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Abstract This thesis is concerned with microbially derived cis-3,5-cyclohexadiene-1,2- dihydroxy-1-carboxylic acid and its iron tricarbonyl derivatives as precursors for the efficient and practical synthesis of useful products. The opening chapter consists of a review of the biocatalytic cis-dihydroxylation process including its mechanism and applications in synthesis. In a Chapter 2 the utility of cyclohexadiene iron tricarbonyl complexes to date is outlined, with particular focus on their preparation and reactivity. Synthetic routes towards the synthesis of the natural products gabaculine and carbazole alkaloids are described, followed by the preparation of tarniflu and general methods of decomplexation. Chapter 3 presents the synthesis of novel iron tricarbonyl complexes and studies on their reactivity are disclosed. (Figure A.) Chapter 4 describes the formation of a new rearrangement product of the acetonide protected iron tricarbonyl complexes. In order to validate this process, independent studies with labelled compounds have been employed. Following Myers' procedure for microbial oxidation of p-deutero-benzoic acid, quantities of a novel deutero-diol product were successfully prepared and used to elucidate the mechanism of the rearrangement process. (Figure B) In Chapter 5 the formation of the f]5 cyclohexadienyl complexes is discussed followed by the outcome of the nucleophilic addition products. Chapter 7 provides detailed specific and general procedures for the synthesis of the compounds described within this thesis, along with their characterisation data. The appendices provide analytical support to this thesis and list of publications. Each chapter includes a separate discussion of the results and Chapter 6 provides an overall summary and suggestions for possible future work.

L'imagerie a pris une importance croissante dans l'étude des processus biologiques. L'utilisation de la microscopie de fluorescence a notamment favorisé le développement de nombreuses molécules sondes pour le marquage et la visualisation de biomolécules en milieu biologique complexe. D'autre part, des techniques d'imagerie complémentaires émergent, comme la microspectroscopie infrarouge. Les complexes organométalliques ont un potentiel important comme outils pour l'imagerie biologique, car ils peuvent combiner sur un même cœur moléculaire des propriétés permettant leur détection par différents types d'imagerie. En particulier, des complexes rhénium tricarbonyl ont été utilisés comme sondes pour l'imagerie multimodale. Ces " SCoMPIs " (Single Core Multimodal Probes for the Imaging) sont luminescents et présentent des signaux infrarouge et de fluorescence X intenses et qui permettent leur détection spécifique en milieu biologique. Dans cette étude, nous nous sommes intéressés aux possibilités d'imagerie multimodale de peptides et de protéines exogènes ou endogènes. Différents SCoMPIs ont été préparés et caractérisés, permettant le marquage N-terminal de peptides, le marquage d'une protéine exogène (homéodomaine) via une réaction thiol-maléimide ou le marquage par affinité d'une protéine endogène (anhydrase carbonique). L'évolution des propriétés de luminescence de SCoMPIs en fonction de l'environnement a été étudiée. Les imageries de luminescence et infrarouge ont permis la détection des peptides en contexte cellulaire, mais pas des protéines marquées avec des SCoMPIs. En revanche, il a été possible de détecter ces faibles quantités par microspectroscopie de fluorescence X. / Bioimaging is now widely used for the study of biological processes. The expansion of fluorescence microscopy has led to the development of small chemical probes for the labelling and imaging of biomolecules in complex biological environments. Alternative imaging techniques, such as infrared microspectroscopy, are also emerging. Organometallic complexes have a great potential as tools for bioimaging, since they can combine on a single molecular core properties enabling their detection by various imaging techniques. In particular, rhenium tricarbonyl complexes have been used for multimodal imaging. These “SCoMPIs” (Single Core Multimodal Probes for the Imaging) are luminescent and exhibit intense, specific infrared and X-ray fluorescence signals, which make possible their multimodal detection in biological media. In this study, we focused on the possibility to perform the multimodal imaging of SCoMPI-labelled peptides and proteins in cells. Various SCoMPIs were prepared and characterized, that were suitable for N-terminal labelling of peptides, labelling of an exogenous protein (homeodomain) through thiol-maleimide labelling, or the affinity-guided labelling of endogenous proteins (carbonic anhydrases). Dependance on the luminescence properties of SCoMPIs with their environment was investigated. SCoMPI-labelled peptides could be easily detected by luminescence and infrared imaging, which was not the case for SCoMPI-labelled proteins. However, it was possible to detect these small amounts of proteins by X-ray fluorescence microspectroscopy.