Solvent-dependent crystallization and anti-cancer activities based on Ni(II) and Co(II) complexes of 1-picolinoyl-4-phenyl-3-thiosemicarbazide: Synthesis, crystal structure, and photoluminescence study

Abstract

In search of alternative of platinum-based drugs for the treatment of cancer, lead to the development of other potential metallodrug of transition metal complexes. The efficacious and novel experimental content of this paper reports the synthesis of [Ni(Hppts)2].CHCl3 (1a), [Ni(Hppts)2].(CH3)2SO (1b) and [Co(Hppts)2] (2) complexes of 1-picolinoyl-4-phenyl-3-thiosemicarbazide (H2ppts). The synthesized complexes have been characterized by UV-vis., Infrared, and NMR spectrometry. Furthermore, complexes 1a and 1b were characterized by single-crystal X-ray diffraction data. Emission spectra show that, complex 1a exhibits higher fluorescence intensity as compared to that of ligand H2ppts and complex 2. The order of fluorescence intensity was found as complex 1a > complex 2 > H2ppts. Moreover, Complexes 1a and 1b are stabilized via various types of intermolecular interactions. The cytotoxicity of complexes 1a, 2, and ligand was evaluated against Dalton's Lymphoma cells using standard MTT Assay. The anticancer activity results showed that complex 1a significantly reduced cell viability in a dose-dependent manner, whereas H2ppts and complex 2 did not show significant reduction in cell viability of DL cells when compared with the control. The complex 1a IC50 value was determined to be around 40 µg/mL. The anti-tumor activity concludes that the complex 1a has high anti-neoplastic activity on DL cells at low doses.