RT Journal Article
T1 Firefly luciferin precursor 2-cyano-6-hydroxybenzothiazole: Fluorescence à la carte controlled by solvent and acidity
A1 Jadhav, Ankita S.
A1 Carreira Blanco, Carlos
A1 Fernández Rodríguez, Berta
A1 González Fernández, Sonia
A1 Malkhede, Dipalee D.
A1 Mosquera González, Manuel
A1 Ríos Rodríguez, María del Carmen
A1 Rodríguez-Prieto, Flor
K1 Fluorescence
K1 Molecular probe
K1 Excited-state proton transfer
K1 Photoacid
K1 Photobase
AB 2-Cyano-6-hydroxybenzothiazole (CBTOH) is a key intermediate in the biosynthesis of D-luciferin, also used for its chemical synthesis and as luciferin bioluminescence precursor for chemical analysis. We characterized CBTOH and its O-methylated derivative by UV–vis absorption, by steady-state and time-resolved fluorescence spectroscopy, and by density functional theory (DFT) quantum mechanical calculations. Both the acidity of the hydroxyl group and the basicity of the thiazole nitrogen strongly increase upon electronic excitation, triggering solvent- and acidity-dependent deprotonation and protonation processes, with concomitant changes in the fluorescence properties. DFT and time-dependent DFT calculations revealed the existence of a charge displacement that takes place in the excited state from the phenol moiety to the cyanothiazole group for the neutral and the cationic forms of CBTOH. This study reveals CBTOH as the first member of a new class of small dyes with strong photoacid and photobase character, its rich excited-state behavior allowing modulation of its fluorescence properties through solvent and acidity changes. These features make CBTOH a potentially useful fluorescent probe
PB Elsevier
SN 0143-7208
YR 2020
FD 2020
LK http://hdl.handle.net/10347/28829
UL http://hdl.handle.net/10347/28829
LA eng
NO Dyes and Pigments 2020, 177, 108285. DOI: 10.1016/j.dyepig.2020.108285
NO This work has received financial support from Gobierno de España, Ministerio de Economía y Competitividad (Grant CTQ2014-59020-R), Xunta de Galicia (Grants ED431B 2016/024, ED431B 2019/18, ED431D R2016/007, ED431C 2017/17 and Centro Singular de Investigación de Galicia Accreditation 2019–2022, ED431G 2019/03), and the European Union (European Regional Development Fund – ERDF). Ankita S. Jadhav acknowledges the EU Erasmus Mundus Action II Experts III for a scholarship and the Department of Science and Technology, Government of India for financial support under the Women Scientist Scheme (reference no. SR/WOS-A/CS-138/2018) to carry out this work
DS Minerva
RD 23 abr 2026