Synthesis and Antibacterial Evaluation of Novel 1,3,4-Oxadiazole Derivatives Containing Sulfonate/Carboxylate Moiety.

bstract: In order to discover new lead compounds with high antibacterial activity, a series of new derivatives were designed and synthesized by introducing a sulfonate or carboxylate moiety into the 1,3,4-oxadiazole structure. Antibacterial activity against two phytopathogens, pv. and pv. , was assayed in vitro. The preliminary results indicated that ten compounds including - and - had good antibacterial activity against , with EC values ranging from 50.1-112.5 M, which was better than those of Bismerthiazol (253.5 M) and Thiodiazole copper (467.4 M). Meanwhile, , , and demonstrated good inhibitory effect against with EC values around 95.8-155.2 M which were better than those of bismerthiazol (274.3 M) and thiodiazole copper (406.3 M). In addition, in vivo protection activity of compound and against rice bacterial leaf blight was 68.6% and 62.3%, respectively, which were better than bismerthiazol (49.6%) and thiodiazole copper (42.2%). Curative activity of compound and against rice bacterial leaf blight was 62.3% and 56.0%, which were better than bismerthiazol (42.9%) and thiodiazole copper (36.1%). Through scanning electron microscopy (SEM) analysis, it was observed that compound caused the cell membrane of pv. ruptured or deformed. The present results indicated novel derivatives of 5-phenyl sulfonate methyl 1,3,4-oxadiazole might be potential antibacterial agents.