Investigation of Antimicrobial, Antioxidant, and DNA Binding Studies of Bioactive Cu(II), Zn(II), Co(II), and Ni(II) Complexes of Pyrimidine Derivative Schiff Base Ligand

Abstract

A new pyrimidine based Schiff base ligand (HL) and its four complexes of type [MLOAc]⋅ H 2 O (Cu(II), 1; Zn(II), 2; Co(II), 3; and Ni(II), 4) have been synthesized and characterized by elemental analysis, MS, 1 H-NMR, FT-IR, UV-visible, and ESR techniques. The electronic and ESR spectral data suggested that complexes 1-4 possess square planar geometry. Antimicrobial activities of HL and complexes 1-4 were tested against four bacteria (Staphylococcus aureus, Staphylococcus pneumonia, Salmonella enterica typhi, and Haemophilus influenzae) and two fungal strains (Aspergillus flavus and Aspergillus niger). These results show that complexes 1-4 have good antimicrobial activity compared to HL. The DNA cleavage activity of HL and complexes 1-4 was monitored by the agarose gel electrophoresis method. The antioxidant property of the prepared compounds was assessed by using 2,2 -diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging method. DNA binding properties of HL and complexes 1-4 have been investigated by electronic absorption technique and viscometric measurements.

Experimental and theoretical studies on structural aspects of transition metal complexes of isonicotinoyl N‐oxide hydrazone: Their DNA‐binding interaction and cytotoxicity

“…The degree of hypochromism is also a paramount measure of intercalative binding strength. Further binding strength is generally evaluated by calculating the intrinsic binding constant K b by applying Wolfe–Shimmer equation 42,43 . The Kb values for all the systems under investigation have been calculated and presented in Table 5.…”

“…Further binding strength is generally evaluated by calculating the intrinsic binding constant K b by applying Wolfe-Shimmer equation. 42,43 The Kb values for all the systems under investigation have been calculated and presented in Table 5. The results obtained indicated an effectual intercalative mode of binding to DNA with affinity order for both ligand and complexes as Complexes…”

Anti-pathogenic Activity of Cu(II) Complexes Incorporating Schiff Bases: A Short Review

“…Antimicrobial activities of HL and the complexes were screened against the four different bacteria Staphylococcus aureus, Staphylococcus pneumonia, Salmonella enterica typhi and Haemophilus influenzae. Sparfloxacin was used as the standard antibacterial agent[30]. Schiff base ligand,(1-((2-hydroxynaphthalen-1-yl)methyleneamino)-2-thioxo-4-p-tolyl-1,2-dihydropyrimidin-5-yl)(p-tolyl)methanone (Hnafmmp) and its Ni(II), Pd(II), Pt(II), Cu(II), Co(II) complexes were prepared by Halime Güzin Aslan et al The Ligand and its complexes were evaluated for their in vitro antibacterial activity.…”

“…Proposed structure of complexes.The antifungal activities of ligand (HL) and complexes were screened against two different fungi, Aspergillus flavus (A. flavus) and Aspergillus niger (A. niger) strains & ketoconazole was used as standard drug[30]. The condensation product of 4-acetyl-3-methyl-1-phenylpyrazol-5-ones (mainly exists as the 3-methyl-1-phenyl-4-acetylpyrazolin-5-ol tautomer) with 1,2-diaminobenzene, and 2-aminophenol resulted in ONN-and ONO-type tridentate ligands & their transition metal complexes of VO(II), Cu(II), Fe(III), and Co(II) were synthesized by Ramasamy Jayarajan et al The complexes tested for antifungal activity against C. albicans, Rhizopus sp., and A. niger compared to the ligands and showed enhanced antifungal activity[45].…”