Abstract EN:

Positron Emission Tomography has emerged as a major technique of molecular imaging for the visualization and understanding of biological targets or phenomena. Indeed, thanks to its excellent sensitivity and the minor structural modifications of the radio-labeled compounds following introduction of the selected radio-isotope, there is almost no limitation in terms of targeted substrates. For example, in the case of sensitive substrates such as peptides or proteins, which are increasingly proposed as biological targets, the introduction of the radio-isotope under mild conditions is ensured by means of a prosthetic group. As a proof of its interest, PET has now been combined with other imaging techniques, such as fluorescent optical imaging or MRI, to build bimodal sensors. This growing area represents a breakthrough in the field of molecular imaging. During this PhD work, new prosthetic groups based on sultones units were synthesized. The advantageous properties of sultones have been used for the automated radio-syntheses of these prosthetic groups, which could be applied to the radio-labeling of a bio-relevant peptide. Our research interests then focused on the synthesis of fluorinated organic fluorophores, as preliminary work for the preparation of bimodal sensors. We especially designed a general way to radio-label and water-solubilize amino-based fluorophores through an efficient acylation reaction involving a previously-designed prosthetic group. This new strategy was applied for the preparation of a radio-fluorinated cyanine whose spectral properties are suitable for in vivo application.