Synthesis and Characterization of Biopotent Transition Metal Complexes of Schiff Base 2-{(1)-1-[2-(1,3-Benzothiazol-2-yl)hydrazinylidene]ethyl}-6,10b-dihydro-3H-benzo[f]chromen-3-one and their Biological Evaluation

Three transition metal(II) complexes (M = Co/ Zn/Pd) were synthesized by using a newly synthesized Schiff base ligand 2-{(1E)-1-[2-(1,3-benzothiazol-2-yl)hydrazinylidene]ethyl}-6,10b-dihydro-3H-benzo[f]chromen-3-one (L) by conventional method. The structure of the compounds were determined by physical and analytical techniques like UV-visible, FT-IR, 1H and 13C NMR and mass spectroscopic techniques and the crystallinity and inter-planar distance of the complexes were confirmed by XRD. The electron density in HOMO and LUMO was determined by DFT studies. The studies of electronic spectra and measurements of magnetic susceptibility suggest that Co(II) complex shows an octahedral geometry, Pd(II) complexes show square planar geometry and (ZnL2Cl2) complex shows tetrahedral geometry. The molar conductivity results suggested the non-electrolytic nature of the metal(II) complexes. The synthesized compounds was tested against antibacterial activity for Gram-positive and Gram-negative bacteria. The molecular docking study demonstrated that the ligand and its metal(II) complexes possess antibacterial and anticancer properties, and the results showed that the compounds were effective against the microorganisms that were examined. Furthermore, the results found that metal(II) complexes provided enhanced immunity against cancer cell lines.