Design, Antimicrobial Testing, and Molecular Docking Studies of New Chalcone and Pyrimidine Derivatives based on 2-phenyl-1H-pyrazol-3(2H)-one

Background & Objectives: Heterocyclic pyrimidine and pyrazole rings have attracted the interest of medicinal chemists because of their pharmacological potential including antimicrobial activity. Based on molecular hybridization, new chalcones 6a-g and pyrimidines 7a-g based on a pyrazole scaffold were designed. Methods: The synthesis of these compounds involved mild condensation reactions between compound 4 and various aromatic aldehydes in a mixture of ethanol/NaOH (95:5 v/v) to give the corresponding chalcones 6a-g. These chalcones were further reacted with urea in the presence of a base in ethanol to produce the pyrimidine derivatives 7a-g. These new candidates were screened for their in vitro antimicrobial activities and molecular docking studies were evaluated. Results: The antibacterial and antifungal studies of all synthesized compounds against the strains tested showed that compounds 6c, d, and 7c, d exhibited the highest antibacterial and antifungal activities. In addition, the structure-activity relationship and docking studies are discussed. Conclusion: The synthesized compounds 6c, 6d, 7c, and 7d showed the highest antibacterial and antifungal activities against the tested strains.