Synthesis, characterization, crystal structure, and antimicrobial studies of novel thiourea derivative ligands and their platinum complexes

Abstract

N,N-Di-R-N′-(4-chlorobenzoyl)thiourea (Di-R: diethyl, di-n-propyl, di-n-butyl and diphenyl) ligands (HL1–4) and their Pt(II) complexes (cis-[Pt(L1–4-S,O)2]) have been synthesized and structurally characterized by elemental analyses, FT-IR and NMR spectroscopy. HL2 ligand and cis-[Pt(L4-S,O)2] metal complex have been also characterized by a single-crystal X-ray diffraction study. HL2, C14H19ClN2OS, crystallizes in the monoclinic space group P21/n (no. 14), with Z = 4, and unit cell parameters, a = 11.1405(16) Å, b = 9.7015(12) Å, c = 14.790(2) Å, β = 106.547(7)°. The cis-[Pt(L4-S,O)2], C40H28Cl2N4O2PtS2: triclinic, space group P-1 (no. 2), a = 8.9919(3) Å, b = 14.7159(6) Å, c = 15.7954(6) Å, α = 113.9317(18)°, β = 97.4490(18)°, and γ = 105.0492(16)°. Single crystal analysis of complex, cis-[Pt(L1–4-S,O)2], revealed that a square planar coordination geometry is formed around the platinum atom by two sulfur and two oxygen atoms of the related ligands, which are in a cis configuration. In addition, the thiourea derivative ligands and their complexes were evaluated for both their in-vitro antibacterial and antifungal activity. The results have been reported, explained, and compared with fluconazole and ampicillin, used as reference drugs.