8-Br-quinoline derivatives as sensitizers combining two-photon induced fluorescence and singlet oxygen generation

The present study describes the synthesis of a series of original 8-Br-quinoline derivatives with an arylethynyl moiety at the C6 position, based on Friedländer and Sonogashira coupling key reactions. Investigation of their photophysical and two-photon absorption (2PA) properties reveals that these structures can lead to 2PA chromophores combining fluorescence and singlet oxygen generation properties. As a result, chromophores, which combine significant 2PA responses in the NIR region, good photosensitization ability (ΦΔ=0.4-0.6) and fluorescence properties (Φf=0.2-0.6) have been identified. These multifunctional derivatives hold promise as original dyes for combined two-photon imaging and photodynamic therapy.