α-Haloacetophenone and analogues as potential antibacterial agents and nematicides.

A series of α-haloacetophenones and analogues were synthesized. The bioassays show that some target compounds have good antibacterial activity against Xanthomonas oryzae pv. oryzae (Xoo), Xanthomonas axonopodis pv. citri (Xac) and Meloidogyne incognita (M. incognita). Especially, the compound 24 has good in vitro and in vivo antibacterial activities against Xoo, the EC50 value, curative and protection activities are 0.09 mg/L, 48.9%, and 52.3%, respectively, which are better than the thiodiazole copper and bismerthiazol. Meanwhile, the compound 24 has good in vitro antibacterial activity against Xac, and has an EC50 value of 1.6 mg/L. Moreover, the compound 19 exhibits good nematicidal activity M. incognita, with the LC50 value of 1.0 mg/L, which is better than the positive control avermectin. In addition, the compound 24 can inhibit the formation of extracellular polysaccharide and biofilm of Xoo, and change the permeability of cell membrane. α-haloacetophenone and analogues have the advantages of simple structure, high efficiency, broad spectrum of biological activity, and can be used as antibacterial agents and nematicides or lead compounds in the future.