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Keywords: chiral phosphoric acid; organocatalysis; cycloaddition; alkenes; alkynes EN chiral phosphoric acid organocatalysis cycloaddition alkenes alkynes 1200 1214 15 06/19/23 20230704 NES 230704 1 Introduction Asymmetric cycloaddition reaction is the most powerful strategy for the construction of various enantioenriched carbocycles and heterocycles, [1] because it provides an efficient and completely atom-economical route from simple precursors. In order to achieve this goal, we needed to overcome the following issues: (1) realization of efficient cycloaddition of alkynes with appropriate partners; (2) the installation of suitable groups onto alkynes to avoid free rotation around the potential C-C axes; (3) the choice of a competent chiral catalyst to promote the designed cycloaddition reactions and to control the stereoselectivity. 3 CPA-Catalyzed Cycloaddition of Alkynes Although the CPA-catalyzed cycloaddition of alkenes have been well documented, the CPA-catalyzed asymmetric cycloaddition reaction of alkynes is still lacking. On the other hand, the cycloaddition of alkynylnaphthols with imines proceeded via a sequential [4+2] cycloaddition, an alkyne-type Povarov cycloaddition, and an auto-oxidation reaction. [Extracted from the article]

Synthesis of bicyclic scaffolds has gained significant attention in drug discovery due to their potential to mimic benzene bioisosteres. Here, we present a mild and scalable Sc(OTf) 3 -catalyzed [3+2] cycloaddition of bicyclo[1.1.0]butanes (BCBs) with ynamides, yielding a diverse array of polysubstituted 2-amino-bicyclo[2.1.1]hexenes in good to excellent yields. These products offer valuable starting materials for the construction of novel functionalized bicyclo[1.1.0]butanes. Preliminary mechanistic studies indicate that the reaction involves a nucleophilic addition of ynamides to bicyclo[1.1.0]butanes, followed by an intramolecular cyclization of in situ generated enolate and keteniminium ion. We expect that these findings will encourage utilization of complex bioisosteres and foster further investigation into BCB-based cycloaddition chemistry., (© 2024 Wiley-VCH GmbH.)

Background: The Chinese government has proposed cancer screening guidelines and launched 2 cancer screening programs to improve screening practices. However, the screening participation rates of Chinese women remain low. Exploring the factors affecting breast cancer screening to promote cancer screening is necessary., Objective: The aim of this study was to investigate women's satisfaction with healthcare providers and screening practices., Methods: A cross-sectional survey was conducted from November 2019 to April 2020 in Changchun, Jilin Province, China. The Medical Care Satisfaction Scale and SERVQUAL were used to quantify women's satisfaction with doctors and nurses, respectively., Results: Women's satisfaction with doctors (68.81 ± 11.08; range, 20-100) and with nurses (87.64 ± 16.17; range, 22-110) was moderate. Compared with women who had not participated in screening within the past 2 years, screened women reported higher satisfaction with doctors (P = .026) and nurses (P = .012). Older age (P = .004) was an independent predictor of women's satisfaction with doctors. Similarly, women's education level (P = .049), chronic disease history (P = .029), and physical examination history (P = .039) were 3 independent predictors of women's satisfaction with nurses., Conclusions: Future intervention strategies can not only increase the screening rates by providing existing intervention methods but also improve women's satisfaction with healthcare providers to promote screening practices., Implications for Practice: This article provides a theoretical basis for healthcare providers to increase female screening practices. It also provides references for improving existing intervention methods., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)