Synthesis, characterization, thermal, anticancer studies, and density functional theory for potentially active pyrimidine‐based complexes

Abstract

This work aimed to create and characterize some new bioactive chelates of bis azodye ligand, 5‐((2‐hydroxy‐4,6‐dioxo‐1,4,5,6‐tetrahydropyrimidin‐5‐yl)diazenyl)naphthalen‐1‐yl)diazenyl) pyrimidine 2,4,6 (1H,3H,5H)‐trione. Except for the Sm(III) chelate, which exhibited a (3M:1L) molar ratio, all chelates had a (2M:1L) stoichiometry. According to Fourier transform infrared spectroscopy (FT‐IR), azo groups were not included in chelating with all ions except Sm(III), where just one azo group was coordinated. With the Ni(II) and Zn(II) ions, the ligand behaved as OON‐tridentate moiety; with the Co(II) and Cu(II) ions, it behaved as ON‐bidentate moiety. Co(II) and Cu(II) chelates had square planar structure, and Ni(II) and Zn(II) chelates had square pyramidal geometry. The chelates had greater thermal stability than the uncoordinated ligand due to the chelate's structure. [Sm3(H4L)(OH)7(NO3)2.H2O].4.5EtOH exhibited the maximum thermal stability, which may be due to the large number of solvent molecules and the high number of chelate rings. With the exception of the Sm(III) chelate, all of the examined chelates were more cytotoxic against MCF‐7 and Hep‐G2 cells than their parent ligand. With the exception of the Zn(II) chelate, which demonstrated activity on Hep‐G2 rather than MCF‐7, the effects of each metal chelate on the two cells were nearly equivalent. All of the studied chelates, especially Zn(II) and Co(II), were potent as antioxidants more than the native ligand. To support experimental findings, density functional theory (DFT) studies were performed via the CAM‐B3LYP/LanL2DZ method, and the geometry of the ligand and its chelates had been validated.