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1.
J Org Chem ; 88(16): 11728-11734, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37506052

RESUMEN

In this study, we present a novel, efficient method for the oxidative amination of sulfenamides using diacetoxyiodobenzene (PhI(OAc)2) and amines under basic conditions. This innovative technique streamlines the synthesis of sulfinamidines under mild, metal-free conditions, achieving outstanding yields of up to 99%. Furthermore, we propose possible pathways that elucidate the observed molecular sequence of events in this reaction. This cutting-edge approach not only advances the synthesis of valuable sulfinamidine compounds but also expands the synthetic toolbox available to chemists, paving the way for future discoveries in organic synthesis and potential applications in medicinal chemistry.

2.
Front Chem ; 11: 1179948, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37188095

RESUMEN

During the past decades, rheumatoid arthritis had become a serious problem, torturing millions of patients because of unclear pathogenesis and no ideal therapies. Natural products remain an important source of medicines to treat various major diseases such as rheumatoid arthritis (RA) given their excellent biocompatibility and structural diversity. Herein, we have developed a versatile synthetic method for constructing various skeletons of akuammiline alkaloid analogs based on our previous research on the total synthesis of the related indole alkaloids. We have also evaluated the effect of these analogs on the proliferation of RA fibroblast-like synoviocytes (FLSs) in vitro and analyzed the corresponding structure-activity relationship (SAR). Among these analogs, compounds 9 and 17c have demonstrated a promising inhibitory effect on the proliferation of RA-FLSs, with IC50 values of 3.22 ± 0.29 µM and 3.21 ± 0.31 µM, respectively. Our findings provide a solid foundation for future pharmacological studies on akuammiline alkaloid derivatives and inspiration for the development of anti-RA small molecule drugs derived from natural products.

3.
Org Lett ; 25(12): 2151-2156, 2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-36946517

RESUMEN

In this study, we present a novel and efficient approach for the oxidative esterification of sulfenamides using phenyliodonium diacetate, enabling the synthesis of sulfinimidate esters and sulfilimines under mild and metal-free conditions, with yields reaching up to 99%. The protocol is readily scalable and compatible with a diverse range of substrates and functional groups, and we demonstrate its potential for late-stage functionalization of pharmacologically relevant molecules. Furthermore, we propose a plausible reaction mechanism to account for the observed sequence of events.

4.
Environ Sci Pollut Res Int ; 30(12): 32722-32736, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36469264

RESUMEN

Most of the developed countries across the globe have targeted to attain sustainable economic growth. With this focus, the current study evaluated 29 OECD countries over the time period of 1990 to 2018 to analyze the influence of economic and environmental indicators, i.e., export diversification, institutional quality, macrocosmic variables on carbon dioxide, and greenhouse gas emissions. The current study used the quantile regression and generalized method of moments approach on the selected panel. Our comprehensive econometric approach allows us to reveal that export diversification negatively affects carbon emissions but promotes greenhouse gas emissions. Similarly, institutional quality, economic growth, financial development, and economic growth helps to reduce carbon emissions but increase greenhouse emissions. In comparison, trade openness exhibits a positive influence on carbon emissions but a negative on greenhouse gas emissions. Besides, urbanization is found one of the major reasons for environmental degradation. In light of empirical fact findings, this study commends some innovative policy insights for scholars, governors, and policymakers.


Asunto(s)
Gases de Efecto Invernadero , Gases de Efecto Invernadero/análisis , Organización para la Cooperación y el Desarrollo Económico , Desarrollo Económico , Dióxido de Carbono/análisis , Políticas
5.
Environ Sci Pollut Res Int ; 30(8): 21769-21780, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36274074

