New bioactive ferrocene-substituted heteroleptic copper(I) complex: Synthesis, structural elucidation, DNA interaction, and DFT study

In the present work, a new para-ferrocenylbenzoate copper(I) complex (a4) has been synthesized and characterized by numerous spectroscopic techniques such as: FT-IR, AAS, and CHNS analysis. Moreover, the single-crystal X-ray structure of the compound a4 was also explored. The DNA binding potency was determined by cyclic voltammetry, UV-visible spectroscopy, and viscometry. The redox behavior of the complex studied by cyclic voltammetry revealed a single quasi-reversible voltammogram, attributed to the dominant redox-active ferrocenyl moiety. The electrochemical study reveals that the complex binds to DNA non-covalently, the mode of interaction in particular, was found to be an electrostatic. The DNA binding constant was found to be 4.3 × 104 M−1, which is very significant and impressive for non-covalent interactions, and is in close agreement with the UV-visible spectroscopic results. DFT/B3LYP method was used to ascertain the energies of frontier molecular orbitals (HOMO/LUMO) and the charge distribution on the molecular structure. The ferrocene-based copper(I) complex (a4) demonstrated to be a decent candidate in terms of cytotoxicity, although less active than that of the standard chemotherapeutic drug (cisplatin).