Summary: | The new zinc(II) complexes have been prepared in ethanol by condensation of 2-hydroxyacetophenone with either benzhydrazide or 3-methoxybenzhydrazide and zinc acetate in the presence of triethylamine. The IR, 1H, 13C NMR and UV-visible data show coordination of hydrazone ligands to the metal centers and the spectroscopic data augur well with the x-ray structures which had been published earlier. The Schiff bases and their complexes were screened for antimicrobial, cytotoxic and antioxidant activities. The anti-microbial activities of the ligands and complexes were evaluated by using plate diffusion method against some gram-positive bacteria, gram-negative bacteria and two fungi. There was growth inhibition exhibited by ligands and zinc(II) complexes against tested bacteria and fungi. The Schiff base, H 2hapbh was cytotoxic with IC 50 10-0 μgml -1 against the MCF-7 (human breast cancer cells) while both zinc(II) dimer complexes were strongly cytotoxic with IC 50 values of 4.5 μgml -1. The Schiff bases and zinc(II) complexes showed higher antioxidant activity than quercetin or vitamin E and is comparable with butylated hydroxytoluene (BHT), a commercially used synthetic antioxidant.
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