RESUMEN

Climate change and global warming have been driven by a rise in carbon dioxide (CO2) concentrations in recent decades, posing a danger to environmental sustainability. Thus, this research scrutinizes the effects of two types of energy (coal and geothermal) and natural resources on CO2 emissions in 10 newly industrialized countries (NICs). The study also considers the role of financial globalization using a data between 1990 and 2019. This research applied a fresh nonparametric econometric technique termed "method of moments quantile regression (MMQR)." This approach is resistant to outliers and produces an asymmetric connection between variables. Furthermore, the long-run estimators (AMG and CCEMG) are employed as a robustness check. The findings reveal that natural resources, coal, and economic growth contribute to the degradation of the environment in the NICs in all quantiles (0.1-0.90). However, geothermal energy aids in enhancing environmental sustainability at all quantile distributions (0.1-0.90). Our findings are robust with alternative methods (AMG and CCEMG). The research's outcomes have the potential to help NICs nations design policies. Finally, based on the research results, a policy framework is proposed to solve the objectives of SDGs 7 and 13.


Asunto(s)
Energía Geotérmica , Desarrollo Sostenible , Dióxido de Carbono/análisis , Recursos Naturales , Desarrollo Económico , Carbón Mineral , Energía Renovable
6.
Org Biomol Chem ; 20(46): 9228-9233, 2022 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-36382352

RESUMEN

The construction of the 3-allyl/3-allenyl-3-(thio)oxindole core remains a challenge in organic synthesis. Herein, we report a novel Rh2(esp)2 catalytic Doyle-Kirmse reaction to furnish the oxindole core, bearing unbiased NH as well as a quaternary stereogenic center at the 3-position, in good to excellent yields under mild conditions. These reactions are concise, practical, atom-economic, and highly efficient, and feature a TON of up to 3700. Moreover, a non-radical pathway was observed in this approach.


Asunto(s)
Indoles , Oxindoles , Estereoisomerismo , Estructura Molecular , Catálisis
7.
Environ Sci Pollut Res Int ; 28(41): 58241-58257, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34110589

RESUMEN

This study aims to provide a comprehensive knowledge map of tourism and environmental degradation literature review based on scientific articles published between 1999 and 2020. The study provides an overview of research, influential authors, and journals. The PR China has maintained the lead in academic research with the most contribution in academic research in recent years. Sustainability, the Chinese Academy of Sciences, and Katircioglu are the most productive journal, academic institution, and author in the field of tourism and environmental degradation, respectively. The degree of research contribution among researchers, institutional and national level, has an upward trend in recent years, but the research contribution among author level is higher than the institutional and national level. Furthermore, co-citation analysis suggests that research articles in the field are closely related. "Investigating the influence of tourism on economic growth and carbon emissions: Evidence from panel analysis of the European Union" authored by Lee is the most cited article. Our analysis of abstracts and keywords shows that climate change, ecotourism, carbon emissions, economic growth, and energy consumption are the hot spots of academic literature. We suggest that research collaboration between developed and developing nations should be promoted in creating sustainable tourism reforms.


Asunto(s)
Bibliometría , Turismo , China , Desarrollo Económico , Publicaciones
8.
Environ Sci Pollut Res Int ; 28(28): 37016-37030, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34050514

RESUMEN

AbstractThe aim of the "One Belt and One Road" (OBOR) project proposed by China is to encourage extension of global value chains, facilitate regional integration and increase efficient resource allocation. In recent times, scientific literature has examined the investment decisions of the OBOR investment and how it will affect the governmental policies, environmental initiatives, and bilateral flow of economic resources. Current study, based on Web of Science database, uses bibliometric methodology to map the research trends in OBOR publications. We contribute in the economic literature in the associated fields of OBOR publications in the following ways: (1) identify the most influential researchers, articles, and academic institutions, (2) mapping the interdisciplinary character of OBOR investments and its bibliometric similarity to adjacent fields, (3) visualize nature and trends of the research field, and (4) synthesizing future research areas. Although OBOR initiative has received considerable traction, but to this date, there is no bibliometric study on this topic. The findings of current study will help policymakers and academics to navigate the OBOR literature, provide a systematic basis for developing the field, and suggest promising future research avenues.


