Synthesis and bioactivities of 1-aryl-4-hydroxy-1H-pyrrol-2(5H)-one derivatives bearing 1,3,4-oxadiazole moiety

In this paper, a variety of 1-aryl-4-hydroxy-1 H -pyrrol-2(5 H )-one derivatives bearing 1,3,4-oxadiazole moiety were designed and synthesized. Preliminary bioassays suggested that these compounds not only exhibited favorable antibacterial activity toward plant pathogenic bacteria including Xanthomonas oryzae pv. oryzae ( Xoo ), Ralstonia solanacearum ( R. solanacearum ), and Xanthomonas axonopodis pv. citri. ( Xac ), but also demonstrated certain curative and protective activities against Tobacco mosaic virus (TMV). Further studies revealed that compounds 8a and 8l exerted the best inhibition effect against Xoo with the half-maximal effective concentration (EC 50 ) values of 8.6 and 7.3   μg/mL, respectively, which were better than that of commercial agricultural antibacterial bismerthiazol (EC 50   =   92.6   μg/mL). Given the above results, this kind of compounds can be further studied and explored as alternative antibacterial agents.