5-exo-trig Cyclization of an aryl radical to the nitrogen of an azomethine is used as the key annulating step in a modular preparation of 2,3-cis- and trans-disubstituted indolines. The precursors are readily prepared by phase-transfer-catalyzed Michael addition of a glycine Schiff base to a variety of acceptors. When the more reactive alkylidene malonate Michael acceptors are implemented, a one-pot three-component coupling is possible. The net result is a convergent [3 + 2] coupling strategy for the construction of highly functionalized indolines, a substructure occurring in numerous biologically active natural products.
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http://dx.doi.org/10.1021/jo702523u | DOI Listing |
Phytochem Anal
January 2025
Department of Pharmacy, Shanghai Changhai Hospital, Naval Medical University, Shanghai, China.
Introduction: Antimicrobial resistance and free radical-mediated oxidative stress and inflammation involved in many pathological processes have become treatment challenges. One strategy is to search for antimicrobial and antioxidant ingredients from natural aromatic plants. This study established a rapid and high-throughput effect-component analysis method to screen active ingredients from Ligusticum chuanxiong essential oil (CXEO).
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, College of Chemistry and Chemical Engineering, Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, Xiamen 361005, China.
Nitrogen fixation is essential for the sustainable development of both human society and the environment. Due to the chemical inertness of the N≡N bond, the traditional Haber-Bosch process operates under extreme conditions, making nitrogen fixation under ambient conditions highly desirable but challenging. In this study, we present an ultrasonic atomizing microdroplet method that achieves nitrogen fixation using water and air under ambient conditions in a rationally designed sealed device, without the need for any catalyst.
View Article and Find Full Text PDFJ Biomater Sci Polym Ed
January 2025
Department of Medical Affairs, Curie Sciences, Samastipur, Bihar, India.
Introduction: Free radical-mediated oxidative renal tubular injury secondary to hyperoxaluria is a proposed mechanism in the formation of calcium oxalate stones. Vitamin E, an important physiologic antioxidant, has been shown in rat models to prevent calcium oxalate crystal deposition. Our objective was to determine if low dietary vitamin E intake was associated with a higher incidence of stones.
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; Key Laboratory of Environment Correlative Dietology, Huazhong Agricultural University, Ministry of Education, China. Electronic address:
Heterogeneous hygrothermal degradation (HHTD) efficiently produces partially depolymerized konjac glucomannan (KGM). However, KGM degrades considerably faster in oxygen-containing air packaging than in oxygen-free vacuum packaging. This study investigated the effects of different atmosphere conditions on the molecular structure of KGM and the radicals involved in its degradation system.
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