Synthesis and in vitro antibacterial evaluation of some thiosemicarbazides and thiosemicarbazones

In the present study various thiosemicarbazides and thiosemicarbazones were synthesized and screened for their antimicrobial activity. Among the ligands tested, compounds 1, 3, 4 and 5 demonstrated inhibitory effects at 0.4 - 0.5 μM concentrations against E. coli while 1-(4-fluorobenzoyl)-N4-ethyl-thiosemicar-bazide (3) demonstrated the maximum inhibitory effective compound against E. coli, also possessing high water solubility. Instead, compound 3 demonstrated weak antibiotic effects against S. aurous while compounds 4 - 6 demonstrated significant antibacterial effects at 0.4 - 0.42 μM against the latter organism. Chloramphenicol was used as the positive control.