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The synthesis and characterisation of copper(I) complexes of chiral pyridine-containing macrocyclic ligands (Pc-L*) and their use as catalysts in asymmetric cyclopropanation reactions are reported. All ligands and metal complexes were fully characterised, including crystal structures of some species determined by X-ray diffraction on single crystals. This allowed characterising the very different conformations of the macrocycles which could be induced by different substituents or by metal complexation. The strategy adopted for the ligand synthesis is very flexible allowing several structural modifications. A small library of macrocyclic ligands possessing the same donor properties but with either C(1) or C(2) symmetry was synthesized. Cyclopropane products with both aromatic and aliphatic olefins were obtained in good yields and enantiomeric excesses up to 99%.
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http://dx.doi.org/10.1039/c2dt32347h | DOI Listing |
Thromb Res
September 2025
Departamento de Química and Institute for advanced research in chemical Science (IAdChem), Facultad de Ciencias, Módulo 13, Universidad Autónoma de Madrid, 28049, Madrid, Spain.
Platelet integrin αIIbβ3 is the final common effector of arterial thrombosis: it switches from a low-affinity to a high-affinity state, binds fibrinogen, and initiates the outside-in signals that stabilize a growing clot. Calcium- and integrin-binding protein 1 (CIB1) emerged as the first endogenous partner of the αIIb cytoplasmic tail and is now recognized as a dual-role adaptor. At rest, Ca-free CIB1 tethers the inner membrane clasp and restrains premature integrin activation; after ligand engagement, Ca-bound CIB1 docks onto αIIb, recruits focal-adhesion kinase and amplifies Src-dependent cytoskeletal remodeling.
View Article and Find Full Text PDFOrg Biomol Chem
September 2025
Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK.
Zinc(II) bis(triazolyl)(pyridyl)amine (Zn(BTPA)) complexes on the end of α-amino-iso-butyric acid (Aib) foldamers are able to transfer chirality from bound anions to the helical foldamer body. Zn(BTPA) could be obtained by simple synthetic methodology that allowed a range of functional groups to be installed around the binding site, exemplified with a fluorophore, a macrocyclic bridge and Aib itself. Changing functional group did not prevent chiral ligands from controlling foldamer conformation, although differences in complexation kinetics and equilibria were observed.
View Article and Find Full Text PDFInorg Chem
September 2025
ICMol, Departament de Química Inorgànica, Universitat de València, C/Catedrático José Beltrán 2, 46980 Paterna, Spain.
The failure of the therapeutic administration of superoxide dismutase (SOD) and catalase (CAT) enzymes to prevent oxidative stress has fostered the development of metal complexes that are capable of mimicking their activity. In the present work, two new pyridine azacyclophane ligands capable of coordinating Cu and Fe to give rise to mimetics with high activities toward disproportionation of the superoxide anion or hydrogen peroxide, depending on the metal ion, have been prepared. Although the Cu complexes have some of the highest SOD activities reported to date, they are completely inactive toward HO disproportionation.
View Article and Find Full Text PDFJ Am Chem Soc
September 2025
State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China.
Metal-organic frameworks (MOFs) are distinguished by their structural diversity, tunable electronic properties, and exceptional performance in various applications. Notably, the electron-donating ability of ligands significantly enhances the ligand-to-metal charge transfer (LMCT) processes within these frameworks, thereby promoting efficient charge migration. Herein, we developed two electron-rich macrocyclic ligands derived from phenothiazine- and phenoxazine-functionalized calix[3]arenes, alongside their corresponding cobalt-coordinated MOFs.
View Article and Find Full Text PDFbioRxiv
August 2025
Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada.
Genetically-encoded libraries of peptide-derived macrocycles containing electrophile 'warheads' (cGELs) can be used to identify potent and selective covalent ligands for protein targets. Such cGELs are synthesized either by incorporation of unnatural amino acids that display mild electrophiles on their side chains or by chemical post-translational modification (cPTM) of mRNA or phage-displayed peptide libraries. Here we investigate fundamental barriers to the synthesis of cGELs.
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