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

ABSTRACT: Abstract: 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, Xanthomonas oryzae pv. oryzae (Xoo) and Xanthomonas axonopodis pv. citri(Xac), was assayed in vitro. The preliminary results indicated that ten compounds including 4a-1-4a-4 and 4a-11-4a-16 had good antibacterial activity against Xoo, with EC50 values ranging from 50.1-112.5 µM, which was better than those of Bismerthiazol (253.5 µM) and Thiodiazole copper (467.4 µM). Meanwhile, 4a-1, 4a-2, 4a-3 and 4a-4 demonstrated good inhibitory effect against Xanthomonasaxonopodis pv. citri with EC50 values around 95.8-155.2 µM which were better than those of bismerthiazol (274.3 µM) and thiodiazole copper (406.3 µM). In addition, in vivo protection activity of compound 4a-2 and 4a-3 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 4a-2 and 4a-3 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 4a-2 caused the cell membrane of Xanthomonas oryzae pv. oryzae ruptured or deformed. The present results indicated novel derivatives of 5-phenyl sulfonate methyl 1,3,4-oxadiazole might be potential antibacterial agents.

SUBMITTER: Wang L 

PROVIDER: S-EPMC7180883 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature