Morphological and pharmacological investigation on some biopotent materials derived from substituted pyrimidine and imidazole enzyme constituents

•Substituted halopyrimidine derivatives are used in colorectal cancer chemotherapy.•5-Fluorouracil plays a crucial role in Food and Drug Administration systems.•The metal complexes show homogeneous morphology with microcrystalline environment.•Gel electrophoresis shows CT DNA undergoes oxidative cleavage with the complexes.•In vitro antimicrobial and antioxidant assessments show high inhibiting potential.

Coordinating behavior of novel N2O type mixed ligand complexes (1–6) have been synthesized from substituted fluoropyrimidine [5-Fluorouracil (5-FU; A)] with biopotent imidazole enzyme constituents (B) viz., imidazole(him) and benzimidazole(bim) in the presence of Ni(II), Cu(II) and Zn(II) ions. Synthesized complexes were characterized by chemical analysis, spectral studies, magnetic moment and conductivity measurements. The results of chemical analysis and the observed low molar conductance values propose their stoichiometry to be 1:1:1 (M:A:B) with non-electrolytic nature. From the spectral data, it is inferred that the ligands A & B coordinate with M(II) ions in bi and monodentate approach through C(4)O, N(3) and imidazole ring N(3) atoms respectively. The thermogravimetric analysis shows the dehydration, decomposition and thermal stability of mixed ligand complexes. XRD and SEM patterns show sharp crystalline peaks with homogeneous morphology. In vitro antimicrobial activities of free ligands (A & B) and their metal complexes were screened against some pathogenic strains by well diffusion technique. Absorption and gel electrophoresis experiments on the interaction of mixed ligand complexes with DNA suggest that all the complexes can bind as well as cleave the DNA by intercalation between chromophores and DNA base pairs. In addition, in vitro antioxidant activities were tested by DPPH free radical scavenging model.

Graphical abstractNovel N2O type mixed ligand complexes (1–6) have been synthesized from substituted fluoropyrimidine [5-Fluorouracil (5-FU: A)] with imidazole(him) and benzimidazole(bim) enzyme constituents(B) in the presence of M(II) ions [where M(II) = Ni(II), Cu(II) and Zn(II)]. Synthesized complexes (1–6) were characterized by chemical analysis and various spectral studies. In vitro antimicrobial activities of 5-Fluorouracil(A) and their mixed ligand complexes were screened against some bacterial and fungal strains by well diffusion technique. Electronic absorption and oxidative cleavage studies of the chelates with DNA under aerobic conditions show remarkable activities. Also, the absorption binding studies of CT DNA with the M(II)-5-FU(A)-him(B) complexes show decrease of 5–15% intensity with minor red shift along with significant hypochromicity and the free energy change values (Δ‡G) indicate the M(II) complexes can interact with DNA in a spontaneous manner.Figure optionsDownload full-size imageDownload as PowerPoint slide