Alkene oxyacylation is a new strategy for the preparation of β-oxygenated ketones. Now, with Ir catalysis and low-cost salicylate esters, alkene oxyacylation can be promoted by simple and versatile hydroxyl directing groups. This paper discusses catalyst optimization, substituent effects, mechanistic experiments, and the challenges associated with asymmetric catalysis. Crossover experiments point to several key steps of the mechanism being reversible, including the most likely enantiodetermining steps. The oxyacylation products are also prone to racemization without catalyst when heated alone; however, crossover is not observed without catalyst. These observations account for the low levels of enantioinduction in alkene oxyacylation. The versatility of the hydroxyl directing group is highlighted by demonstrating further transformations of the products.
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Food Chem X
January 2025
Hubei Key Laboratory of Edible Wild Plants Conservation & Utilization, College of Life Sciences, Hubei Normal University, Huangshi 435002, China.
The study aimed to assess the oxidative modification behavior of bovine myofibrillar proteins (MPs) cysteines (Cys) by hydroxyl radical (·OH) through the construction of an in vitr Fenton reaction system. The ·OH generated by the Fenton reaction induced large-scale oxidative modification of Cys, and redox proteomics identified a total of 1192 differential oxidation sites (Dos), 59 Dos were located in the MPs structure. The Cys of actin (17 Dos), myosin/myomesin (16 Dos), tenascin (12 Dos) and sarcomere (10 Dos) in the MPs structure showed active oxidative modification behavior towards ·OH, especially with the "-C-X-X-X-X-W-" structure amino acid sequence showed high sensitivity.
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 PDFMetab Eng
January 2025
Shenzhen Key Laboratory for the Intelligent Microbial Manufacturing of Medicines, Key Laboratory of Quantitative Synthetic Biology, Center for Synthetic Biochemistry, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, CN; University of Chinese Academy of Sciences,Beijing, CN. Electronic address:
10-hydroxy-2-decenoic acid (10-HDA), a unique unsaturated fatty acid present in royal jelly, has attracted considerable interest due to its potential medical applications. However, its low concentration in royal jelly and complex conformational structure present challenges for large-scale production. In this study, we designed and constructed a de novo biosynthetic pathway for 10-HDA in Escherichia coli.
View Article and Find Full Text PDFChem Sci
January 2025
Applied Chemistry and Environmental Science, School of Science, STEM College, RMIT University Melbourne Victoria 3000 Australia
High-temperature reduction of TiO causes the gradual formation of structural defects, leading to oxygen vacancy planar defects and giving rise to Magnéli phases, which are substoichiometric titanium oxides that follow the formula Ti O, with 4 ≤ ≤ 9. A high concentration of defects provides several possible configurations for Ti and Ti within the crystal, with the variation in charge ordered states changing the electronic structure of the material. The changes in crystal and electronic structures of Magnéli phases introduce unique properties absent in TiO, facilitating their diverse applications.
View Article and Find Full Text PDFAnal Chem
January 2025
Institute of Physical Science and Information Technology, Information Materials and Intelligent Sensing Laboratory of Anhui Province, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei, Anhui 230601, China.
Real-time monitoring of the dynamics of cytosolic RNA-protein condensates, termed stress granules (SGs), is vital for understanding their biological roles in stress response and related disease treatment but is challenging due to the lack of simple and accurate methods. Compared with protein visualization that requires complex transfection procedures, direct RNA labeling offers an ideal alternative for tracking SG dynamics in living cells. Here, we propose a novel molecular design strategy to construct a near-infrared RNA-specific fluorescent probe () for tracking SGs in living cells.
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