The first asymmetric total synthesis of aspidosperma alkaloid (+)-winchinine B was achieved in 12 steps from commercially available materials. A new synthetic strategy which features an efficient aza-Michael addition, a ruthenium-catalyzed transfer dehydrogenation, and an intramolecular palladium-catalyzed oxidative coupling was adopted to install the ABC tricycle system. A one-pot process involving carbonyl reduction/iminium formation/intramolecular conjugate addition developed by our group was utilized to construct the D ring moiety.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/acs.joc.9b02462 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
A cross-sectional study on the correlation between internal cerebral vein asymmetry and hemorrhagic transformation following endovascular thrombectomy.
Front Neurol
January 2025
Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, China.
Introduction: Hemorrhagic transformation (HT) is a severe complication in patients with acute ischemic stroke due to large vessel occlusion (AIS-LVO) after endovascular treatment (EVT). We hypothesize that asymmetry of the internal cerebral veins (ICVs) on baseline CT angiogram (CTA) may serve as an adjunctive predictor of HT.
Methods: We conducted a study on consecutive AIS-LVO patients from November 2020 to April 2022.
Comparative analysis of FACT devices for optimal improvement of power quality in unbalanced distribution systems.
Sci Rep
January 2025
Electrical Power and Machines Department, Faculty of Engineering-Tanta University, Tanta, Egypt.
This study examines the performance of asymmetric three-phase distribution systems under the influence of FACT deives such as a static VAR compensator (SVC) and a unified power controller (UPC). Each suggested device's operating principle is developed in this paper in order to provide the best model to be used in the power flow analysis. The performance of the IEEE-13 bus imbalanced distribution model is investigated using the Newton-Raphson method.
View Article and Find Full Text PDFIdiopathic normal pressure hydrocephalus concomitant with progressive supranuclear palsy.
Parkinsonism Relat Disord
January 2025
Department of Neurology, Juntendo University School of Medicine, Tokyo, Japan. Electronic address:
Introduction: Recent studies by us and others have unveiled a frequent coexistence of idiopathic normal pressure hydrocephalus (iNPH) with neurodegenerative movement disorders, including progressive supranuclear palsy (PSP). This study aims to explore the clinical and radiological characteristics of patients with iNPH who also had comorbid with PSP, referred to as iNPHc + PSP.
Methods: We retrospectively analyzed patients with iNPH admitted to our department between 2009 and 2024.
Tracking acute flaccid paralysis in Niger: a half-decade epidemiological portrait (2016-2021).
BMC Infect Dis
January 2025
Bureau de L'Organisation Mondiale de La Santé (OMS), Niamey, Niger.
Background: Recently, a total of 74 circulating vaccine-derived poliovirus (cVDPV) outbreaks were detected in 39 countries, with 672 confirmed Acute Flaccid Paralysis (AFP) cases identified in 27 countries. Despite progress, Niger experienced cVDPV outbreaks in 2018, highlighting the importance of maintaining AFP surveillance as a tool for polio eradication. This analysis aims to comprehensively assess AFP surveillance trends, patterns, and challenges in Niger, offering insights for public health initiatives in conflict-affected contexts.
View Article and Find Full Text PDFPeroxycarbenium-Mediated Asymmetric Synthesis of 1,2-Dioxanes and 1,2-Dioxolanes.
J Am Chem Soc
January 2025
BioCIS, Faculté de Pharmacie, Université Paris-Saclay, CNRS, Orsay 91400, France.
The endoperoxide scaffold is found in numerous natural products and synthetic substances of pharmaceutical interest. The main challenge to their synthetic access remains the preparation of chiral compounds due to the weakness of the peroxide bond, which limits the scope of available or applicable methods. Here, we demonstrate how peroxycarbenium species can be trapped by silylated nucleophiles with high enantioselectivities and diastereoselectivities when applicable, using a chiral imidophosphorimidate (IDPi) as a catalyst.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!