SYNTHESIS AND ANTIBACTERIAL ACTIVITYOF(E)- HYDROXYCHALCONES: 2′-HYDROXY-2-BROMOCHALCONE IS POTENTIALLY ANTIBACTERIALAGAINSTStaphylococcus aureus AND Shigella sonnei

Fourteen (E)-hydroxychalcones (3a-3n) were synthesised through the Claisen-Schmidt condensation. The reactionbetween arylmethyl ketones and aromatic aldehydes in the presence of NaOH afforded corresponding(E)- hydroxychalcones in good to excellent yields. The synthesised compounds were identified by spectroscopy (UV, IR, 1H NMR and 13C NMR). The antibacterial activity of these (E)-hydroxychalcones was studied against Gram-positive(Staphylococcus aureus) and Gram-negative (Escherichia coli, Salmonella typhi and Shigella sonnei) bacterial strains. (E)-3-(2-Bromophenyl)-1-(2-hydroxyphenyl)prop-2-en-1-one (3d) had displayed a high antibacterial activityagainst S. aureus and S. sonnei with the MIC value of 0.78 mg/mL. Parent chalcones, viz. (E)-3-(furan-2-yl)-1- phenylprop-2-en-1-one (P1) and (E)-1,3-diphenylprop-2-en-1-one (P2), containing furyl and phenyl Bring, respectively, were also used for a comparative study.