Reaction of equimolar amounts of MnBr·4HO and HL ((3,5-dimethyl-1-pyrazol-1-yl)methanol) in a basic MeCN solution leads to the formation of [MnII4(L)Br(HO)] (1), whose metallic skeleton is a [MnII4] tetrahedron and cluster core a [MnII4(μ-O)] cubane. Replacing MnBr·4HO with Mn(OCMe)·4HO affords [MnIII2MnII12O(L)(OAc)] (2) which is best described as a series of edge-sharing [Mn] tetrahedra that have self-assembled into a linear array in which each [Mn] pair is 'twisted' with respect to its neighbours in a corkscrew-like manner. Employment of the triangle [MnIII3O(OAc)(py)](ClO) as a reactant instead of a Mn salt results in the formation of [MnIII14MnII4O(L)(HL)(OAc)(HO)] (3) whose core is comprised of three vertex-sharing [MnIII4] butterflies flanked on either side by one [MnIII4] cubane and one [MnIII2MnII2] tetrahedron. Dc magnetic susceptibility and magnetisation measurements of polycrystalline samples of 1-3 reveal the predominance of antiferromagnetic exchange interactions. For [Mn] (1) this leads to a diamagnetic ground state, while for [Mn] (3) competing exchange interactions result in Single-Molecule Magnet (SMM) behaviour with = 22 K.
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Pharmaceuticals (Basel)
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Department of Basic Sciences, Ponce Research Institute, Ponce Health Sciences University, Ponce, PR 00716, USA.
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January 2025
N. S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninsky Prosp. 31, 119991 Moscow, Russia.
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Clinic of Gastroenterology, Hepatology and Infectious Diseases, Medical Faculty, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany.
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December 2024
Department of Physiology and Cell Biology, Faculty of Health Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer Sheva 84105, Israel.
Voltage-Dependent Anion Channel 1 (VDAC1) is a mitochondrial outer membrane protein that plays a crucial role in regulating cellular energy metabolism and apoptosis by mediating the exchange of ions and metabolites between mitochondria and the cytosol. Mitochondrial dysfunction and oxidative stress are central features of neurodegenerative diseases. The pivotal functions of VDAC1 in controlling mitochondrial membrane permeability, regulating calcium balance, and facilitating programmed cell death pathways, position it as a key determinant in the delicate balance between neuronal viability and degeneration.
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Synthetic Biology of Microbial Natural Products, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI), PharmaScienceHub (PSH), Saarbrücken, Germany.
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