Template synthesis, characterization, in vitro antimicrobial, and DNA cleavage studies of Co(II), Ni(II), Cu(II), and Zn(II) complexes with 15-membered N₂O₂ diazadioxa macrocycles

Abstract

A novel series of 15-membered diazadioxa macrocyclic complexes [MLCl₂] (M˭Co(II), Ni(II), Cu(II), and Zn(II) ) have been synthesized via the condensation reaction of salicylaldehyde and 1,2-dibromoethane with a 3-subtituted-4-amino-5-hydrazino-1,2,4-triazole in the presence of transition metal ions as templates in ethanol. The mode of bonding and overall geometry of the complexes have been inferred through IR, ¹H NMR, ¹³C NMR, EPR, electronic spectral studies, conductivity, magnetic, thermal, and electrochemical studies. All the complexes are soluble in DMF and DMSO and are non-electrolytes. All these complexes have been screened for their antibacterial (Escherichia coli, Staphylococus aureus, Salmonella typhi, Pseudomonas aeruginosa) and antifungal activities (Aspergillus niger, Aspergillus flavus, and Cladosporium) by the minimum inhibitory concentration method. The DNA cleavage is studied by agarose gel electrophoresis. An octahedral geometry is proposed for all the complexes.

Keywords:

• synthesis
• triazole
• electrochemistry
• macrocycle
• biologically activity

Acknowledgements

The authors are grateful to the Chairman, Department of Chemistry, Karnatak University, Dharwad for the facilities. One of the authors (U.V.K.) conveys his gratitude to the University Grant Commission, NewDelhi, for grant of Research Fellowship in Science for Meritorious students.