The implementation of inexpensive, Earth-abundant metals in typical noble-metal-mediated chemistry is a major goal in homogeneous catalysis. A sustainable or green reaction that has received a lot of attention in recent years and is preferentially catalyzed by Ir or Ru complexes is the alkylation of amines by alcohols. It is based on the borrowing hydrogen or hydrogen autotransfer concept. Herein, we report on the Co-catalyzed alkylation of aromatic amines by alcohols. The reaction proceeds under mild conditions, and selectively generates monoalkylated amines. The observed selectivity allows the synthesis of unsymmetrically substituted diamines. A novel Co complex stabilized by a PN5 P ligand catalyzes the reactions most efficiently.
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http://dx.doi.org/10.1002/anie.201507955 | DOI Listing |
Sci Adv
January 2025
Department of Neuroscience, Helen Wills Neuroscience Institute, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA.
Homeostatic sleep regulation is essential for optimizing the amount and timing of sleep for its revitalizing function, but the mechanism underlying sleep homeostasis remains poorly understood. Here, we show that optogenetic activation of locus coeruleus (LC) noradrenergic neurons immediately increased sleep propensity following a transient wakefulness, contrasting with many other arousal-promoting neurons whose activation induces sustained wakefulness. Fiber photometry showed that repeated optogenetic or sensory stimulation caused a rapid reduction of calcium activity in LC neurons and steep declines in noradrenaline/norepinephrine (NE) release in both the LC and medial prefrontal cortex (mPFC).
View Article and Find Full Text PDFPhysiol Plant
January 2025
Laboratory of Plant Physiology, Universidad de Extremadura, Badajoz, Spain.
Plant sphingolipids are lipophilic membrane components essential for different cellular functions but they also act as signaling molecules in various aspects of plant development. However, the interaction between plant sphingolipids and abscission remains largely uncharacterized. Here, the possible role of sphingolipids in regulating fruit abscission was examined in the abscission zone (AZ) of olive fruit.
View Article and Find Full Text PDFVet Med Sci
January 2025
Department of Biochemistry, Faculty of Veterinary Medicine, Erzurum, Turkey.
Background: Isoproterenol (ISO) is a nonselective beta-adrenergic receptor agonist known for its vasodilatory effects. This experiment aims to investigate whether intrauterine ISO administration could alter vascular indices and follicular development in postpartum Holstein cows.
Objectives: The objectives are to evaluate the effects of intrauterine ISO administration on vascular changes and its impact on follicular development compared to placebo groups.
Nat Commun
January 2025
Centre for Medicines Discovery, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
Sphingosine-1-phosphate (S1P) is a signaling lysolipid critical to heart development, immunity, and hearing. Accordingly, mutations in the S1P transporter SPNS2 are associated with reduced white cell count and hearing defects. SPNS2 also exports the S1P-mimicking FTY720-P (Fingolimod) and thereby is central to the pharmacokinetics of this drug when treating multiple sclerosis.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Pediatrics, Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama, Yufu, Oita, 879-5593, Japan.
In the management of pregnancy, ritodrine has been used to prevent preterm birth, and magnesium sulfate (MgSO) has been used to prevent preterm labor and preeclampsia. Neonates born to mothers receiving these medications occasionally show an increase in serum potassium concentration. Recently, an elevated risk of neonatal hyperkalemia has been reported, particularly when ritodrine and MgSO are co-administered; however, the underlying mechanisms remain unclear.
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