A new series of push-pull arylvinyldiazines has been efficiently prepared by aldol condensation between the appropriate methyldiazine and aromatic aldehyde. The optical absorption and emission properties of these chromophores were studied in different solvents and media. These compounds act as polarity sensors with a strong positive emission solvatochromism. This behavior suggests a highly polar emitting state, which is characteristic of compounds that undergo an internal charge transfer upon excitation. These molecules also exhibit halochromic properties and are potential colorimetric and luminescence pH sensors. The second-order nonlinear properties have been investigated for some of the compounds, and large and positive μβ are obtained, in particular, for pyrimidine derivatives.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/jo3004919 | DOI Listing |
J Org Chem
January 2025
Department of Materials Science and Engineering, Institute of Science Tokyo, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8552, Japan.
A series of 1,1,4,4-tetracyanobuta-1,3-diene (TCBD) derivatives with various heterocyclic moieties, including pyridine, carbazole, indole, and benzothiadiazole, was newly synthesized through a [2 + 2] cycloaddition-retroelectrocyclization reaction. Symmetric electron-rich 1,3-butadiynes with end-capped heterocyclic substituents were reacted with tetracyanoethylene (TCNE), yielding the target TCBD products in 60-80% yields under ambient or mild heating conditions. The thermal stability and optical and electrochemical properties of both 1,3-butadiyne precursors and the corresponding TCBD derivatives were investigated by using thermogravimetric analysis (TGA), UV-vis spectroscopy, and cyclic voltammetry (CV).
View Article and Find Full Text PDFbioRxiv
December 2024
Department of Psychology, Vanderbilt University, Nashville, TN, USA.
Neurophysiology studies propose that predictive coding is implemented via alpha/beta (8-30 Hz) rhythms that prepare specific pathways to process predicted inputs. This leads to a state of relative inhibition, reducing feedforward gamma (40-90 Hz) rhythms and spiking to predictable inputs. We refer to this model as predictive routing.
View Article and Find Full Text PDFACS Nano
January 2025
State Key Laboratory of Fine Chemicals, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518055, China.
Biofilm-induced chronic bacterial infections represent a significant challenge in modern medicine due to their resistance to conventional antibiotic treatments. Although photodynamic therapy (PDT) has emerged as a promising antibiotic-free antibacterial strategy, the hypoxic condition within biofilms and the lack of an effective local drug delivery system have limited the clinical effectiveness of photosensitizer (PS) agents. Herein, we propose a type of charge regulation-enhanced type I PS-loaded hydrogel dressing for treating biofilm infection.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
January 2025
School of Basic Medical Sciences, Guizhou Medical University, Guiyang 550025, PR China. Electronic address:
Non-alcoholic fatty liver disease (NAFLD) is a disease closely associated with metabolic abnormalities. Lipid droplets (LDs) serve as organelles that store intracellular neutral lipids and maintain cellular energy homeostasis. Their abnormalities can cause metabolic disorders and disease, which is also one of the distinctive characteristics of NAFLD patients.
View Article and Find Full Text PDFInorg Chem
January 2025
Institute of Chemistry, University of Silesia, Szkolna 9, 40-006 Katowice, Poland.
This paper provides extensive studies of [IrCl(Ph-py)(morph-CH-terpy-κN)]PF (), [Ir(Ph-py)(morph-CH-terpy-κN)]PF (), [IrCl(Ph-py)(Ph-terpy-κN)]PF (), and [Ir(Ph-py)(Ph-terpy-κN)]PF () designed to demonstrate the possibility of controlling the photophysical properties of mono- and bis-cyclometalated complexes [IrCl(Ph-py)(R-CH-terpy-κN)]PF and [Ir(Ph-py)(R-CH-terpy-κN)]PF through a remote electron-donating substituent introduced into the 4'-position of 2,2':6',2″-terpyridine (terpy) via the phenyl linker. The attachment of the morpholinyl (morph) group was evidenced to induce dramatic changes in the emission characteristics of the monocyclometalated Ir(III) systems with coordinated R-CH-terpy ligand (κN). In solution, the obtained complex [IrCl(Ph-py)(morph-CH-terpy-κN)]PF was found to be a rare example of dual-emissive Ir(III) systems.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!