Fiche publication
Date publication
juin 2023
Journal
The Journal of organic chemistry
Auteurs
Membres identifiés du Cancéropôle Est :
Dr DAVIOUD-CHARVET Elisabeth
,
Dr SPECHT Alexandre
,
Dr ELHABIRI Mourad
Tous les auteurs :
Trometer N, Cichocki B, Chevalier Q, Pécourneau J, Strub JM, Hemmerlin A, Specht A, Davioud-Charvet E, Elhabiri M
Lien Pubmed
Résumé
This work describes the reactivity and properties of fluorinated derivatives ( and ) of plasmodione () and its metabolite, the plasmodione oxide (). Introduction of a fluorine atom on the 2-methyl group markedly alters the redox properties of the 1,4-naphthoquinone electrophore, making the compound highly oxidizing and particularly photoreactive. A fruitful set of analytical methods (electrochemistry, absorption and emission spectrophotometry, and HRMS-ESI) have been used to highlight the products resulting from UV photoirradiation in the absence or presence of selected nucleophiles. With and in the absence of nucleophile, photoreduction generates a highly reactive -quinone methide (-QM) capable of leading to the formation of a homodimer. In the presence of thiol nucleophiles such as β-mercaptoethanol, which was used as a model, -QMs are continuously regenerated in sequential photoredox reactions generating mono- or disulfanylation products as well as various unreported sulfanyl products. Besides, these photoreduced adducts derived from are characterized by a bright yellowish emission due to an excited-state intramolecular proton transfer (ESIPT) process between the dihydronapthoquinone and benzoyl units. In order to evidence the possibility of an intramolecular coupling of the -QM intermediate, a synthetic route to the corresponding anthrones is described. Tautomerization of the targeted anthrones occurs and affords highly fluorescent stable hydroxyl-anthraquinones. Although probable to explain the intense visible fluorescence emission also observed in tobacco BY-2 cells used as a cellular model, these coupling products have never been observed during the photochemical reactions performed in this study. Our data suggest that the observed ESIPT-induced fluorescence most likely corresponds to the generation of alkylated products through reduction species, as demonstrated with the β-mercaptoethanol model. In conclusion, thus acts as a novel (pro)-fluorescent probe for monitoring redox processes and protein alkylation in living cells.
Référence
J Org Chem. 2023 06 2;:
