<p>This work presents the synthesis of novel molecules for heterocyclic fused with a pyridine segment by the reaction of chalcones with cyanoethyl acetate in the presence of ammonium acetate. Pyridine derivatives obtained as pyridine compound 2-oxo-4-phenyl-6-(<i>p</i>-tolyl)-1,2-dihydropyridine-3-carbonitrile, were converted into 2-chloro-4-phenyl-6-(p-tolyl)nicotinonitrile and 2-amino-4-phenyl-6-(<i>p</i>-tolyl) nicotinonitrile. In addition, a new series of pyridine and its fused molecules had been synthesized by reaction of 2-amino-4-phenyl-6-(<i>p</i>-tolyl) nicotinonitrile with various compounds. The synthesized compounds have been purified and their structures were elucidated using multiple techniques such as microelemental analysis (C.H.N), FT-IR spectra, ¹³C NMR spectra, and ¹H NMR spectra. All spectra of these techniques have demonstrated the chemical structure of synthesized molecules and proved their purity. Also, antibacterial activities of the synthesized compounds were evaluated against <i>Staphylococcus aureus</i> and <i>Escherichia coli</i>, establishing their potential application as antibacterial agents.</p> Graphical Abstract <p></p>