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An intriguing example of a crystallization-induced stereochemical switch in the configuration of aza-Michael reaction products is described. Depending on both the stereochemical purity and stoichiometric ratio of the chiral amine used, the reaction delivers crystalline diastereomers of a different stereochemistry. The optically pure diastereomer smoothly converts to its racemic epimer salt upon the addition of a complementary chiral amine.
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http://dx.doi.org/10.1002/chir.23451 | DOI Listing |
Pharmaceuticals (Basel)
July 2025
Laboratory of Applied Chemistry and Environment (LCAE), Faculty of Science, University Mohammed Premier, Bd. Med VI B.P. 717, Oujda 60000, Morocco.
Oncogenic KRAS drives ~30% of solid tumours, yet the only approved G12C-specific drugs benefit ≈ 13% of KRAS-mutant patients, leaving a major clinical gap. We sought mutation-agnostic natural ligands from Ziziphus lotus, whose stereochemically rich phenolics may overcome this limitation by occupying the SI/II (Switch I/Switch II) groove and locking KRAS in its inactive state. Phytochemical mining yielded five recurrent phenolics, such as (+)-catechin, hyperin, astragalin, eriodictyol, and the prenylated benzoate amorfrutin A, benchmarked against the covalent inhibitor sotorasib.
View Article and Find Full Text PDFJ Am Chem Soc
July 2025
New Cornerstone Science Laboratory, State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China.
Construction of consecutive stereogenic centers with high diastereo- and enantioselectivities is a challenging task in organic synthesis. Ir-catalyzed asymmetric allylic substitution reactions with prochiral nucleophiles have evolved as an important method toward this goal. Herein, we report a Cu/Ir relay catalysis allowing for the utilization of alkylcopper reagents, in situ generated from Cu-mediated borylative difunctionalization of styrenes with Bpin, as nucleophiles compatible with π-allyl-Ir electrophiles derived from linear allyl carbonates.
View Article and Find Full Text PDFMolecules
June 2025
Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
Sucrose is by far the most abundant disaccharide found in nature, consisting of two simple hexose units: d-glucose and d-fructose. This exceptionally inexpensive and widely accessible raw material is produced in virtually limitless quantities. The vast majority is consumed in the food industry either in its native form-as commercial table sugar-or, to a lesser extent, as the basis for artificial sweeteners such as palatinose and sucralose.
View Article and Find Full Text PDFChemistry
September 2025
School of Chemistry, Pharmacy and Pharmacology, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
The dipyrromethenes (DPMs) and their borylated adducts (BODIPYs) constitute a class of versatile chromophores that has become one of the most widely studied over recent decades. They combine excellent photochemistry properties with opportunity for synthetic manipulation and tuning. We report here a related class of aza-dibenzodipyrromethenes and show that they present an interesting architecture where the core adopts a helical arrangement that places terminal aryl functional groups directly on top of each other in close, π-stacked arrangement.
View Article and Find Full Text PDFAnal Chem
July 2025
State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi 214122, China.
Chiral covalent-organic framework (COF) nanochannel membranes with ordered channels and predesigned structures play a pivotal role in enantioselective sensing. However, the enantioselectivity of chiral COFs is still limited due to the lack of chiral environment regulating. Herein, we report a self-standing chiral copper-coordinated COF (COF-Cu(II)) nanochannel membrane for the enantioselective sensing of reducing amino acids based on the synergistic integration of stereochemical recognition and redox-responsive signal amplification.
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