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1.
J Org Chem ; 89(13): 9352-9359, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38872240

RESUMEN

Saturated N-heterocycles are found in numerous bioactive natural products and are prevalent in pharmaceuticals and agrochemicals. While there are many methods for their synthesis, each has its limitations, such as scope and functional group tolerance. Herein, we describe a rhodium-catalyzed transfer hydrogenation of pyridinium salts to access N-(hetero)aryl piperidines. The reaction proceeds via a reductive transamination process, involving the initial formation of a dihydropyridine intermediate via reduction of the pyridinium ion with HCOOH, which is intercepted by water and then hydrolyzed. Subsequent reductive amination with an exogenous (hetero)aryl amine affords an N-(hetero)aryl piperidine. This reductive transamination method thus allows for access of N-(hetero)aryl piperidines from readily available pyridine derivatives, expanding the toolbox of dearomatization and skeletal editing.

2.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 55(3): 680-686, 2024 May 20.
Artículo en Zh | MEDLINE | ID: mdl-38948264

RESUMEN

Objective: To investigate the effect of empathy on depressive symptoms in adolescents and to explore the potential mediating role of family functioning in the effect of empathy on depressive symptoms. Methods: The 2022 cross-sectional data from the Chengdu Positive Child Development (CPCD) cohort were analyzed in the study. A survey was conducted in Chengdu in June 2022, involving 3020 students in grades 5-8 from three randomly selected stratified schools. The Interpersonal Reactivity Index (IRI-C), the Chinese Family Assessment Instrument (C-FAI), and the Center for Epidemiologic Studies Depression Scale for Children (CES-DC) were used in the survey. Chi-square test or one-way analysis of variance was performed to examine the differences in various demographic characteristics (sex, grade, region, and total monthly household income) between groups of respondents, as well as the differences in family functioning, empathy, and depression. Pearson correlation coefficient was used to examine the correlation between family functioning, empathy, and depressive symptoms. Structural equation modeling and SPSS PROCESS component Model 4 were used to analyze whether family functioning played a mediating role in the effect of empathy on depressive symptoms in adolescents. Results: The detection rate of depressive symptoms among survey respondents was 25.40%. The results of the difference analysis revealed significant differences in the detection rates of depressive symptoms among respondents of different grades, regions, and monthly household incomes (P<0.05). There was no significant difference in the detection rates of depressive symptoms between male and female students. There was a significant difference in the detection rate of depressive symptoms between respondents with different scores for family dysfunction and empathy ability (P<0.001). Correlation analysis results showed that empathy scores were negatively correlated with depression (r=-0.11, P<0.001), that family dysfunction was positively correlated with depression (r=0.29, P<0.001), and that empathy scores were negatively correlated with family functioning (r=-0.37, P<0.001). The mediating role of family dysfunction in the relationship between empathy and depressive symptoms was established, with the direct effect being 0.039 (95% confidence interval [CI]: 0.010-0.069, P<0.001) and the indirect effect value being -0.096 (95% CI: -0.115--0.079, P<0.001). The direct effect value accounted for 28.89% of the total effect value, while the mediation effect value accounted for 71.11% of the total effect value. Conclusion: The empathy ability of adolescents is correlated to depressive symptoms, and family functioning plays a mediating role between empathy and depressive symptoms in adolescents. It is suggested that adolescents' empathy ability and family functioning should be enhanced through multiple channels to reduce the occurrence of depressive symptoms.


Asunto(s)
Depresión , Empatía , Humanos , Adolescente , Depresión/psicología , Masculino , Femenino , Estudios Transversales , Encuestas y Cuestionarios , Relaciones Familiares/psicología , Estudiantes/psicología , China , Familia/psicología
3.
Angew Chem Int Ed Engl ; 63(6): e202314355, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-37914669

RESUMEN

Cheap, stable and easy-to-handle Werner ammine salts have been known for more than a century; but they have been rarely used in organic synthesis. Herein, we report that the Werner hexammine complex [Ni(NH3 )6 ]Cl2 can be used as both a nitrogen and a catalytic nickel source that allow for the efficient amination of aryl chlorides in the presence of a catalytic amount of bipyridine ligand under the irradiation of 390-395 nm light without the need of any additional catalysts. More than 80 aryl chlorides, including more than 20 drug molecules, were aminated, demonstrating the practicality and generality of this method in synthetic chemistry. A slow NH3 release mechanism is in operation, obviating the problem of catalyst poisoning. Still interestingly, we show that the Werner salt can be easily recovered and reused, solving the problem of difficult recovery of transition metal nickel catalysts. The protocol thus provides an efficient new strategy for the synthesis of primary aryl amines.

4.
Chemistry ; 29(37): e202300458, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37066524

RESUMEN

This paper reports a photochemical C-N coupling of abundant, but less reactive aryl chlorides, with structurally diverse primary and secondary amides by Ni-mediated without an external photocatalyst. Under the irradiation of light (390-395 nm) with a soluble organic amine as the base, the reaction allows for the successful transformation of (hetero)aryl chlorides to a wide range of N-aryl amides. More than 60 examples are shown, demonstrating the feasibility and applicability of this protocol in organic synthesis. Mechanic studies indicate that this amidation proceeds via a Ni(I)-Ni(III) catalytic cycle.

