Synthesis, Characterization and Biological Evaluation of Some Cobalt (II), Nickel (II) and Copper (II) Complexes of 4[N(2’,4’-Dichlorobenzalidene) Amino]Thiosemicarbazone and 4[N(2’,4’Dinitrobenzalidene) Amino] Thiosemicarbazone

Of the sulphur donor ligands, thiosemicarbazones have perhaps not been given as much attention as dithiophosphate, dithiocarbamates, dithiolates, dithio--diketonates, dithiooxamide or xanthates. Although many thiosemicarbazones possess a wide spectrum of medicinal properties including activity against influenza, protozoa, small pox, certain kinds of tumour, tuberculosis, leprosy, bacterial and viral infections, psoriasis,, rheumatism and tripamosomiasis, cocidiosis, malaria and have been suggested as possible pesticides and fungicides. Their activity has frequently been thought to be due to their ability to chelate trace metals. In recent years a number of review articles have been appeared on various metal-coordination complexes of thiosemicarbazones. In research of new thiosemicarbazones, two new thiosemicarbazones i.e., 4[N-(2',4'-dichlorobenzalidene)amino]antipyrine thiosemicarbazone (DCBAAPTS) and 4[N- (2',4'-dinitrobenzalidene)amino]antipyrine thiosemicarbazone (DNBAAPTS) have been synthesized and characterized. The complexing abilities of both thiosemicarbazones toward cobalt(II), nickel(II) and copper(II) metal salts have been explored. The newly synthesized complexes have the general composition [M(L)·H₂O·X₂] (M = Co ,Ni or Cu; X = Cl, Br, NO₃, NCS or CH₃COO; L = DCBAAPTS or DNBAAPTS). All the complexes were characterized by elemental analyses, molar mass, molar conductance, magnetic susceptibility, infrared and electronic spectra. These metal complexes were screened for their antibacterial and antifungal activities on different species of pathogens, fungi and bacteria and their biopotency has been discussed.