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The synthesis of chiral α-azaheteroaryl oxiranes via enantioselective catalysis is a formidable challenge due to the required complex stereoselectivity and diverse N-heterocyclic structures. These compounds play a crucial role in developing bioactive molecules, where precise chirality significantly influences biological activity. Here we show that using chiral phosphoric acid as a catalyst, our method efficiently addresses these challenges. This technique not only achieves high enantio- and diastereoselectivity but also demonstrates superior chemo- and stereocontrol during the epoxidation of alkenyl aza-heteroarenes. Our approach leverages a synergistic blend of electrostatic and hydrogen-bonding interactions, enabling the effective activation of both substrates and hydrogen peroxide. The resulting chiral oxiranes exhibit enhanced diversity and functionality, aiding the construction of complex chiral azaaryl compounds with contiguous stereocenters. Kinetic and density functional theory studies elucidate the mechanism, highlighting chiral phosphoric acid's pivotal role in this intricate enantioselective process. Chiral azaarenes hold critical importance in pharmaceutical research due to their significant impact on drug efficacy and selectivity. Herein, the authors report the synthesis of chiral α-azaheteroaryl oxiranes via catalytic enantioselective epoxidation of alkenyl aza-heteroarenes using chiral phosphoric acid and hydrogen peroxide. [ABSTRACT FROM AUTHOR]

Objective To analyze the influencing factors and improvement paths of the service capacity of standardized township health centers in Guangxi under the background of "high-quality service at the grassroots level", providing useful reference for further deepening reform and promoting the healthy development of rural medical and health systems. Methods By the end of 2021, township health centers that have reached the recommended standard of "quality service primary line" service ability were selected as the research samples, and the coupled coordination degree model was combined with fuzzy set qualitative comparative analysis method to carry out empirical analysis. Results Single factors cannot constitute a necessary condition for improving or decreasing the service capacity of township health centers. There are a total of four configuration paths for improving the service capacity of township health centers in Guangxi, among which the core sufficient conditions for playing a leading role are the number of high-level practicing (assistant) physicians, the number of registered nurses, and coupling coordination scheduling. The overall consistency of the solution is 0.920 (≥0.8), and the model has strong explanatory power. Conclusion The improvement of service capacity in township health centers in Guangxi is facilitated by the synergistic effect of multiple factors both internally and externally. The optimization and expansion of grassroots talent teams is the core combination element for the improvement of service capacity in township health centers, and the coupling and coordinated development of medical resource allocation and economy is the key element for the improvement of service capacity. [ABSTRACT FROM AUTHOR]

Twenty-one compounds were isolated and elucidated from the roots of Rhodiola rosea L. , including two new compounds (1–2), along with nineteen known compounds (3 - 21), compounds 4 , 5 , 7 , 8 , 13 , 17 , 21 were isolated for the first time from Plants of the Sedum family and compounds 14 , 20 were separated for the first time from the genus Sedum. In the present study, the structures of the compounds were investigated by NMR spectroscopy by comparing the data with those reported in the literature. Moreover, all isolates were tested for their neuroprotective activities aga BV NM. C, inst CoCl 2 -induced injury in PC12 cells. As a result, compound 7 showed better neuroprotective effects with cell viability (56.56 ± 1.2)% at 20 μ M. [Display omitted] • A new phenolic compound and an aliphatic chain compound were isolated from Rhodiola rosea L. • Seven compounds were isolated from Plants of the Sedum family for the first time. • Two compounds were isolated from the genus Sedum for the first time. • Compound 7 (Mallonanosid A) had better neuroprotective effects with cell viability of (56.56 ± 1.2) % at 20 μ M. [ABSTRACT FROM AUTHOR]

This correction notice is for an article titled "Chiral phosphoric acid-catalyzed asymmetric epoxidation of alkenyl aza-heteroarenes using hydrogen peroxide" published in Nature Communications. The correction addresses two errors in the original article. Firstly, there was a mistake in the CCDC number for compound 3ah in the Data availability statement, which has been corrected. Secondly, the original article omitted an acknowledgement for funding support, which has now been included. The correction has been made in both the PDF and HTML versions of the article. [Extracted from the article]