98%
921
2 minutes
20
A facile transition-metal-free protocol to form 2-iminoimidazo[1, 2-]-pyridines bearing a -CHBr group and an aza-quaternary carbon center at the 3 position from -(2-pyridyl)amidines substrates, in which the new heterocyclic skeletons constructed from amidines radical reactions or nucleophilic substitution reactions are promoted only by CBr under mild conditions, is demonstrated. The reactions were realized by intramolecular CDC reaction involving C-N and C-C bond formation the sequential C(sp)-H bifunctionalization mode on the same carbon atom under mild conditions. Moreover, this work also provides an excellent and representative example for CBr as an efficient reagent to initiate radical reactions under initiator-free conditions or to give rise to nucleophilic substitution reactions only by base.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9076575 | PMC |
http://dx.doi.org/10.1039/c9ra09265j | DOI Listing |
Acc Chem Res
September 2025
Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa, Ave. Ferrocarril San Rafael Atlixco 186, Col. Leyes de Reforma 1A sección, Alcaldía Iztapalapa, 09310 Mexico City, Mexico.
ConspectusWhat does the word antioxidant mean? Antioxidants are supposed to be nontoxic, versatile molecules capable of counteracting the damaging effects of oxidative stress (OS). Thus, when evaluating a candidate molecule as an antioxidant, several aspects should be considered. Antioxidants are more than free radical scavengers.
View Article and Find Full Text PDFChem Pharm Bull (Tokyo)
September 2025
Faculty of Pharmacy, Keio University, 1-5-30 Shibakoen, Minato-ku, Tokyo 105-8512, Japan.
Therapeutic drug monitoring (TDM) is vital for effective optimization of pharmacological treatments. In this study, we engineered a chromatography column that is sensitive to temperature fluctuations, thereby enabling safe and straightforward TDM without relying on organic solvents. Silica beads were modified by applying poly(N-isopropylacrylamide) (PNIPAAm) hydrogels, using a condensation reaction to modify the initiator, followed by radical polymerization to integrate the PNIPAAm hydrogel.
View Article and Find Full Text PDFInt J Biol Macromol
September 2025
College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, PR China. Electronic address:
As the primary storage protein, highland barley gliadin (HBG) exhibits limitations in the processing of highland barley foods, primarily due to its abundant non-polar amino acids. In this study, HBG was utilized to prepare sugar-HBG complexes with pentose (xylose), hexoses (glucose and galactose), and disaccharides (lactose and maltose) in an aqueous system at a pH of 11 and a temperature of 75 °C. Subsequently, the structural and functional characteristics of these complexes were evaluated.
View Article and Find Full Text PDFOrg Lett
September 2025
College of Materials and Chemical Engineering, Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials, China Three Gorges University, Yichang, Hubei 443002, P. R. China.
A novel copper-catalyzed radical cross-coupling reaction for the thioesterification of polyfluoroarenes is developed using KS and aldehydes in water. This protocol employs a readily available KS as a sulfur source, eliminating the need for hazardous thiols and organic solvents. The mild reaction conditions are compatible with a wide range of functional groups, providing access to diverse polyfluoroaryl thioesters.
View Article and Find Full Text PDFOrg Biomol Chem
September 2025
Research Centre of Modern Analytical Technology, Tianjin University of Science & Technology, Tianjin 300457, China.
A tetrahydroxydiboron-mediated radical cyclization of unactivated alkenes under photoinduced reaction conditions was developed to synthesize ring-fused quinazolinones for the first time. The concise, mild and photocatalyst- and oxidant-free conditions, as well as the good functional group tolerance, render this protocol a green and convenient strategy for synthesizing polycyclic ring-fused quinazolinones. Mechanistic studies indicated that the process might involve a radical pathway.
View Article and Find Full Text PDF