Turning on fluorescent emission from C-alkylation on quinoxaline derivatives.

Org Lett

Department of Materials Chemistry, Sejong Campus, Korea University, Chochiwon, Chung-Nam 339-700, South Korea.

Published: December 2008

Reduction on imine moiety (C=N) of quinoxalines by alkyl-/aryllithiums led to a geometrical change on the quinoxaline ring, thereby perturbing the electronic structure to turn on fluorescence emission. Such a structural change resulted in interrupted cyclic-ring systems with electron-donating amine (sp(3)-type) and electron-accepting imine (sp(2)-type) units bridged by a phenylene unit. Through either alkylation or arylation, a highly polarized electron donor-electron acceptor bipolar system was established in a single molecule with dramatically enhanced PL efficiency (up to 60%).

Download full-text PDF

Source
http://dx.doi.org/10.1021/ol802287kDOI Listing

Publication Analysis

Top Keywords

turning fluorescent
4
fluorescent emission
4
emission c-alkylation
4
c-alkylation quinoxaline
4
quinoxaline derivatives
4
derivatives reduction
4
reduction imine
4
imine moiety
4
moiety c=n
4
c=n quinoxalines
4

Similar Publications

The innate immune response serves as the primary defense against viral infections, with the recognition of viral nucleic acids by pattern recognition receptors (PRRs) initiating antiviral responses. Mitochondrial antiviral-signaling protein (MAVS) acts as a pivotal adaptor protein in the RIG-I pathway. Alternative splicing further diversifies MAVS isoforms.

View Article and Find Full Text PDF

This study focused on the effect of ultrasound-assisted immersion freezing (UIF) with different ultrasound power (200, 400, 600 W) on the physicochemical and digestive properties of beef myofibrillar proteins (BMP). The results showed that the solubility and thermal stability of BMP were significantly increased, when treated with 400 W ultrasound, and the α-helix, β-sheets, β-turns, and random-coil fractions structures content were higher and the fluorescence intensity was closest to that of the control group, demonstrating enhanced structural stability of BMP. The protein digestibility of the UIF-400 W group was significantly enhanced while the particle size of the digested product was reduced, which proved its enhanced digestion characteristics.

View Article and Find Full Text PDF

Disturbance-Triggered Instant Crystallization Activating Bioinspired Emissive Gels.

Angew Chem Int Ed Engl

January 2025

Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Key Laboratory of Advanced Marine Materials, 1219 Zhongguan West Road, 315201, Ningbo, CHINA.

Many marine organisms feature sensitive sensory-perceptual systems to sense the surrounding environment and respond to disturbance with intense bioluminescence. However, it remains a great challenge to develop artificial materials that can sense external disturbance and simultaneously activate intense luminescence, although such materials are attractive for visual sensing and intelligent displays. Herein, we present a new class of bioinspired smart gels constructed by integrating hydrophilic polymeric networks, metastable supersaturated salt and fluorophores containing heterogenic atoms.

View Article and Find Full Text PDF

Behavioral and molecular neurotoxicity of thermally degraded polystyrene in Caenorhabditis elegans.

J Hazard Mater

January 2025

Institute for Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China. Electronic address:

Microplastics are pervasive environmental contaminants found across diverse ecosystems, inducing toxic effects in a wide range of organisms. However, the neurotoxic effects of thermally degraded polystyrene (T-PS) and its underlying mechanisms remain poorly unexplored. In this study, Caenorhabditis elegans was exposed to environmentally relevant concentrations of T-PS (0.

View Article and Find Full Text PDF

The real-time measurement of the content of impurities such as iron and aluminium ions is one of the keys to quality evaluation in the production process of high-purity lithium carbonate; however, impurity detection has been a time-consuming process for many years, which limits the optimisation of the production of high-purity lithium carbonate. In this context, this work explores the possibility of using water-soluble fluorescent probes for the rapid detection of impurity ions. Salicylaldehyde was modified with the hydrophilic group dl-alanine to synthesise a water-soluble Al fluorescent probe (Probe A).

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!