Asunto(s)
Bibliometría , Publicaciones , China , Bases de Datos Factuales , Inversiones en Salud
9.
Artículo en Inglés | MEDLINE | ID: mdl-33634403

RESUMEN

In the current context of the COVID-19 pandemic, researchers are working with health professionals to inform governments on how to formulate health strategies. In this study, we examine the correlation between environmental and climate indicators and COVID-19 outbreak in the top 10 most affected states of the USA. In doing so, PM2.5, temperature, humidity, environmental quality index, and rainfall are included as crucial meteorological and environmental factors. Kendall and Spearman rank correlation coefficients, quantile regression, and log-linear negative binominal analysis are employed as an estimation strategy. The empirical estimates conclude that temperature, humidity, environmental quality index, PM2.5, and rainfall are significant factors related to the COVID-19 pandemic in the top 10 most affected states of the USA. The empirical findings of the current study would serve as key policy input to mitigate the rapid spread of COVID-19 across the USA.

10.
Environ Sci Pollut Res Int ; 28(14): 16982-16999, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33641097

RESUMEN

This study aims to provide a detailed overview of environmental Kuznets curve hypothesis using bibliometric analysis for the Web of Science (WOS) database. Our analysis provides an overview of research trends, journals and most influential authors. China has contributed the most scientific publications; followed by the USA, Turkey, and Pakistan. Muhammad Shahbaz, Beijing Institute of Technology, and Environmental Science and Pollution Research are the most productive author, research institute, and research journal in EKC publications. Trend analysis of researchers, academic and country-level, reveal that publications in the environmental Kuznets curve have upward trend; also, cocitation analysis indicates that EKC publications are closely related. "Economic growth and income inequality" (1955) by Simon Kuznets is considered to be the basic literature, and "environmental Kuznets curve hypothesis: A Survey" by Dinda (2004) is the most cited research article in the literature. Keywords and abstracts analysis further reveals that carbon emissions, renewable energy, energy consumption, economic growth, and sustainable development are the hot topics in current literature. We propose that joint research projects between industrial and emerging economies will promote research activities.


Asunto(s)
Dióxido de Carbono , Desarrollo Económico , Beijing , Dióxido de Carbono/análisis , China , Contaminación Ambiental/análisis , Pakistán , Energía Renovable , Turquía
11.
Risk Manag Healthc Policy ; 14: 67-74, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33447110

RESUMEN

INTRODUCTION: In the current context of the COVID-19 pandemic, researchers are working with health professionals to inform governments to slow the virus's spread. The extant research contribution has been dedicated to examining the impact of climate indicators such as temperature, humidity, and rainfall. However, there is a lack of evidence regarding their combined association between environmental quality and climate indicators to combat COVID-19 in the South American context. METHODS: In this study, we collected data for environmental pollution indicators for the South America region, and correlation analysis and wavelet transform coherence were used as the analytical tools. RESULTS: Empirical estimates conclude that PM10, NO2, CO, and O3 are significant factors in the fight against the COVID-19 pandemic in South America. IMPLICATIONS: Our findings will serve as policy implications for the state, health officials, and regulators to combat the COVID-19 pandemic outbreak in South America.

12.
Environ Sci Pollut Res Int ; 28(16): 20700-20716, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33405155

RESUMEN

This study aims to provide a systematic literature review based on bibliometric analysis for scientific articles published between 1999 and 2019 extracted from Clarivate Analytics' Web of Science (WOS) database. The current research project provides an overview of scientific publications, influential authors, and research journals. Our analysis reveals that the USA leads the academic research contribution, whereas China has provided the most research publications in recent years. Environmental and Resource Economics, University of London, and Barcena-Ruiz are the most productive journal, academic institution, and author in the field of environmental taxes, respectively. The degree of research contribution among researchers, institutional and national level, has an upward trend in recent years; however, the research contribution at the author level is higher than the institutional and national level. Furthermore, cocitation analysis suggests that research articles in the dataset are closely related. Pigou's "The economics of welfare" published in 1920, is considered as the basic literature, and the "In defence of degrowth" authored by Giorgis Kallis is the most cited article. Our analysis of abstracts and keywords indicates that climate change, environmental taxes, double dividend, carbon tax, and environmental pollution are the hotspots within academic literature. We suggest that research collaboration between developed and developing nations and further coordination among environmental agencies such as IEA and IPCC will enhance the effectiveness of environmental reforms.


