Two-photon absorption and cell imaging of fluorene-functionalized epicocconone analogues

Samuel Oger (1) , Damien Schapman (2) , Romain Mougeot (1) , Stéphane Leleu (1) , Noëlle Lascoux (3) , Patrice L. Baldeck (3) , Magalie Bénard (2) , Thibault Gallavardin (1) , Ludovic Galas (2) , Xavier Franck (1)

1 COBRA - Chimie Organique et Bioorganique : Réactivité et Analyse
2 PRIMACEN - Plate-Forme de Recherche en Imagerie Cellulaire de Haute-Normandie
3 LC - Laboratoire de Chimie - UMR5182

Epicocconone 1 is a natural chromophore isolated from the fungus Epicoccum nigrum that has shown applications in proteomics and fluorescent microscopy thanks to its unique pro‐fluorescence properties. The modification of the skeleton of the natural product by replacing the triene side chain by a fluorenyl scaffold can noticeably increase the fluorophore's absorption coefficient. The synthesis of the analogues of the natural product has been made possible by the use of a palladium‐catalyzed carbonylation reaction, allowing the construction of the β‐keto‐dioxinone key intermediate. Two‐photon absorption cross‐section measurements of the fluorenyl epicocconone analogues show a structure dependency with values ranging from 60 to 280 GM and live cell imaging show intense staining of intracellular vesicle‐like structures around the nucleus.

Keywords: dioxinone; cell imaging; epicocconone; fluorene; two-photon

Domains: Chemical Sciences; Organic chemistry

Samuel Oger, Damien Schapman, Romain Mougeot, Stéphane Leleu, Noëlle Lascoux, et al.. Two-photon absorption and cell imaging of fluorene-functionalized epicocconone analogues. Chemistry - A European Journal, 2019, 25 (46), pp.10954-10964. ⟨10.1002/chem.201902731⟩. ⟨hal-02170780⟩