The synthesis of heterocyclic thiosemicarbazone derivatives and their transition metal chelates and evaluation of their biological activities

In this study, five thiosemicarbazone derivatives were synthesized. Firstly, cyclohexyl isothiocyanate was treated with hydrazine monohydrate in diethyl ether and cyclohexyl thiosemicarbazide was obtained. Then, this compound was reacted with 5-substituted-2-furaldehydes and converted to parent thiosemicarbazone derivatives. Finally, their iron (III), nickel (II) and cobalt (II) metal complexes were prepared in appropriate solvent medium.All reactions were monitored by Thin Layer Chromatography (TLC) Structures of synthesized compounds have been characterized by elemental analyses (C,H,N,S), UV-Vis, IR, 1H NMR and 13C NMR spectroscopies. The antibacterial activities of synthesized compounds were studied against Gram-positive bacteria: Staphylococcus aureus and Gram-negative bacteria: Klepsiella spp, Escherichia coli by using microdilution method and their minimum inhibition concentration (MIC) were detected.