Antimicrobial and DNA-Cleavage Studies of 22-Membered N₄ Tetraaza Macrocyclic Triazoles: Template Synthesis and Physicochemical Characterization

Abstract

A novel series of 22-membered macrocyclic complexes of the type [MLCl₂] (M˭Co²⁺, Ni²⁺ and Cu²⁺) have been synthesized with newly derived biologically active ligands (L¹–L^IV). These ligands were synthesized by the condensation of ortho-phthalaldehyde and bis-(4-amino-5-mercapto-1, 2, 4-triazole-3-yl)alkanes. The mode of bonding and overall geometry of the complexes have been inferred through IR, EPR, electronic spectral studies, conductivity, magnetic, thermal, and electrochemical studies. 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 minimal inhibitory concentration (MIC) method. The DNA cleavage study was done by agarose gel electrophoresis technique.

Keywords:

• Synthesis
• complex
• macrocyclic
• bistriazole
• ortho-phthalaldehyde

Acknowledgments

The authors are grateful to the Chairman, Department of Chemistry, Karnatak University, Dharwad for the facilities. U. V. K. is grateful to the University Grant Commission, New Delhi for the grant of Research Fellowship in Science for Meritorious Students.