In this research, Chalcone (M1-10) was prepared by reaction of aromatic aldehydes with substituted acetophenone, through reaction of Chalcone with Malononitrile in an acidic medium, where pyridine compounds (M19-26) were obtained. The bioactivity of the prepared compounds was tested against Gram-negative and Gram-positive bacteria (Klebsellia pneumonia, Pseudomnas putida, Staph aureus, Enterococcus faecalis). the lowest inhibitory concentration compared to (Ciprofloxacin) and the prepared compounds were diagnosed by physical spectrophotometric methods using spectrophotometers. I.R, 1H-NMR, 13C-NMR.