Dedicated to Prof. András Lipták on the occasion of his 70th birthday.New double (spin and fluorescence) sensors were synthesized from aminocoumarin, pyrene and 4-nitrobenzofurazan dyes and from five-or six-membered nitroxides or their diamagnetic derivatives with aromatic nucleophylic substitution, Suzuki cross-coupling reaction and acylation reactions. The new compounds exhibit fluorescence emission between 382-529 nm affording various utilization possibilities. Introduction.Fluorescent probes and sensors have attracted attention because of their high sensitivity and an exceptional ease of handling relative to their radioactive counterparts [1]. Connection of a fluorophore with a nitroxide free radical or its sterically hindered amine precursor results in a double (fluorescent and spin) sensor reagent, based on a nitroxide free radical (as an acceptor) fluorescence emission quenching of a fluorophore (as a donor) and the mechanism of the quenching has been well-documented in several cases [2,3]. The redox-status of the nitroxide or its amine precursor has a great influence on fluorescence emission intensity and this idea was utilized in design of new double sensor reagents. These reagents can be used in analytical chemistry to detect Reactive Oxygen Species (ROS) by electron spin resonance spectroscopy (EPR) and by fluorescence spectroscopy [4,5] or fluorophore attached nitroxides can be utilized as redox-indicators [6]. In our laboratory several new type donoracceptor pairs have been synthesized based on dansyl [7], aminophthalimide [8], benzazole [9] and 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) [10] type fluorophores. Till now, the most successful one has been the 3-[N-(β-diethylaminoethyl)-N-dansyl] aminomethyl-2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrole, so-called "DanePy", which is widely used in the singlet oxygen detection in plant physiology under oxidative stress conditions [11]. Another challenge in this area is the synthesis of doublelabel molecules combining advantages of the fluorescent labeling and the spin labeling. Because of the dynamic quenching in these donor-acceptor pairs, the lifetime of the
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.