Biological activity of N4-tetradentate ligands and their copper(II) complexes

Abstract

Cancer has long been a global health concern and the recent resurgence of resistant microbial infections has led to the prediction that both of these issues will become the leading causes of death worldwide. As a result, there has been a push towards developing novel cytotoxic and antimicrobial agents. In this investigation, 14 different N4-Tetradentate Ligands (N4-TLs) and their respective copper(II) complexes were successfully synthesised and characterised. NMR and UV spectroscopy was used to characterise the ligands before coordination to copper(II). ESI-MS, UV spectrometry, and X-ray crystallography were used to characterise the copper(II) complexes, while CD spectroscopy was used to confirm chirality. The antimicrobial properties of the complexes were determined to be relatively poor in comparison with ampicillin and streptomycin, against S. aureus, K. pneumoniae and C. krusei microbial strains. However, several ligands and complexes demonstrated cancer potency with IC50 values comparable to cisplatin. QDNA binding studies revealed that Cu1 and Cu2 bound to QDNA at a ratio of 1:5 of metal complex to QDNA.

Date of Award	2018
Original language	English