An efficient enantioselective α-amination of 2-substituted 3-indolinones has been achieved for the first time using hydroquinidine as a chiral catalyst through an aza-Michael reaction. The desired α-hydrazino esters are obtained in excellent yields with high enantiomeric excess leading to a quaternary stereocenter with a broad substrate scope.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/acs.orglett.6b03473 | DOI Listing |
Nat Prod Res
January 2025
Institute of Chemistry, São Paulo State University (Unesp), Araraquara, Brazil.
(Aristolochiaceae), commonly known as the Brazilian Dutchman's pipe, is cultivated globally as an ornamental vine, admired for the unique shape of its large flowers. In our ongoing research into the chemical composition of , the ethanol extract from its seeds was fractionated using chromatographic techniques, resulting in the isolation and identification of allantoin, along with the lignans kobusin, eudesmin, and methylarctigenin. The fractions were further analysed by NMR and GC - EI/MS, employing a molecular networking approach and retention index comparison, which led to the annotation of four sterols, eleven aliphatic alcohols, one saturated fatty acid, two unsaturated fatty acids, ten esters of saturated fatty acids, ten esters of unsaturated fatty acids, and one lactone.
View Article and Find Full Text PDFArch Toxicol
January 2025
Cosmetics Europe, Brussels, Belgium.
Grouping of chemicals has been proposed as a strategy to speed up the screening and identification of potential substances of concern among the broad chemical universe under REACH. Such grouping is usually based on shared structural features and should only be used for the prioritization objectives. However, additional considerations (as well as structural similarity) are needed, e.
View Article and Find Full Text PDFAMB Express
January 2025
Faculty of Basic Sciences, King Salman International University, South Sinai City, 46612, Egypt.
The rise of antimicrobial-resistant microorganisms (AMR) poses a significant global challenge to human health and economic stability. In response, various scientific communities are seeking safe alternatives to antibiotics. This study comprehensively investigates the antibacterial effects of red dye derived from Monascus purpureus against three bacterial pathogens: Salmonella typhimurium ATCC14028, Escherichia coli ATCC8739, and Enterococcus faecalis ATCC25923.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Physics, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea.
Despite recent advancements in organic photovoltaics (OPVs), further improvements in power conversion efficiency (PCE) and device lifetime are necessary for commercial viability. Strategies such as optimizing the molecular orientation and minimizing the charge traps of organic films are particularly effective in enhancing photovoltaic performance. In this study, we successfully utilized vacuum electrospray deposition (VESD) to achieve favourable face-on stacking geometries while preserving the integrity of the interfaces in poly(3-hexylthiophene-2,5-diyl) (P3HT): [6,6]-phenyl-C-butyric acid methyl ester (PCBM) bulk heterojunction (BHJ) films.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Key Laboratory of Chem-Biosensing of Anhui Province, Key Laboratory of Functional Molecular Solids of Anhui Province, College of Chemistry and Materials Science, Anhui Normal University, Wuhu 241000, Anhui, China. Electronic address:
Adsorption and biodegradation are two important means to remove the pollutants from the environment, but how to combine them and improve the catalytic performance and stability of free enzyme are facing great challenges. Herein, lipase from Candida rugosa (CRL) was immobilized into bimetallic ZnCo-MOF by biomineralization, which not only significantly improved the catalytic activity and stability of CRL but also endowed it with excellent reusability. Furthermore, CRL@ZnCo-MOF established a synergetic system of combined adsorption and enzymatic degradation for the sustainable removal of dibutyl phthalate (DBP) in actual water environment.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!