, we are used for the semisynthesis of novel isoxazolidine hybrids of alantolactone and isoalantolactone through a two-step process: nitrone synthesis followed by nitrone 1,3-dipolar cycloaddition. The formation of the cycloadduct was well characterized via modern spectroscopic techniques such as HRMS, H NMR, C NMR, DEPT-90, DEPT-135, and 2D NMR.
View Article and Find Full Text PDFChempluschem
December 2024
Department of Drug Science and Technology, University of Turin, Via P. Giuria 9, 10125, Turin, Italy.
The existing synthetic protocols for the direct functionalization of carbon-based nanomaterials often entail limitations due to their harsh reaction conditions, which require the use of high temperatures for extended periods. This study aims to overcome these limitations by developing mild and efficient synthetic protocols around 1,3-dipolar cycloaddition. Beginning with the well-established azomethine ylide derivatization, we progress to the utilization of nitrile oxide, and of nitrone derivatives for the functionalization of reduced graphene oxide (rGO) as well as of nanodiamonds (NDs).
View Article and Find Full Text PDFChemistry
January 2025
Department of Chemistry, National Taiwan University, Taipei, 106319, Taiwan, R.O.C.
Front Neurosci
November 2024
Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, United States.
Our study investigated the therapeutic potential of OKN-007 in the SOD1 G93A mouse model of amyotrophic lateral sclerosis (ALS). The impact of OKN-007, known for its antioxidant, anti-inflammatory, and neuroprotective properties, was tested at two doses (150 mg/kg and 300 mg/kg) at onset and late-stage disease. Results demonstrated a significant delay in disease progression at both doses, with treated mice showing a slower advance to early disease stages compared to untreated controls.
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