Synthetic multimeric heptyl mannosides as potent antiadhesives of uropathogenic Escherichia coli.

Urinary tract infections caused by uropathogenic Escherichia coli presents a serious communal and nosocomial health problem initiated by bacterial adhesion to the bladder cells. E. coli expresses fimbriae with a mannose-binding adhesin, FimH, at the tip. Heptyl alpha-D-mannoside (HM) is a nanomolar inhibitor of this lectin, preventing adhesion of type 1-piliated E. coli and reducing bacteria levels in a murine cystitis model. Herein, we described the synthesis of multimeric heptyl-mannosides with valencies ranging from one to four by copper-catalyzed azide alkyne cycloaddition (CuAAC). Biological evaluation of the multivalent compounds revealed an increase in potency compared to HM. Inhibition of bladder cell binding highlighted a promising tetravalent derivative with inhibitory concentrations 6000- and 64-fold lower than mannose and HM respectively.