RESUMO
A set of molecules including a majority of metal-N-heterocyclic carbene (NHC) complexes (metal=Ag, Cu, and Au) and azolium salts were evaluated by high-throughput screening of their activity against biofilm formation associated with pathogenic bacteria. The anti-planktonic effects were compared in parallel. Representative biofilm-forming strains of various genera were selected (Listeria, Pseudomonas, Staphylococcus, and Escherichia). All the compounds were tested at 1 mg L(-1) by using the BioFilm Ring Test. An information score (IS, sum of the activities) and an activity score (AS, difference between anti-biofilm and anti-planktonic activity) were determined from normalized experimental values to classify the most active molecules against the panel of bacterial strains. With this method we identified lipophilic Ag(I) and Cu(I) complexes possessing aromatic groups on the NHC ligand as the most efficient at inhibiting biofilm formation.
Assuntos
Antibacterianos/química , Biofilmes/efeitos dos fármacos , Complexos de Coordenação/química , Compostos Heterocíclicos/química , Metano/análogos & derivados , Antibacterianos/farmacologia , Biofilmes/crescimento & desenvolvimento , Complexos de Coordenação/farmacologia , Cobre/química , Ouro/química , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/fisiologia , Metano/química , Testes de Sensibilidade Microbiana , Prata/químicaRESUMO
A new strategy was developed for the modification of silver(I) and gold(I) N-heterocyclic carbenes. Azido groups were grafted and used either by copper-catalysed azide-alkyne cycloaddition before metallation or by thermal and "strain-promoted" 1,3-dipolar cycloaddition after metallation to functionalise the metal-NHCs.
RESUMO
A reducing agent-free version of CuAAC able to operate under open air conditions is reported. A readily-synthesizable, hydrophilic and highly stable Cu(I)-NHC allows the clean ligations of unprotected peptides comprising sensitive side chains, at millimolar concentrations.