[en] In recent years, the prevalence of infectious diseases caused by pathogens and bacteria resistant to antibiotics have increased considerably. Because they are becoming a threat to public health, the development of new antimicrobial agents has become necessary. For this reason, the preparation of a siderophore covalently bonded to a linker has been proposed in this project, for its subsequent conjugation with polymers in order to test it as an antimicrobial. The selected siderophore, that will act as a targeting ligand in the synthetic siderophore-polymer conjugate, was an analog of amonabactin P750, which is one of the siderophores produced by the pathogenic bacterium Aeromonas salmonicida susp. salmonicida, and the chosen linker was a polyethylene glycol (PEG-3). In the development of this project, a retrosynthetic analysis was first proposed for the synthesis of the chosen siderophore coupled to the linker, in which three main substructures were selected: a siderophore substructure formed by a lysine and a catechol (S-7), another siderophore substructure consisting of a glycine, a lysine and a catechol (S-12) and the linker, which contains three ethylene glycol units (C-13). Next, it was possible to synthesize and characterize each of the proposed substructures and successfully connect them to obtain the siderophore coupled with the proposed linker (SC-16). Unfortunately, the coupling tests of the polymers with the synthesized siderophore fragments were unsuccessful. In view of the results obtained and in order to be able to prepare the conjugates of interest, it is proposed to change the coupling reaction conditions and/or use other functionalized polymers.

[gl] Nos últimos anos, aumentou considerablemente a prevalencia de enfermidades infecciosas causadas por patóxenos e a resistencia bacteriana aos antibióticos. Debido a que se están a converter nunha ameaza para a saúde pública, fíxose necesario o desenvolvemento de novos axentes antimicrobianos. Por este motivo, neste Traballo Fin de Grao propúxose a elaboración dun sideróforo unido covalentemente a un conector, para a súa posterior conxugación con polímeros co fin de probalo como antimicrobiano. O sideróforo seleccionado, para dirixirse selectivamente ao conxugado sintético sideróforo-polímero, foi un análogo da amonabactina P750, que é un dos sideróforos producidos pola bacteria patóxena Aeromonas salmonicida susp. salmonicida, mentres que o conector elixido foi un polietilenglicol (PEG-3). No desenvolvemento deste traballo propúxose primeramente unha análise retrosintética para a síntese do sideróforo elixido acoplado ao conector, na que se seleccionaron tres subestruturas principais: unha subestrutura do sideróforo formada por unha lisina e un catecol (S-7), outra subestrutura do sideróforo formada por unha glicina, unha lisina e un catecol (S-12) e o conector, que contén tres unidades de etilenglicol (C-13). A continuación, foi posible sintetizar e caracterizar cada unha das subestruturas propostas e conectalas para obter o sideróforo acoplado ao conector proposto (SC-16). Desafortunadamente, as probas de acoplamento dos polímeros cos fragmentos de sideróforo sintetizados non tiveron éxito. Á vista dos resultados obtidos e para poder preparar os conxugados de interese, proponse variar as condicións da reacción de acoplamento e/ou empregar outros polímeros funcionalizados.