Effect-Directed Synthesis of PhoP/PhoQ Inhibitors to Regulate Salmonella Virulence.

Salmonella spp. are among the leading bacterial causes of foodborne infections. The PhoP/PhoQ two-component regulatory system serves as a master virulence regulator in Salmonella. Although PhoP/PhoQ represents an ideal target for disarming Salmonella virulence, it has very few inhibitors reported so far. We describe a novel platform by which an inhibitor was selected out of around 185 compounds directly from reaction media containing thiosemicarbazones and mono-, di-, and trihydrazones. To achieve this, tandem library preparation, thin-layer chromatography (TLC) bioautography, and effect-directed deconvolution were applied. We illustrate the potential of this effect-directed synthesis for the identification of new useful bioactive compounds for the food field.