Unsaturated bicyclic endoperoxides are efficiently cyclopropanated with excess diazomethane in the presence of catalytic Pd(OAc) in a stereoselective manner. This method represents a new peroxide preserving transformation. Whereas the unsaturated endoperoxides in the [2.2.1] series are attacked by the carbene from the face, the analogs with larger bridges are preferentially attacked from the face to the peroxo bridge. Only in the case of the benzannelated [2.2.2] system the attack occurs exclusively from the face proximal to the benzene ring. Certain strained cyclopropanated endoperoxides are reduced by diazomethane to give -diols. 1-Methylfuran endoperoxide gives rise to -1-formyl-2-acetylcyclopropane in excellent yield.
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http://dx.doi.org/10.1002/adsc.200800804 | DOI Listing |
Int Immunopharmacol
January 2025
Sino-French Hoffmann Institute, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou 511436, China; The Second Affiliated Hospital of Guangzhou Medical University, State Key Laboratory of Respiratory Disease, Guangdong Provincial Key Laboratory of Allergy & Clinical Immunology, Guangzhou Medical University, Guangzhou 510260, China. Electronic address:
Artemisitene (ATT), an artemisinin (ART) analog retaining the endoperoxide moiety and incorporating an additional α, β-unsaturated carbonyl structure, exhibits enhanced biological activities. However, its therapeutic effects on liver fibrosis remain unclear. In this study, we demonstrated that ATT significantly alleviated liver inflammation and fibrosis induced by carbon tetrachloride (CCL) in mice.
View Article and Find Full Text PDFParasit Vectors
August 2024
Sino-French Hoffmann Institute, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, 511436, China.
Background: Artemisinin (ART) analogs, such as dihydroartemisinin, arteether, artemether, and artesunate, all featuring an endoperoxide bridge, have demonstrated efficacy against schistosomiasis. Artemisitene (ATT), which contains an additional α, β-unsaturated carbonyl structure, has shown enhanced biological activities. This study aims to evaluate the anti-schistosomaiasis japonica activity of ATT and compare it with ART.
View Article and Find Full Text PDFMolecules
June 2024
Department of Pharmacy, Section for Pharmaceutical Chemistry, University of Oslo, P.O. Box 1068, 0316 Oslo, Norway.
Research over the last 25 years related to structural elucidations and biological investigations of the specialized pro-resolving mediators has spurred great interest in targeting these endogenous products in total synthesis. These lipid mediators govern the resolution of inflammation as potent and stereoselective agonists toward individual G-protein-coupled receptors, resulting in potent anti-inflammatory activities demonstrated in many human disease models. Specialized pro-resolving mediators are oxygenated polyunsaturated products formed in stereoselective and distinct biosynthetic pathways initiated by various lipoxygenase and cyclooxygenase enzymes.
View Article and Find Full Text PDFACS Sens
May 2024
State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Beijing Key Laboratory of Active Substance Discovery and Druggability Evaluation, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
The smart light-up probes have been extensively developed to image various enzymes and other bioactive molecules. Upon activation, these probes result in light-up fluorophores that exist in a protein-bound or a free form. The difference between these two forms has not yet been reported.
View Article and Find Full Text PDFPharmacol Ther
April 2024
CNTTI of the Institute of Life Sciences & Department of Anesthesia of the Second Affiliated Hospital, Chongqing Medical University, Chongqing 400016, China; Basic Medicine Research and Innovation Center for Novel Target and Therapeutic Intervention, Ministry of Education, Chongqing 400016, China; College of Pharmacy, Chongqing Medical University, Chongqing 400016, China. Electronic address:
Oxylipins have garnered increasing attention because they were consistently shown to play pathological and/or pharmacological roles in the development of multiple cancers. Oxylipins are the metabolites of polyunsaturated fatty acids via both enzymatic and nonenzymatic pathways. The enzymes mediating the metabolism of PUFAs include but not limited to lipoxygenases (LOXs), cyclooxygenases (COXs), and cytochrome P450s (CYPs) pathways, as well as the down-stream enzymes.
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