LAUSR

Abstract In this research a series of pyranopyrazoles were efficiently synthesized via the one-pot four-component reactions of ethyl acetoacetate, hydrazinehydrate, aldehydes and malononitrile in the presence of Co3O4@SiO2-tNH2 nanocomposites as catalyst. This study offers many advantages including short reaction times, excellent yields, environmental friendly nature, simple purification techniques and economic availability of the catalyst. The structure and magnetic characteristics of the nanocatalyst were fully characterized by spectral techniques including TEM, FE-SEM, EDX, XRD, FT-IR and VSM analysis. The antibacterial and antifungal activities of pyranopyrazoles nanocomposite was investigated against gram positive, i.e., Staphylococcus aureus and methicillin resistance Staphylococcus aureus and gram negative bacteria i.e., Escherichia coli and Pseudomonas aeruginosa and candida albicans by disc diffusion and minimum inhibitory concentration (MIC) methods. The result of diameter of the observed inhibition zone and MIC showed that of derivatives synthesized, (4-Br), (4-F) and (2; 4-Cl) bromobenzaldehyde have the greatest effect on S. aureus.