Synthesis, Antibacterial and Antileishmanial Activity, Cytotoxicity, and Molecular Docking of New Heteroleptic Copper(I) Complexes with Thiourea Ligands and Triphenylphosphine

Abstract

A series of copper(I) complexes with triphenylphosphine and N-acyl-N′-arylthioureas were synthesized and characterized by elemental analysis and IR and NMR (¹H, ¹³C, ³¹P) spectroscopy. The thiourea ligands and their copper(I) triphenylphosphine complexes were screened for antibacterial and antileishmanial activities and cytotoxicity. The synthesized compounds showed much better activity as compared to glucantime and Kanamycin used as reference drugs. The thiourea ligands showed better activity than their Cu(I) complexes. The molecular docking technique was utilized to ascertain the mechanism of action toward molecular targets (GP63 and 16S-rRNA A-site). It was found that the ligands and complexes were stabilized at the active site by electrostatic and hydrophobic forces, consistent with the corresponding experimental results. The in silico study of the binding pattern predicted that one of the synthesized ligands, N-(5-chloro-2-nitrophenyl)-N′- pentanoylthiourea, can serve as a potential surrogate for hit-to-lead generation and design of novel antibacterial and antileishmanial agents.