Novel 1,3,4-Oxadiazole Derivatives Containing a Cinnamic Acid Moiety as Potential Bactericide for Rice Bacterial Diseases

• Published in: International journal of molecular sciences Vol. 20; no. 5; p. 1020
• Main Authors: Wang, Shaobo, Gan, Xiuhai, Wang, Yanju, Li, Shaoyuan, Yi, Chongfen, Chen, Jixiang, He, Fangcheng, Yang, Yuyuan, Hu, Deyu, Song, Baoan
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 26.02.2019; MDPI
• Subjects: 1,3,4-oxadiazole derivatives; 3D-QSAR; Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - pharmacology; antibacterial activity; Bacteria; Bacterial diseases; Bactericides; Cinnamates - chemistry; Cinnamates - pharmacology; Cinnamic acid; Drug resistance; Fluorescence; Food security; Hydrogen Bonding; Hydrophobic and Hydrophilic Interactions; Leaf blight; Leaf streak; Leaves; Microbial Sensitivity Tests; Microorganisms; Oryza - microbiology; Oxadiazoles; Oxadiazoles - chemistry; Oxadiazoles - pharmacology; Pathogens; Pesticides; Plant Diseases - microbiology; Plant Leaves - drug effects; Plant Leaves - microbiology; Quantitative Structure-Activity Relationship; real-time quantitative PCR; Rice; Static Electricity; Xanthomonas - drug effects; antibacterial activity; bacterial diseases; 3D-QSAR; cinnamic acid; 1,3,4-oxadiazole derivatives; real-time quantitative PCR
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms20051020

Rice bacterial leaf blight and leaf streak are two important bacterial diseases of rice, which can result in yield loss. Currently, effective antimicrobials for rice bacterial diseases are still lacking. Thus, to develop highly effective and low-risk bactericides, 31 novel 1,3,4-oxadiazole derivatives containing a cinnamic acid moiety were designed and synthesized. Bioassay results demonstrated that all compounds exhibited good antibacterial activities in vitro. Significantly, compounds and showed excellent antibacterial activities against pv. ( ) and pv. ( ), with the 50% effective concentration (EC ) values of 0.58 and 0.34, and 0.44 and 0.20 μg/mL, respectively. These compounds were much better than thiodiazole copper (123.10 and 161.52 μg/mL) and bismerthiazol (85.66 and 110.96 μg/mL). Moreover, compound had better protective and curative activities against rice bacterial leaf blight and leaf streak than thiodiazole copper and bismerthiazol in vivo. Simultaneously, the in vivo efficacy of the compounds was demonstrated by real-time quantitative PCR to quantify bacterial titers. In addition, a three-dimensional quantitative structure⁻activity relationship model was created and presented good predictive ability. This work provides support for 1,3,4-oxadiazole derivatives containing a cinnamic acid moiety as a potential new bactericide for rice bacterial diseases.