Synthesis and Antibacterial Activities Evaluation of Chalconesemicarbazone Derivatives Bearing 1, 3, 4-Thiadiazole Moiety

A series of chalconesemicarbazone derivatives bearing a 1 ,3 , 4-thiadiazole moiety was designed and synthesized from benzaldehyde and 1 ,3 , 4-thiadiazole. All the target compounds were characterized by means of nuclear magnetic resonance and high resolution mass spectrometer. The preliminary bioassay results indicated that all the title compounds exhibited a certain antibacterial activities in vitro against Xanthomonas oryzae pv. oryzae, Ralstonia solanacearum and Xanthomonas axonopodis pv. citri. Especially, compounds 7j and 7k displayed excellent antibacterial activities (100%) against the above three plant pathogenic bacteria at a concentration of 100 mu g/ mL And the corresponding EC50 (50% effective concentration) values were 15. 13 , 30. 90 , 24. 49 and 21. 33 , 24. 54 , 14. 79 mu g/mL , respectively , which were superior to the commercial antibacterial agent bismerthiazol (92. 23 , 58. 88 and 123. 02 mu g/mL).