A preliminary exploration of coumarin analogs as novel antimicrobial agents
was carried out to determine the basic features of the structure responsib
le for the observed biological activity. The substituents ester or carboxyl
ic acid on the coumarin ring were needed to have potent inhibitory activity
against both Gram-positive and Gram-negative bacteria. The presence of phe
nolic hydroxyl group and/or carboxylic acid was necessary to possess higher
activity against Helicobacter pylori.