D. Nasrin el al / Chemistry Journal (2013), Vol. 03, Issue 01, pp. 13-19 ISSN 2049-954X Available online at www.scientific-journals.co.uk 13 Synthesis, Characterization and Antimicrobial Activity of Metal Complexes of Schiff’s Base Derived from S- benzyldithiocarbazate with 2-hydroxyacetophenone D. Nasrin 1 *, M. Ashraful Alam 2 , M. Nazmul Hossain 3 and M. Nazimuddin 2 1 Department of Chemistry, Bangladesh University of Engineering & Technology (BUET), Dhaka-1000, Bangladesh 2 Department of Chemistry, University of Chittagong, Chittagong, Bangladesh 3 Department of Biochemistry & Molecular Biology, University of Chittagong, Bangladesh Mobile No: (+880)1556399694 *E-Mail: dina@chem.buet.ac.bd Abstract Structural modification of organic molecule has considerable biological relevance. Further, coordination of a biomolecules to the metal ions significantly alters the effectiveness of the biomolecules. In view of the antimicrobial activity a series of nickel, copper and zinc complexes of tridentate Schiff base derived from the condensation reaction of S-benzyldithiocarba- zate with 2- hydroxyacetophenone have been synthesized and found to be potential antimicrobial agents. An attempt is also made to correlate the biological activities with geometry of the complexes. The complexes have been characterized by molar conductance, magnetic susceptibility, IR and electronic spectroscopic techniques. Keywords: Schiff Base, S-benzyldithiocarbazate, Complexes, Antimicrobial Activity 1. Introduction In general, bacteria have the genetic ability to send and acquire resistance to drugs, which are used as therapeutic agents. Even if pharmaceutical industries produce a lot of new antibiotics in the last three decades, the resistance of microorganisms to these drugs has increased (Faúndez et al, 2004). The microbial resistance represents a problem and the outlook for the use of antimicrobial drugs in the future is still uncertain. Therefore, it must be taken measures to reduce this problem, for example, to control the use of antibiotic, develop research to better understand the genetic mechanisms of resistance, and to continue studies to develop new drugs, either synthetic or natural. The ultimate goal is to offer appropriate and efficient antimicrobial drugs to the patient (Kabbani et al, 2007). Metal complexes may be subjected for the design and synthesis of such possibilities having such biological activities (Chohan & Supuran, 2005; Altundas et al, 2010 and Singh et al, 2010). The chemistry of Schiff bases and their structural analogues has occupied a place of considerable importance (Garnovskii et al, 2009) as they easily form stable complexes with most transition metal ions and well-established biological properties (Illán- Cabeza et al, 2005 and Heshmatpour et al, 2007). Sulphur-nitrogen chelating agents, especially the thiosemi- carbazones and their metal complexes posses a range of biological applications that include antitumour (Antholine et al, 1977), antifungal (Mital et al, 1981), antiviral (Shipman et al, 1981), antibacterial (Dobek et al, 1980), antifilarial (Klayman et al, 1991) and antimalarial activiti- es (Klayman et al, 1979). Thiosemcarbazones exercise their biological activity in mammalian cells by inhibiting ribounucleotide reductases- a necessary enzyme in the synthesis of DNA precursors (French et al, 1970). The non-heme subunit of the enzyme has been shown to be Research Paper