The nature and extent of covalency in uranium bonding is still unclear compared with that of transition metals, and there is great interest in studying uranium-ligand multiple bonds. Although U=O and U=NR double bonds (where R is an alkyl group) are well-known analogues to transition-metal oxo and imido complexes, the uranium(VI)-nitride triple bond has long remained a synthetic target in actinide chemistry. Here, we report the preparation of a uranium(VI)-nitride triple bond. We highlight the importance of (1) ancillary ligand design, (2) employing mild redox reactions instead of harsh photochemical methods that decompose transiently formed uranium(VI) nitrides, (3) an electrostatically stabilizing sodium ion during nitride installation, (4) selecting the right sodium sequestering reagent, (5) inner versus outer sphere oxidation and (6) stability with respect to the uranium oxidation state. Computational analyses suggest covalent contributions to U≡N triple bonds that are surprisingly comparable to those of their group 6 transition-metal nitride counterparts.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1038/nchem.1642 | DOI Listing |
Cardiovasc Intervent Radiol
January 2025
Department of Diagnostic and Interventional Radiology, Faculty of Medicine, Medical Center - University of Freiburg, University of Freiburg, Hugstetter Str. 55, 79106, Freiburg, Germany.
Cell Death Differ
January 2025
Laboratory of Hematology-Oncology, European Institute of Oncology IRCCS, Via Ripamonti 435, 20141, Milan, Italy.
Immunity suffers a function deficit during aging, and the incidence of cancer is increased in the elderly. However, most cancer models employ young mice, which are poorly representative of adult cancer patients. We have previously reported that Triple-Therapy (TT), involving antigen-presenting-cell activation by vinorelbine and generation of TCF1-stem-cell-like T cells (scTs) by cyclophosphamide significantly improved anti-PD-1 efficacy in anti-PD1-resistant models like Triple-Negative Breast Cancer (TNBC) and Non-Hodgkin's Lymphoma (NHL), due to T-cell-mediated tumor killing.
View Article and Find Full Text PDFAm J Obstet Gynecol MFM
January 2025
Instituto de Medicina Integral Prof. Fernando Figueira (IMIP), Recife, Pernambuco, Brazil.
Background: Preeclampsia is a major hypertensive disorder of pregnancy, which may lead to severe complications, particularly in the first two weeks of the postpartum period. During the postpartum period, blood pressure levels remain high, often increasing to levels higher than those experienced during pregnancy. Furosemide, a fast-acting diuretic, reduces the intravascular volume overload and may represent an alternative to accelerate the normalization of blood pressure levels.
View Article and Find Full Text PDFJ Adv Res
January 2025
Cancer Institute, Xuzhou Medical University, 209 Tongshan Road, Xuzhou 221004 Jiangsu, China; Center of Clinical Oncology, The Afliated Hospital of Xuzhou Medical University, 99 West Huaihai Road, Xuzhou 221002 Jiangsu, China; Jiangsu Center for the Collaboration and Innovation of Cancer Biotherapy, Xuzhou Medical University, 209 Tongshan Road, Xuzhou 221004 Jiangsu, China. Electronic address:
Introduction: Hypericin (HP), a natural photosensitizer, has demonstrated great efficacy in photodynamic therapy (PDT) for cancer treatment. In addition to the induction of apoptosis and necrosis through reactive oxygen species (ROS) generation, the therapeutic mechanisms and targets of PDT-HP remain unknown.
Objectives: To investigate the direct targets and mechanisms of action of photoactivated hypericin in the inhibition of triple-negative breast cancer (TNBC).
Acta Biomater
January 2025
School of Pharmaceutical Sciences (Shenzhen), Shenzhen Campus of Sun Yat-sen University, Shenzhen, 518107, China; School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Guangzhou, 510275, China. Electronic address:
Following cerebral ischemia, reperfusion injury can worsen ischemia-induced functional, metabolic disturbances, and pathological damage upon blood flow restoration, potentially leading to irreversible harm. Yet, there's a dearth of advanced, localized drug delivery systems ensuring active pharmaceutical ingredient (API) efficacy in cerebral protection during ischemia-reperfusion. This study introduces a multivalent bioadhesive nanoparticle-cluster, merging bioadhesive nanoparticles (BNPs) with dendritic polyamidoamine (PAMAM), enhancing nose-to-brain delivery and brain protection efficacy against cerebral ischemia-reperfusion injuries (CIRI).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!