A substituted TREN has been prepared in which the aryl groups in (ArylNHCH2CH2)3N are substituted at the 3- and 5-positions with a total of six OCH2(CH2)nCH═CH2 groups (n = 1, 2, 3). Molybdenum nitride complexes, [(ArylNCH2CH2)3N]Mo(N), have been isolated as adducts that contain B(C6F5)3 bound to the nitride. Two of these [(ArylNCH2CH2)3N]Mo(NB(C6F5)3) complexes (n = 1 and 3) were crystallographically characterized. After removal of the borane from [(ArylNCH2CH2)3N]Mo(NB(C6F5)3) with PMe3, ring-closing olefin metathesis (RCM) was employed to join the aryl rings with OCH2(CH2)nCH═CH(CH2)nCH2O links (n = 1-3) between them. RCM worked best with a W(O)(CHCMe3)(Me2Pyr)(OHMT)(PMe2Ph) catalyst (OHMT = hexamethylterphenoxide, Me2Pyr = 2,5-dimethylpyrrolide) and n = 3. The macrocyclic ligand was removed from the metal through hydrolysis and isolated in 70-75% yields relative to the borane adducts. Crystallographic characterization showed that the macrocyclic TREN ligand in which n = 3 contains three cis double bonds. Hydrogenation produced a TREN in which the three links are saturated, i.e., O(CH2)10O.
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Free Radic Biol Med
December 2024
Instituto de Bioquímica y Microbiología, UACh, Valdivia, Chile; Center for Interdisciplinary Studies on Nervous System (CISNe), UACh, Valdivia, Chile; Janelia Research Campus HHMI, Ashburn, VA, USA. Electronic address:
Huntington's disease (HD) is a neurodegenerative disorder caused by a CAG trinucleotide repeat expansion in the first exon of the huntingtin gene. The huntingtin protein (Htt) is ubiquitously expressed and localized in several organelles, including endosomes, where it plays an essential role in intracellular trafficking. Presymptomatic HD is associated with a failure in energy metabolism and oxidative stress.
View Article and Find Full Text PDFJ Neuroimmunol
October 2024
Translational Immunology Research Program, University of Helsinki, Helsinki, Finland; Department of Neurology, Neurocenter, Helsinki University Hospital, Helsinki, Finland.
The coagulation cascade and fibrinolysis have links with neuroinflammation and increased activation of the coagulation system has been reported in MS patients. We quantified levels of D-dimer, tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1) and the bioactivity of bacterial lipopolysaccharide (LPS) in cerebrospinal fluid (CSF) and plasma from newly diagnosed untreated MS patients and controls. These molecules showed multiple correlations with each other as well as with age, HLA-DRB1*15:01, body-mass-index and CSF IgG.
View Article and Find Full Text PDFChemistry
September 2024
Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany.
A series of titanium μ-nitrido complexes supported by the triamidoamine ligand Xy-NN (Xy-NN={(3,5-MeCH)NCHCH}N) is reported. The titanium azido complex [(Xy-NN)TiN] (1-N), prepared by salt metathesis of the chloride complex [(Xy-NN)TiCl] (1-Cl) with NaN, reacted with lithium metal or with alkali metal naphthalenides (alkali metal M=Na, K, and Rb) in THF to give the corresponding dinuclear μ-nitrido complexes M[(Xy-NN)Ti=N-Ti(Xy-NN)] (2-M; M=Li, Na, K, Rb). Single crystal X-ray diffraction studies of 2-Li, 2-Na, and 2-K revealed alkali metal dependent structures in the solid state.
View Article and Find Full Text PDFCommun Chem
April 2024
WestCHEM, Department of Pure & Applied Chemistry, University of Strathclyde, Glasgow, G1 1XL, UK.
Recently main group compounds have stepped into the territory of precious transition metal compounds with respect to utility in the homogeneous catalysis of fundamentally important organic transformations. Inspired by the need to promote more sustainability in chemistry because of their greater abundance in nature, this change of direction is surprising since main group metals generally do not possess the same breadth of reactivity as precious transition metals. Here, we introduce the dihydropyridylsodium compound, Na-1,2-tBu-DH(DMAP), and its monomeric variant [Na-1,2-tBu-DH(DMAP)]·MeTREN, and demonstrate their effectiveness in transfer hydrogenation catalysis of the representative alkene 1,1-diphenylethylene to the alkane 1,1-diphenylethane using 1,4-cyclohexadiene as hydrogen source [DMAP = 4-dimethylaminopyridine; MeTREN = tris(N,N-dimethyl-2-aminoethyl)amine].
View Article and Find Full Text PDFAcc Chem Res
March 2024
Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States.
Nuclear medicine harnesses radioisotopes for the diagnosis and treatment of disease. While the isotopes Tc and In have enabled the clinical diagnosis of millions of patients over the past 3 decades, more recent clinical translation of numerous Ga/Lu-based radiopharmaceuticals for diagnostic imaging and therapy underscores the clinical utility of metal-based radiopharmaceuticals in mainstream cancer treatment. In addition to such established radionuclides, advancements in radioisotope production have enabled the production of radionuclides with a broad range of half-lives and emission properties of interest for nuclear medicine.
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