Abstract A series of 4-(substituted benzylidene-amino)-1, 5-dimethyl-2-phenyl-1, 2- dihydropyrazol-3-ones (1–17) was synthesized and tested in vitro for its antimicrobial and anticancer potentials. The biological screening results indicated that compounds having m- chloro substituent on benzaldehyde portion showed antimicrobial potential, whereas compounds having chloro, methoxy, and hydroxyl groups showed anticancer potential. ...