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Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/67584

#### Abstract

The increase of death rate, associated with infectious diseases, is directly linked to the bacteria that have multiple resistance to antibiotics. The lack of efficient medical treatment is the main cause of this problem. The synthesis of new antibacterial agents, through various methods, is, for sure, an emergency medical issue. Recent research focuses more and more on the synthesis of complexes of the transitional metals with ligands of Schiff-base type, as a result of the biological properties which they have. This article presents the synthesis of several complexes with base Schiff ligands, derived from 4-aminoantipyrine and in vitro research of their antibacterial activities. The new compounds were tested for their in vitro antibacterial activity against Staphylococcus aureus var. Oxford 6538, Klebsiella pneumoniae ATCC 100131, Escherichia coli ATCC 10536, and Pseudomonas aeruginosa ATCC 9027 strains. Based on the "in vitro" studies, we can say that ten of the complexes synthetized can be successfully used instead of streptomycin, where there is resistance to this antibiotic.

Keywords: 4-aminoantipyrine, Schiff bases, metal complexes, antibacterial agents, streptomycin