Asunto(s)
Bibliometría , Publicaciones , China , Contaminación Ambiental , Impuestos
13.
Org Lett ; 22(17): 6911-6916, 2020 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-32830501

RESUMEN

Herein, we present a hemin-catalyzed oxidative phenol-hydrazone [3+3] cycloaddition that accommodates a broad spectrum of N-arylhydrazones, a class of less exploited 1,3-dipoles due to their significant Lewis basicity and weak tendency to undergo 1,2-prototropy to form azomethine imines. It renders expedient assembly of diversely functionalized 1,3,4-oxadiazines with excellent atom and step economy. Preliminary mechanistic studies point to the involvement of a one-electron oxidation pathway, which likely differs from the base-promoted aerobic oxidative scenario.

14.
Air Qual Atmos Health ; 13(11): 1385-1394, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32837621

RESUMEN

The impact of environmental pollutants and climate indicators on the outbreak of COVID-19 has gained considerable attention in the recent literature. However, specific investigation of industrial economies like Germany is not available. This provides us motivation to examine the association between environmental pollutants, climate indicators and the COVID-19 cases, recoveries, and deaths in Germany using daily data from February 24, 2020, to July 02, 2020. The correlation analysis and wavelet transform coherence (WTC) approach are the analytical tools, which are used to explore the association between variables included in the study. Our findings indicate that PM2.5, O3, and NO2 have a significant relationship with the outbreak of COVID-19. In addition, temperature is the only significant climate indicator which has significant correlation with the spread of COVID-19. Finally, PM10, humidity, and environmental quality index have a significant relationship only with the active cases from COVID-19 pandemic. Our findings conclude that Germany's successful response to COVID-19 is attributed to environmental legislation and the medical care system, which oversaw significant overhaul after the SARS and MERS outbreaks. The current study implicates that other industrial economies, especially European economies, that are still facing COVID-19 outbreak can follow the German model for pandemic response.

15.
Environ Res ; 187: 109652, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32405084

RESUMEN

In December 2019, the novel coronavirus COVID-19 outbreak was first detected in Wuhan Hubei province, China. The April 24, 2020, the Centers for Disease Control and Preventions (CDC) has confirmed more than 39,000 cases, including >1800 deaths. California's Governor Gavin Newsom ordered mandatory stay at home after World Health Organization (WHO) declared COVID-19 as a global pandemic in early March. We have evaluated the correlation between environmental pollution determinants and the COVID-19 outbreak in California by using the secondary published data from the Centers for Disease Control and the Environmental Pollution Agency (EPA). We employed Spearman and Kendall correlation tests to analyze the association of PM 2.5, PM 10, SO2, NO2, Pb, VOC, and CO with COVID-19 cases in California. Our findings indicate that environmental pollutants such as PM10, PM2.5, SO2, NO2, and CO have a significant correlation with the COVID-19 epidemic in California. Overall, our study is a useful supplement to encourage regulatory bodies to promote changes in environmental policies as pollution source control can reduce the harmful effects of environmental pollutants.


Asunto(s)
Contaminación del Aire/efectos adversos , Infecciones por Coronavirus/epidemiología , Neumonía Viral/epidemiología , Betacoronavirus , COVID-19 , California/epidemiología , Humanos , Pandemias , Material Particulado/efectos adversos , SARS-CoV-2
16.
Chem Commun (Camb) ; 56(44): 5965-5968, 2020 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-32347248

RESUMEN

Reported herein is the first catalytic oxidative [4+2] cycloaddition of 2-aminophenols with cyclic enamines. This biomimetic catalytic oxidative strategy expediently accommodates the very labile structurally unbiased ortho-quinone monoimine intermediate for cycloaddition by controlling its formation rate, thus refraining from otherwise prerequisite steric or electronic stabilization and allowing efficient assembly of various tricyclic 1,4-benzoxazines in a step and atom economic fashion.

