Rational Optimization and Action Mechanism of Novel Imidazole (or Imidazolium)-Labeled 1,3,4-Oxadiazole Thioethers as Promising Antibacterial Agents against Plant Bacterial Diseases

• DOI: 10.1021/acs.jafc.8b06242
• Publication Date: 2019-03-05T16:51:58Z
• Authors: Pei-Yi Wang; Ming-Wei Wang; Dan Zeng; Meng Xiang; Jia-Rui Rao; Qing-Qing Liu; Li-Wei Liu; Zhi-Bing Wu; Zhong Li; Bao-An Song; Song Yang
• Keywords: Imidazole; Moiety; Oxadiazole; EC50; Ralstonia solanacearum

The emergence and widespread occurrence of plant bacterial diseases that cause global production constraints have become major challenges to agriculture worldwide. To promote the discovery development new bactericides, imidazole-labeled 1,3,4-oxadiazole thioethers were first fabricated by integrating crucially bioactive scaffolds imidazole motif skeleton in a single molecular architecture. Subsequently, superior antibacterial compound A6 was gradually discovered possessing excellent competence against pathogens Xanthomonas oryzae pv axonopodis citri with EC50 values 0.734 1.79 μg/mL, respectively. These better than those commercial agents bismerthiazol (92.6 μg/mL) thiodiazole copper (77.0 μg/mL). Further modifying moiety into imidazolium scaffold led an array potent compounds providing corresponding minimum 0.295 0.607 μg/mL two strains. Moreover, plausible action mechanism for attacking proposed based on concentration dependence scanning electron microscopy, transmission fluorescence microscopy images. Given simple structures, easy synthetic procedure, highly efficient bioactivity, (or imidazolium)-labeled can be further explored developed as promising indicators drugs.