Discovery of xanthone-based nitric oxide donors targeting biofilm clearance.

Bacteria biofilm infection seriously challenges clinical drug therapy. Nitric oxide (NO) was reported to disperse biofilm, eliminate bacteria resistance and kill bacteria. In this study, on the basis of membrane targeting of α-mangostin (α-MG) and the dispersion effect of NO on bacteria biofilms, we designed and synthesized 30 NO donors that α-MG was conjugated with a nitrobenzene or a nitrate and other four representative reference derivatives. Compound 23 with 2-chloro-4-nitrobenzoyl introduced in the position C6 of α-MG exhibited the prominent ability to eradicate Staphylococcous aureus biofilm, and a more long-lasting and stable bactericidal effect in vitro, and lower hemolytic activity over α-MG. Moreover, a mouse wound model infected by S. aureus biofilm supported the in vivo reduced bacterial burden closely associated with the NO release from compound 23 that exerted a dispersing effect on biofilms. Therefore, our design strategy can provide a promising and effective solution to intervene in biofilm infection with high specificity.