17.
Sci Total Environ ; 728: 138835, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32334162

RESUMEN

This study analyzed the association between COVID-19 and climate indicators in New York City, USA. We used secondary published data from New York city health services and National weather service, USA. The climate indicators included in the study are average temperature, minimum temperature, maximum temperature, rainfall, average humidity, wind speed, and air quality. Kendall and Spearman rank correlation tests were chosen for data analysis. We find that average temperature, minimum temperature, and air quality were significantly associated with the COVID-19 pandemic. The findings of this study will help World Health Organization and health regulators such as Center for Disease Control (CDC) to combat COVID-19 in New York and the rest of the world.


Asunto(s)
Clima , Infecciones por Coronavirus/epidemiología , Neumonía Viral/epidemiología , Contaminación del Aire , Betacoronavirus , COVID-19 , Humanos , Humedad , Ciudad de Nueva York/epidemiología , Pandemias , SARS-CoV-2 , Temperatura , Viento
18.
Drug Dev Res ; 80(5): 595-605, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30964563

RESUMEN

Novel bioactive compounds as synthetic analogs of the potent herbal medicines can be optimized as potential drug candidates for various neurologic disorders. This study was performed to investigate the newly synthesized dibenzylidene ketone derivatives: (2E,6E)-2,6-dibenzylidene cyclohexanone (A1K1) and (1E,4E)-5-(2,3-dichlorophenyl)-1-(4-methoxyphenyl)-2-methylpenta-1,4-diene-3-one (A2K2) and evaluate its potential anti-Alzheimer's and anti-depressant properties. Both the derivatives are chemically characterized by using HNMR and CNMR techniques. Auto Dock Vina program was used to investigate ligand-protein affinity. Forced swim test, tail suspension test, open field test, Y-maze test, and Morris water maze test (MWM) models were employed to evaluate anti-depressant and anti-Alzheimer's activity of dibenzylidene ketone derivatives in mice. Both A1K1 and A2K2 showed high binding affinities against various proteins involved in depression and Alzheimer's mechanisms like monoamine oxidase B, acetylcholinesterase, norepinephrine transporter 2, serotonin transporter, dopamine receptor, serotonin receptor modulator, and beta-amyloid targets. A1K1 and A2K2 dose-dependently (0.1-1 mg/kg) decreased immobility time, while increased swimming and climbing time of mice in forced swim test (FST). A1K1 and A2K2 decreased animal immobility time in TST. In the open field test, both A1K1 and A2K2 increased the number of ambulations and rearings. A1K1 and A2K2 dose-dependently (0.5-1.0 mg/kg) increased spontaneous alternation behavior (%) and the number of entries of mice in Y-maze test. In the MWM test, A1K1 and A2K2 decreased escape latency time. Overall, both in-silico and in-vivo investigations of A1K1 and A2K2, report their therapeutic potential for antidepressant and anti-Alzheimer properties. Hence, these compounds possess potent neuroprotective properties and may be further evaluated for their therapeutic potential in various neurological disorders.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Antidepresivos/síntesis química , Conducta Animal/efectos de los fármacos , Biomarcadores/metabolismo , Depresión/metabolismo , Pentanonas/síntesis química , Enfermedad de Alzheimer/tratamiento farmacológico , Animales , Antidepresivos/administración & dosificación , Antidepresivos/química , Antidepresivos/farmacología , Biomarcadores/química , Depresión/tratamiento farmacológico , Relación Dosis-Respuesta a Droga , Femenino , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Modelos Moleculares , Simulación del Acoplamiento Molecular , Pentanonas/administración & dosificación , Pentanonas/química , Pentanonas/farmacología
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