A series of novel piperazine based cinnamic acid bearing coumarin derivatives were designed and synthesized by piperazine based cinnamic acids esterification with 4‐hydroxycoumarin and characterized by various spectral techniques like infrared, 1H nuclear magnetic resonance (NMR), 13C NMR, and mass. The novel bioactive compounds (7a‐7m) screen their potential against different bacterial and fungal strains. Compound 7g (minimum inhibitory concentration [MIC] = 12.5 µg/ml) exhibited potent antibacterial activity against Escherichia coli strain. Compounds 7d, 7f, 7g, 7k, 7l, and 7m showed potent antibacterial activity against all bacterial strains. Compounds 7a, 7g, 7h, 7k, 7l, and 7m exhibited potent antifungal activity against all fungal strains. Furthermore, a molecular docking study revealed that compounds 7d, 7f, 7g, and 7k could bind to the active site of E. coli DNA gyrase subunit B protein and form hydrogen bonding with crucial amino acid residues Arg136 in the active sites. Comprehensively, our study recommends that 7d, 7f, 7g, and 7k could be a promising lead for developing more efficient antimicrobial drug candidates and DNA gyrase inhibitors.