Search results

JuryProf. Johan WOUTERS (UNamur), ChairProf. Steve LANNERS (UNamur), secretaryProf. Stéphane VINCENT (UNamur)Prof. Johan WINNE (UGent)Prof. Andrew MITCHELL (Illinois State University)AbstractTaxpropellane is a taxane complex with a particularly elaborate structure. Although its biological properties are still unknown, its structural complexity makes it a synthetic target of choice. The approach developed in this thesis is based on a retrosynthetic simplification toward a bicyclo[5.4.0]undecane, the preparation of which requires new methodologies, in particular the development of an (5+2) oxydopyrylium cycloaddition using a temporary bridge to construct the required bicyclic compounds.Oxydopyrylium species are highly reactive aromatic intermediates, commonly used to synthesize 7-membered rings via cycloaddition reactions. Their use for intermolecular cycloadditions is severely limited due to their rapid dimerization when the dipolarophile is not sufficiently reactive. The strategy developed in this work relies on the use of a temporary ether-type linker to overcome this limitation. Numerous bicyclic compounds have thus been efficiently synthesized using this methodology. We have shown that this diastereoselectivity depends solely on how the two reactive fragments are linked. Thus, the proposed methodology allows for complete control of stereoselectivity. The cleavage of the linker has also been investigated. This can be achieved in two different ways. This work extends the use of oxidopyrylium ions in synthesis, and this methodology will be applied to the total synthesis of taxpropellane, following the synthesis of a suitable dipolarophile also described here.

JuryProf. Joseph WINKIN (UNamur), ChairProf. Timoteo CARLETTI (UNamur), SecretaryProf. Alexandre MAUROY (UNamur)Prof. Malbor ASLLANI (Florida State University)Dr. Maxime LUCAS (UNamur)Dr. Riccardo MUOLO (RIKEN Institute)AbstractSynchronization is a ubiquitous phenomenon in the world around us. It is a crucial feature that ensures the proper functioning of many complex systems. The various generators in a power grid must produce alternating current at a common frequency, and the brain’s cortical regions synchronize their activities to enable the brain to control the human body. These systems can be modeled as coupled oscillators, as in the famous Kuramoto model, where entities interact in pairs so that they synchronize globally.However, synchronization can also pose a problem. For instance, excessive synchronization of brain dynamics leads to pathological states such as epileptic seizures. It is therefore necessary to develop methods that reduce global synchronization by locally controlling the dynamics of certain oscillators. In particular, a control scheme based on a Hamiltonian framework has been designed to effectively desynchronize the Kuramoto model.Nevertheless, some limitations remain. First, the controlled nodes are selected at random without considering their specific characteristics. Second, this method is designed to control systems with a network structure—that is, with pairwise coupling—whereas many recent studies have demonstrated the importance of higher-order networks, i.e., group interactions, in modeling such systems.In this Ph.D. thesis, we aim to address these gaps through several studies. We explore the optimal method for selecting controlled nodes to maximize control efficiency, investigate the method’s ability to desynchronize systems with higher-order interactions, and develop a new control method tailored to this framework.Our results not only improve these control techniques but also offer novel perspectives on the synchronization of complex systems. They allow us to better understand the influence of each local entity on collective behavior and the role played by interactions of different orders. Among other things, they shed light on the non-monotonic relationship between synchronization capacity and the strength of higher-order interactions.

Program Overview This event will take place over two exciting days, featuring a diverse program designed to offer a dynamic and interactive experience for all participants. The entire symposium will be conducted in English.On Wednesday, December 9, and Thursday, December 10, two days of scientific and technical sessions will be dedicated to the topics of alternative proteins, the microbiome, and functional ingredients.On Wednesday, December 9, there will be a public lecture (in English) presented by Dr. Patrice Cani on the topic “Nourishing Your Gut: Nutrition, Microbiota, and Health.”For experienced researchers and group leaders, we are organizing a third day on December 11 dedicated to international collaboration, including laboratory visits and a workshop focused on establishing structured collaborative projects. Separate registration is requiredOverview of the ThemesThis symposium is structured around the three projects in the FoodWal portfolio, while pushing their boundaries and framing them within a “One Health” approach.The session titled “Building Sustainable Value Chains for Alternative Proteins: from protein sources to the development of healthy food products” will provide an opportunity to present scientific and technological advances in the creation and characterization of alternative protein sources and products, as well as socioeconomic perspectives on the development, maintenance, and growth of sustainable value chains for alternative proteins.The session titled “Research on the Microbiome and Microbiotics: Innovation in Nutrition for Better Health” will present scientific advances in the characterization, understanding, and modulation of the microbiome, as well as cutting-edge technologies aimed at developing innovative microbiotics.Finally, the session titled “Functional Ingredients and Bioactive Compounds: Food Science and Biotechnology for Health” will focus on scientific advances in the identification, characterization, and understanding of the mechanisms of action of functional ingredients, as well as cutting-edge technologies designed to develop and produce innovative functional ingredients. More information on the FoodWal website Je m'inscris

JuryProf. Steve LANNERS (UNamur), ChairProf. Johan WOUTERS (UNamur), SecretaryProf. Pierre FRANCOTTE (ULiège)Dr. Marie HAUFROID (UCB)Prof. Lionel POCHET (UNamur)AbstractCurrently, Mycobacterium tuberculosis remains the second deadliest infectious agent in the world, responsible for 1.6 million deaths in 2021. The burden and cost of current treatment (6 months and 4,000 euros), coupled with the alarming emergence of antibiotic-resistant strains, underscore the absolute urgency of developing new therapeutic molecules. This study focuses on the Mycobacterium tuberculosis phosphoserine phosphatase (MtSerB2), an enzyme essential for serine biosynthesis and vital to the pathogen’s survival. Furthermore, this protein plays a key role in host invasion (through its interactions with the NF-κB factor and the cellular cytoskeleton), making MtSerB2 a prime therapeutic target for the development of new, potent anti-tuberculosis drugs.One of the innovative strategies explored in this thesis is based on destabilizing the protein’s structure (disruption of protein structure). The goal is to design a molecule capable of disrupting the enzyme’s conformation, thereby causing it to lose its catalytic activity. This new class of molecules is expected to exhibit significantly higher selectivity for MtSerB2 compared to its human homolog, human phosphoserine phosphatase (hPSP).To this end, the Mycobacterium avium phosphoserine phosphatase (MaSerB) was initially used as a model system, justified by its 83% sequence identity with MtSerB2 and its propensity to crystallize rapidly. Initially, a virtual screening of drugs already available on the market was conducted to identify potential inhibitors of MaSerB. Enzymatic assays based on malachite green detectionwere then performed to evaluate the inhibitory activity of the various candidates. The results demonstrated increased selectivity of these compounds for dimeric proteins (MtSerB2 and MaSerB) compared to the human enzyme hPSP.Notably, subsequent enzymatic assays conducted directly on MtSerB2 revealed response profiles that differed from those observed with the MaSerB model. To elucidate the molecular basis of these differences, the structure of the protein in its ligand-bound state is currently being investigated. To this end, protein-inhibitor complexes have been crystallized and will be analyzed by X-ray diffraction.