Theoretical Study of the Nontraditional Enol-Based Photoacidity of Firefly Oxyluciferin

• Type: Article in International Scientific Journal
• Date: 2015

Authors

Luis Pinto da Silva (Author) Other; Joaquim C G E Esteves da Silva (Author) FCUP

Journal

Title: ChemPhysChem

Vol. 16

Pages: 455-464

ISSN: 1439-4235

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 19 Citations

Scopus - 19 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-00A-431

DOI: 10.1002/cphc.201402533

Abstract (EN): A theoretical analysis of the enol-based photoacidity of oxyluciferin in water is presented. The basis for this phenomenon is found to be the hydrogen-bonding network that involves the conjugated photobase of oxyluciferin. The hydrogen-bonding network involving the enolate thiazole moiety is stronger than that of the benzothiazole phenolate moiety. Therefore, enolate oxyluciferin should be stabilized versus the phenolate anion. This difference in strength is attributed to the fact that the thiazole moiety has more potential hydrogen-bond acceptors near the proton donor atom than the benzothiazole moiety. Moreover, the phenol-based excited-state proton transfer leads to a decrease in the hydrogen-bond acceptor potential of the thiazole atoms. The ground-state enol-based acidity of oxyluciferin is also studied. This phenomenon can be explained by stabilization of the enolate anion through strengthening of a bond between water and the nitrogen atom of the thiazole ring, in an enol-based proton-transfer-dependent way.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10