A series of N-methylated polyarylurea oligomers have been reduced with potassium metal in HMPA. These reductions result in the transient formation of arylurea anion radicals, which undergo reductive elimination of the urea linkages. The aryl moieties appear in the products as the anion radicals of oligoaryl systems. The reaction is intramolecular, and the sequencing in the polyaryl anion radical remains the same as in the polyarylureas due to the urea-enforced pi-pi stacking interactions.
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http://dx.doi.org/10.1021/ol0496069 | DOI Listing |
F1000Res
January 2025
Postgraduate School of Universitas Brawijaya, Universitas Brawijaya, Malang, East Java, 65145, Indonesia.
Background: , known as the red pidada, has been widely utilized by the Indonesian. leaves contain various active compounds, contributing to their popularity in the treatment of various diseases. Mangrove leaves are also known to exhibit very high antioxidant activity.
View Article and Find Full Text PDFFood Res Int
February 2025
Department of Chemistry and Chemical Engineering, State Key Laboratory of Efficient Production of Forest Resources, Engineering Research Center of Forestry Biomass Materials and Bioenergy (Ministry of Education), Beijing Forestry University, Beijing 100083, China. Electronic address:
Galactomannan comes from a wide range of plant resources and has some biological activities, but its bioavailability is limited due to its large molecular weight and complex structure. In this study, three degradation methods (HO, ultrasound, and β-mannanase) combined with ethanol fractional precipitation (25 %, 50 %, and 75 %) were used to degrade and separate Gleditsia sinensis galactomannans (GSG), and the physicochemical properties and biological activities of GSG after degradation were analyzed. Comprehensive comparison indicates that HO exhibits had a better degradation effect.
View Article and Find Full Text PDFJ Pharm Biomed Anal
January 2025
Department of Bioscience and Technology for Food, Agriculture and Environmental, University of Teramo, Via Renato Balzarini 1, Teramo 64100, Italy. Electronic address:
Oxidative stress (OS) arises mainly from exposure to reactive oxygen species (ROS) such as superoxide anion, hydroxyl radical, and hydrogen peroxide. These molecules can cause significant damage to proteins, DNA, and lipids, leading to various diseases. Cells fight ROS with detoxifying enzymes; however, an imbalance can cause damage leading to ischemic conditions, heart disease progression, and neurological disorders such as Alzheimer's disease.
View Article and Find Full Text PDFWater Res
January 2025
Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305, USA. Electronic address:
Dry wells are neighborhood-scale stormwater infiltration systems increasingly used in drought-prone areas for stormwater capture and groundwater recharge. These systems bypass the low permeability surface soil to maximize infiltration rates. However, hydrophilic contaminants of emerging concern (CECs) in urban runoff pose potential groundwater contamination risks.
View Article and Find Full Text PDFPLoS One
January 2025
Department of Crop and Soil Sciences, College of Agricultural and Environmental Sciences, University of Georgia, Griffin, Georgia, United States of America.
Previous studies have indicated the great performance of electrooxidation (EO) to mineralize per- and polyfluoroalkyl substances (PFASs) in water, but different anions presented in wastewater may affect the implementation of EO treatment in field applications. This study invetigated EO treatment of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), two representative perfluoroalkyl acids (PFAAs), using porous Magnéli phase titanium suboxide anodes in electrolyte solutions with different anions present, including NO3-, SO42-, CO32- and PO43-. The experiment results indicate that CO32- enhanced PFAS degradation, while NO3- suppressed the degradation reactions with its concentration higher than 10 mM.
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