The treatment of N-Phenylmorpholine-4-carbothioamide (HPMCT) with bivalent metal ions in a 2:1 mol ratio without a base present affords [MCl₂(κ¹S-HPMCT)₂] {M = Cu(1), Pd(2), Pt(3), and Hg(4)} in a good yield. Furthermore, the reaction of two equivalents of HPMCT and one equivalent of bivalent metal ions in the presence of Et₃N has afforded [M(κ²S,N-PMCT)₂] {M = Ni(5), Cu(6), Pd(7), Pt(8), Zn(9), Cd(10), and Hg(11)}. Infrared, ¹H, ¹³C Nuclear Magnetic Resonance molar conductivity, and elemental analysis were used to characterize the synthesized complexes. The results suggest that HPMCT is bonded as monodentate via an S atom in Complexes (1–4), whereas linkage as a bidentate chelating ligand via S and N atoms gives two chelate rings. Moreover, the synthesized ligand and the complexes were screened for antibacterial activity, which displayed that the very best antibacterial activities for Complexes (1), (6), and (3). In addition, the cytotoxic activity of the HPMCT ligand, [PdCl₂(HPMCT)₂] (2), and [PtCl₂(HPMCT)₂] (3) were screened on breast cancer cell lines (MCF-7), and Complex (3) reveals the most promising activity with an IC₅₀ value 12.72 ± 0.4 μM. Using the B3LYP method and 6-311++G(d,p) basis sets for the ligand and the SDD basis set for the central metal, the synthesized complexes utilizing the prepared ligand were optimized. Various quantum parameters such as hardness, electron affinity, dipole moment, vibrational frequencies, and ionization energy for the ligand and its complexes have been calculated. In general, a favorable agreement was found between the experimental results and the obtained theoretical results.

Mixed ligand complexes of Pd(II) and Cd(II) with N-picolyl-amine dithiocarbamate (PAC-dtc) as primary ligand and tertiary phosphine ligand as secondary ligands have been synthesized and characterized via elemental analysis, molar conductance, NMR (¹H and ³¹P), and IR techniques. The PAC-dtc ligand displayed in a monodentate fashion via sulfur atom whereas diphosphine ligands coordinated as a bidentate mode to afford a square planner around the Pd(II) ion or tetrahedral around the Cd(II) ion. Except for complexes [Cd(PAC-dtc)₂(dppe)] and [Cd(PAC-dtc)₂(PPh₃)₂], the prepared complexes showed significant antimicrobial activity when evaluated against Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans and Aspergillus niger. Moreover, DFT calculations were performed to investigate three complexes {[Pd(PAC-dtc)₂(dppe)](1), [Cd(PAC-dtc)₂(dppe)](2), [Cd(PAC-dtc)₂(PPh₃)₂](7)}, and their quantum parameters were evaluated using the Gaussian 09 program at the B3LYP/Lanl2dz theoretical level. The optimized structures of the three complexes were square planar and tetrahedral geometry. The calculated bond lengths and bond angles showed a slightly distorted tetrahedral geometry for [Cd(PAC-dtc)₂(dppe)](2) compared to [Cd(PAC-dtc)₂(PPh₃)₂](7) due to the ring constrain in the dppe ligand. Moreover, the [Pd(PAC-dtc)₂(dppe)](1) complex showed higher stability compared to Cd(2) and Cd(7) complexes which can be attributed to the higher back-donation of Pd(1) complex.