Antibacterial and Antiviral Activities of 1,3,4-Oxadiazole Thioether 4<i>H</i>-Chromen-4-one Derivatives

Abstract

Various 1,3,4-oxadiazole thioether 4<i>H</i>-chromen-4-one derivatives were conceived. The title compounds demonstrated striking inhibitory effects against <i>Xac</i>, <i>Psa</i>, and <i>Xoo</i>. EC₅₀ data exhibited that <b>A8</b> (19.7 μg/mL) had better antibacterial activity against <i>Xoo</i> than myricetin, BT, and TC. Simultaneously, the mechanism of action of <b>A8</b> had been verified by SEM. The results of anti-tobacco mosaic virus indicated that <b>A9</b> had the best <i>in vivo</i> antiviral effect compared with ningnanmycin. From the data of MST, it could be seen that <b>A9</b> (0.003 ± 0.001 μmol/L) exhibited a strong binding capacity, which was far superior to ningnanmycin (2.726 ± 1.301 μmol/L). This study shows that the 1,3,4-oxadiazole thioether 4<i>H</i>-chromen-4-one derivatives may become agricultural drugs with great potential.