Novel sulfone derivatives containing a 1,3,4‐oxadiazole moiety: design and synthesis based on the 3D‐QSAR model as potential antibacterial agent

Abstract

BACKGROUNDThe rice bacterial leaf blight (BLB) is one of the most serious bacterial diseases caused by Xanthomonas oryzae pv. oryzae (Xoo), which can cause yield loss of rice up to 50%. The three‐dimensional quantitative structure–activity relationship (3D‐QSAR) is an important auxiliary method to find potential high‐efficient pesticides active structures.RESULTSA series of novel 1,3,4‐oxadiazole compounds were designed and synthesized based on the 3D‐QSAR model, and their antibacterial activities in vitro against Xoo were evaluated. The results indicated that all the target compounds showed excellent in vitro antibacterial activities. For example, the compounds 6, 12, 13, 20, 21, and 23 exhibited excellent antibacterial activities against Xoo, with half‐maximal effective concentration (EC50) values of 0.24, 0.31, 0.36, 0.29, 0.19, and 0.31 mg/L, respectively, which were superior to the antibacterial agents thiodiazole copper (127.44 mg/L) and bismerthiazol (91.08 mg/L). Meanwhile, compound 21 showed good antibacterial activity in vivo against BLB, with curative and protective activities of 46.7% and 56.4%, respectively, which were superior to thiodiazole copper (28.5% and 32.5%) and bismerthiazol (37.6% and 38.4%). Compound 21 can significantly reduce the extracellular polysaccharides production of Xoo, increase the permeability of the cell membranes, and also can cause cell surface wrinkles, deformation and dryness.CONCLUSIONThe 3D‐QSAR model can be used to find sulfone compounds containing a 1,3,4‐oxadiazole moiety with higher antibacterial activity, and compound 21 can be used as a potential antibacterial agent in the future. © 2020 Society of Chemical Industry

Design, Synthesis and in Vitro Antifungal Mechanism of Novel Phenylalanine Derivatives

“…The residue was purified by column chromatography on silica gel (eluent: dichloromethane/methanol = 100/1) to obtain E as a yellow oil, with the yield of 60 %. General Synthetic Procedure for Intermediate F n (take F 7 as a Sample) [33,34] Intermediate E (0.01 mol) and K General Synthesis Procedure for Target Compounds G 1 -G 28 [35] Intermediate F n was dissolved in dichloromethane and stirred with trifluoroacetic acid for 4 h at r.t. Saturated sodium carbonate solution was added to adjust the pH to 7 -8.…”

Design and synthesis novel amide derivatives containing an 1,3,4‐oxadiazole moiety as potential antibacterial agents

“…Xoo, Xanthomonas oryzae pv. oryzae added to stir for 3-12 h at room temperature [12]. The target compounds 1-25 were obtained with a yield of 45%-67% by recrystallization and chromatography column.…”

“…The 1,3,4‐oxadiazole derivatives with a wide range of agricultural biological activity were used to discover new pesticides, such as insecticides [11], antibacterial agents [12], nematicides [13,14], herbicides [15], antiviral agents [16], and fungicides [17]. In our previous work, an 1,3,4‐oxadiazole candidate antibacterial agent (jiahuangxianjunzuo [JHXJZ]) was synthesized with excellent antibacterial activities [18].…”

Design, synthesis, and bioactivity of ferulic acid derivatives containing an β-amino alcohol

“…Plant pathogenic bacteria include Xanthomonas oryzae pv. oryzae (Xoo) , which causes rice bacterial blight with crop yield loss of up to 50% [ 5 , 6 ], and Xanthomonas axonopodis pv . citri (Xac) , which causes citrus canker [ 7 ].…”