Asymmetric synthesis of chiral pyrazolo[3,4-b]pyridin-6-ones under carbene catalysis.

A structurally diverse set of chiral pyrazolo[3,4-b]pyridin-6-ones was efficiently prepared in excellent yields with excellent enantioselectivities via N-heterocyclic carbene-catalyzed oxidative [3 + 3] annulation of enals with pyrazol-5-amines. The reaction features mild reaction conditions, a broad substrate scope, and easy scale-up.

Bifunctional squaramide catalyzed asymmetric synthesis of chiral α-mercaptosilanes.

Bifunctional squaramide-catalyzed nucleophilic addition of thiophenols to easily available ß-silyl α,ß-unsaturated carbonyl compounds has been successfully developed. A structurally diverse set of chiral α-mercaptosilanes was efficiently prepared in good to excellent yields with acceptable enantioselectivities. The reaction features mild reaction conditions, a broad substrate scope, and easy scale-up.

Shared decision-making and its influencing factors among parents of children with cancer in China: A cross-sectional study.

PURPOSE: This study aimed at exploring SDM implementation and its influencing factors, and preferences towards SDM among parents of children with cancer in China. DESIGN AND METHODS: This cross-sectional study recruited 204 participants from 2 grade-A tertiary hospitals in Guangzhou, China. The preferences towards decision-making, the status of SDM were measured by CPS-P and SDM-Q-9. The nurse support were measure by NPST, the needs of parents were measured by Questionnaire for Needs of Parents Whose Children are in PICU, and sociodemographic and disease-related questionnaires were used to investigate general information of children and parents. Descriptive statistics, univariate analysis, and multivariable linear regression were used for data analysis. RESULTS: Of 204 participants, about half of parents (55.4 %) tended to choose SDM, however, 40.2 % of them still show passive attitudes. The mean SDM-Q-9 score was 31.07 ± 8.74, and the result showed that age (ß = 2.480, P＜0.05), relapse (ß = 4.407, P＜0.01), course of disease (ß = -5.213, P＜0.01), relationships with doctors (ß = -4.05, P＜0.05), trust in doctors (ß = -2.796, P＜0.05), and communication and information support from nurses (ß = 0.651, P＜0.01) were the main factors influencing SDM for parents. CONCLUSIONS: Over half of Chinese parents tended to choose SDM, but their real participation in SDM is unsatisfactory. Parents who were older, had good relationships with doctors, trusted in doctors, received more communication and information support from nurses, and whose children had shorter course of disease, suffered relapses, participated in SDM better.

Research of deformation law about guide rails under the action of mining deformation in mine vertical shaft.

To lay a foundation for alleviating the influence of mining shaft deformation (MSD) on the guide rail (GR) and monitoring the shaft deformation state, this paper studies the deformation law and mechanism of the guide rail under the MSD. Firstly, a spring is used to simplify the interaction between the shaft lining and surrounding rock soil mass (SRSM) under MSD, and its stiffness coefficient is deduced by the elastic subgrade reaction method. Secondly, a simplified finite element model is established based on spring element, the stiffness coefficient is calculated by the derivation formula, and its effectiveness is verified. Finally, the deformation law and mechanism of GR are analyzed under different types and degrees of MSD, and the deformation characteristics are studied under the disconnection between the shaft, bunton and guide rail. The results show that the established finite element model can better simulate the interaction between the shaft lining and SRSM, and the calculation efficiency is greatly improved. The guide rail deformation (GRD) has a strong ability to characterize MSD and owns the distinctive feature corresponding to different types and degrees of MSD and the connection state. This research can provide reference and guidance for the shaft deformation monitoring and the maintenance and installation of the GR, and also lays a groundwork for studying operation characteristic of hoisting conveyance under MSD.

Desymmetrization of N-Cbz glutarimides through N-heterocyclic carbene organocatalysis.

Over the past decade, the catalysis of N-heterocyclic carbenes has achieved significant advances. In this area, aldehydes, enals, and esters, are commonly employed as starting materials through various catalytic activation modes. However, NHC-activated strategy of amide and its derivatives remains elusive. Described herein is the realization of asymmetric desymmetrization of N-Cbz glutarimides with alcohols through an imide C-N bond cleavage under NHC organocatalysis. A structurally diverse set of enantioenriched 4-amido esters is generated with acceptable yields and high enantioselectivities. This method features mild reaction conditions, excellent substrate scope, and excellent atom economy. DFT calculations have been performed to explore the detailed reaction mechanism and the origin of the enantioselectivity, which indicate that the strength of the C-H···O hydrogen bond and C-H⋯π interactions should be responsible for the stereoselectivity. The current strategy could open a door for efficient construction of (R)-Rolipram with excellent stereoselectivity.