New Silver(I) Complex Based on Thiocarbamoyl-naphthylpyrazoline-1,3,5-Trisubstituted Ligand

Pyrazoline derivatives are notable for their various pharmacological properties, especially in anticancer and antioxidant activities.  This study details the synthesis and characterization of three novel silver(I) complexes with pyrazoline ligands. Single-crystal X-ray diffraction confirmed the silver(I) complex has the formula [Ag(SCN)(L2)]. The metal center shows a distorted tetrahedral geometry, indicated by a τ4 parameter of 0.866. The silver(I) atom participates in intermolecular Ag···S interactions, influencing the crystal packing. Spectroscopic studies in the ultraviolet-visible region reveal a strong similarity between the ligands and the complexes, with no significant shifts and a hyperchromic effect following coordination. The bands can be attributed to ligand-centered interligand (IL) transitions and to IL transitions, along with ligand-to-metal charge transfer (LMCT) transitions, in the complexes. Biological assays indicate that the silver(I) complexes possess enhanced antibacterial activity compared to their uncoordinated ligands, suggesting their promise as new antimicrobial agents.