A method for the stereoselective synthesis of 2,6-disubstituted piperidines has been developed that is based on the use of an intramolecular iridium-catalyzed allylic substitution as a configurational switch. The procedure allows the preparation of 2-vinylpiperidines with enantiomeric excesses (ee) of greater than 99%. As applications, total syntheses of piperidine alkaloids have been elaborated, most often by using Ru-catalyzed cross-metatheses as a key step for introduction of a side chain. Asymmetric total syntheses of the prosopis alkaloids (+)-prosopinine, (+)-prosophylline, (+)-prosopine, and of the dendrobate alkaloid (+)-241D and its C6 epimer are described.
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http://dx.doi.org/10.1002/chem.200901316 | DOI Listing |
J Org Chem
January 2025
State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000 Gansu, P. R. China.
The asymmetric total syntheses of sarglamides A, C, and E in concise and protecting group free fashion is disclosed. Key steps involve an -selective Diels-Alder reaction to construct the bicyclo[2.2.
View Article and Find Full Text PDFNanoscale Adv
December 2024
Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle, Nanchang Hangkong University Nanchang 330063 P. R. China.
Photocatalytic reduction of CO to produce organic fuels is a promising strategy for addressing carbon reduction and energy scarcity. Transition metal carbides (TiCT ) are of particular interest due to their unique layered structures and excellent electrical conductivity. However, the practical application of TiCT is limited by the poor separation efficiency of photogenerated charge carriers and the low migration ability of photogenerated electrons.
View Article and Find Full Text PDFAm Surg
January 2025
Department of Surgery, Division of Acute Care Surgery and Surgical Critical Care, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
Fungal growth is common in intraoperative cultures of patients with perforated peptic ulcer (PPU) leading to the common use of empiric antifungal therapy, with current evidence not clearly supporting this practice. The goal of this updated systematic review and meta-analysis was to synthesize the effect of empiric antifungals in patients with PPU. Eligible studies were identified through a comprehensive literature search in the MEDLINE (PubMed) and EMBASE databases, following the PRISMA 2020 statement.
View Article and Find Full Text PDFBMC Nurs
January 2025
Nursing Department, School of Medicine, Shanghai Tenth People's Hospital, Tongji University, Shanghai, 200072, China.
Objective: A growing body of research shows that the organizational silence among nurses not only affects their job satisfaction and performance but also exacerbates their intention to leave their jobs, posing a threat to the long-term stability of the nursing team. Therefore, the aim of this study was to synthesize existing qualitative research to explore the real experiences of nurses' organizational silence behavior and gain insight into the motivations and feelings behind it.
Design: A qualitative review.
Study Design: Systematic scoping review.
Objectives: Extended reality (XR) is becoming a recognisable tool for assisting in spinal cord injury (SCI) rehabilitation. While the success of XR mediated interventions is often evaluated based on improvements in physical and functional performance, the present systematic scoping review aimed to identify and synthesize evidence on reported psychological outcomes of XR interventions in SCI rehabilitation.
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