Synthesis, antimicrobial and antioxidant activities of some 5-pyrazolone based Schiff bases

A series of nine new biologically active Schiff bases 5a–i were synthesized by a condensation of 4-acyl-5-pyrazolones 3a–c with aromatic diamines 4a–d, and characterized by elemental analysis, mass and spectroscopic data. All the compounds showed antibacterial activity against Bacillus subtilis and Escherichia coli, good antifungal activity against Phytophthora infestanse and Aspergillus niger, and ferric-reducing antioxidant power (FRAP).