5.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(2): 374-379, 2023 Mar.
Artículo en Zh | MEDLINE | ID: mdl-36949701

RESUMEN

Objective: To study the current status of non-suicidal self-injury (NSSI) incidents among middle school students in Chengdu during the COVID-19 epidemic and to explore the mechanism of action of depression on the relationship between family environment and NSSI. Methods: Data were obtained from the Chengdu Positive Child Development (CDPD) cohort. In June and July 2020, after primary and secondary schools were reopened after the closure due to the COVID-19 epidemic, on-site questionnaire surveys were conducted with the Deliberate Self-Harm Inventory (DSHI), the Chinese Family Assessment Instrument (C-FAI), and Center for Epidemiologic Studies Depression Scale for Children (CES-DC), thereby obtaining the data of 3595 middle school students. Two-sample t-test and χ 2 test were used to compare the incidence of NSSI among middle school students of different grades and genders, and the Model 58 test of the SPSS PROCESS component was used to analyze the mediating effect of gender-mediated depression. Results: 1) The incidence of NSSI among middle school students in Chengdu during the COVID-19 epidemic was 49.67%. The incidence of NSSI among ninth-graders (80.70%) was significantly higher than those of the eighth graders (33.82%) and seventh graders (32.32%), and the incidence of NSSI among female middle school students (54.75%) was significantly higher than that of male students (44.52%). 2) Family environment ( r=0.34, P<0.001) and depression ( r=0.50, P<0.001) were positively correlated with NSSI. 3) Depression partially mediated the effect of family environment on NSSI, with the mediating effect accounting for 64.64% of the total effect. Compared with that of male students, the positive predictive effect between family environment and depression and that between depression and NSSI in female middle school students were more significant. Conclusion: During the COVID-19 pandemic, middle school students in Chengdu had a high incidence of NSSI, which indicates that the family environment should be improved, more attention should be given to gender differences, and early screening and intervention for depression should be strengthened to reduce the incidence of NSSI.


Asunto(s)
COVID-19 , Conducta Autodestructiva , Niño , Humanos , Masculino , Femenino , Depresión/epidemiología , Pandemias , Conducta Autodestructiva/epidemiología , COVID-19/epidemiología , Estudiantes , Factores de Riesgo
6.
J Org Chem ; 87(15): 10285-10297, 2022 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-35877165

RESUMEN

The Buchwald-Hartwig C-N coupling reaction has been ranked as one of the 20 most frequently used reactions in medicinal chemistry. Owing to its much lower cost and higher reactivity toward less reactive aryl chlorides than palladium, the C-N coupling reaction catalyzed by Ni-based catalysts has received a great deal of attention. However, there appear to be no universal, practical Ni catalytic systems so far that could enable the coupling of electron-rich and electron-poor aryl halides with both primary and secondary alkyl amines. In this study, it is reported that a Ni(II)-bipyridine complex catalyzes efficient C-N coupling of aryl chlorides and bromides with various primary and secondary alkyl amines under direct excitation with light. Intramolecular C-N coupling is also demonstrated. The feasibility and applicability of the protocol in organic synthesis is attested by more than 200 examples.

7.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(5): 866-871, 2022 Sep.
Artículo en Zh | MEDLINE | ID: mdl-36224690

RESUMEN

Objective: To examine the prevalence of suicide-related behaviors among junior middle school students, and to explore the mediating role of depression in the relationship between suicide-related behaviors and family function. Methods: A total of 2572 junior middle school students from three middle schools in Chengdu were interviewed face-to-face by using suicide-related items from Youth Risk Behavior Surveillance System (YRBSS), Chinese Family Assessment Instrument (C-FAI), and Center for Epidemiologic Studies Depression Scale for Children (CES-DC). The mediating role of depression was analyzed with structural equation model. Results: The prevalence of suicide-related behaviors was 26.01% among the respondents. The prevalence of suicide ideation, suicide plan and suicide attempt were 24.38%, 13.49% and 10.77%, respectively. Depression played a partial mediating role in how family function impacted on suicide-related behaviors, presenting a direct effect value of 0.170 (95% CI: 0.117-0.218, P<0.001) and an indirect effect value of 0.205 (95% CI: 0.176-0.234, P<0.001), with the mediating effect accounting for 54.67% of the total effect. Conclusion: Poor family function may increase the risk of suicide-related behaviors, and this effect is produced mostly through the impact on children's mental health. Improving family function will not only improve children's psychological status, but also reduce suicide-related behaviors.


Asunto(s)
Depresión , Asunción de Riesgos , Adolescente , Niño , Depresión/epidemiología , Humanos , Prevalencia , Factores de Riesgo , Instituciones Académicas , Estudiantes/psicología
8.
Angew Chem Int Ed Engl ; 60(39): 21536-21542, 2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34260129

RESUMEN

The Buchwald-Hartwig C-N coupling reaction has found widespread applications in organic synthesis. Over the past two decades or so, many improved catalysts have been introduced, allowing various amines and aryl electrophiles to be readily used nowadays. However, there lacks a protocol that could be used to couple a wide range of chiral amines and aryl halides, without erosion of the enantiomeric excess (ee). Reported in this article is a method based on molecular Ni catalysis driven by light, which enables stereoretentive C-N coupling of optically active amines, amino alcohols, and amino acid esters with aryl bromides, with no need for any external photosensitizer. The method is effective for a wide variety of coupling partners, including those bearing functional groups sensitive to bases and nucleophiles, thus providing a viable alternative to accessing synthetically important chiral N-aryl amines, amino alcohols, and amino acids esters. Its viability is demonstrated by 92 examples with up to 99 % ee.

9.
Org Lett ; 25(18): 3287-3292, 2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37114772

RESUMEN

A general and highly efficient photochemical C-N coupling reaction of challenging (hetero)aryl chlorides with hydrazides is reported. Catalyzed by a Ni(II)-bipyridine complex, this reaction provides an efficient tool for the synthesis of arylhydrazines in the presence of a soluble organic amine base without an external photosensitizer. The reaction features a wide substrate range (54 examples) and excellent functional group tolerance. The method has also been successfully applied to the three-step concise synthesis of rizatriptan, an effective drug for migraine and cluster headaches.

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