New bioactive Cu(I) thiourea derivatives with triphenylphosphine; synthesis, structure and molecular docking studies

The synthesized thioureas, 1-(3-fluorobenzoyl))-3-(4-(diethyl aminophenyl) thiourea (I₁), 1-benzoyl-3-(2-chlorophenyl) thiourea (I₂) and 1-(2-fluorobenzoyl)-3-(2-chlorophenyl) thiourea (I₃) along with triphenylphosphine were reacted with Cu(I) chloride in mole ratios 1:2:1 by using dry acetone as solvent under nitrogen to get 1–3. The synthesized thioureas and metal derivatives were characterized by spectroscopic techniques such as IR and multinuclear (¹H, ¹³C) NMR. Compound 3 is analyzed by single crystal X-ray analysis and data reveal that the Cu is four coordinate having tetrahedral molecular geometry. The interaction of 1–3 with DNA is ascertained by cyclic voltammetry, determining binding constant, binding energy and diffusion coefficient. The findings suggest that the complexes interact with DNA in an electrostatic mode. The antioxidant activity data show that 3 has the highest free radical scavenging ability having Ic₅₀ value of 10 µg/mL. The synthesized compounds were also screened against various bacterial strains and found some encouraging results. The binding interactions of the metal complexes with a specific protein were further validated by molecular docking studies and the results obtained show their strong interaction with amino acid residue in the binding pocket of the target protein.