Synergistic Phosphorus(V)‐Ferrocene Hydrazone Metal(II) Complexes: Synthesis, Characterization, Bioactivity, DNA Interaction, and Molecular Docking Insights
Maniyammai Subbaiah, Aishwaryalakshmi M., Kiran K. Mandrekar, Jayalakshmi M., Senthil A. Gurusamy ThangaveluABSTRACT
A new structure of acyclic P(V) dihydrazone Schiff base ligand, phenylphosphonothioic ferrocene dihydrazone (S = P(Ph)‐[NH‐N = CH‐C 5 H 4 FeC 5 H 5 ] 2 , PPFD) was designed and synthesized by substitution of P(V) dichloride (S = P(Ph)‐Cl 2 ) using hydrazine hydrate (N 2 H 4 .H 2 O) followed by condensation of (S = P(Ph)‐[NH‐NH 2 ] 2 , PPDH) with two equivalents of ferrocene carboxaldehyde (Fc‐CHO). P(V) dihydrazone, PPFD with multisite coordination center was explored as potential ligand to form a series of transition metal(II) complexes of Co(II), Ni(II), Cu(II), and Zn(II) coordinated with the Schiff base. PPFD and respective PPFD‐metal(II) complexes were characterized by spectral and analytical methods, UV–vis, FTIR, 1 H, 13 C and 31 P NMR, ESI‐MS, and MALDI‐TOF. As compared to free ligand, metal(II) complex manifested its better antibacterial activity. By using Ni(II) complex solution (200 µM), identified the inhibition of 91.4% against Staphylococcus aureus to evaluate antibacterial activity, whereas Cu(II) complex showed inhibition upto 89.6% against Escherichia coli . Agar well diffusion and broth dilution techniques were used to assess the antibacterial properties of ligand and metal(II) complexes. Gel electrophoresis was performed to examine the DNA cleavage of samples to authenticate tendency to interact with genetic material. Binding interactions of these samples with calf thymus (CT‐DNA), COX2, and VEGFR2 proteins were investigated from cyclic voltammetry, optical absorption titration, and molecular docking.