title: Synthesis and biological evaluation of novel fluorine-containing stilbene derivatives as fungicidal agents against phytopathogenic fungi.
abstract: The rising development of resistance to conventional fungicides is driving the search for new alternative candidates to control plant diseases. In this study, a series of new fluorine-containing stilbene derivatives was synthesized on the basis of our previous quantitative structure-activity relationship analysis results. Bioassays in vivo revealed that the title compounds exhibited potent fungicidal activities against phytopathogenic fungi (Colletotrichum lagenarium and Pseudoperonospora cubensis) from cucumber plants. In comparison to the previous results, the introduction of a fluorine moiety showed improved activities of some compounds against those fungi. Notably, compound 9 exhibited a control efficacy against C. lagenarium (83.4 ± 1.3%) comparable to that of commercial fungicide (82.7 ± 1.7%). For further understanding the possible mode of action of the stilbene against C. lagenarium, the effects on hyphal morphology, electrolyte leakage, and respiration of mycelial cell suspension were studied. Microscopic observation showed considerably deformed mycelial morphology. The conductivity of mycelial suspension increased in the presence of compound 9, whereas no significantly inhibitory effect on respiration was observed. Taken together, the fungicidal mechanism of this stilbene is associated with its membrane disruption effect, resulting in increased membrane permeability. These results provide important clues for mechanistic study and derivatization of stilbenes as alternative sources of fungicidal agents for plant disease control.
authors.affiliation: School of Chemistry and Chemical Engineering, South China University of Technology , Guangzhou, Guangdong 510640, People's Republic of China.
authors.forename: Weilin
authors.initials: W
authors.lastname: Jian
authors.affiliation: School of Chemistry and Chemical Engineering, South China University of Technology , Guangzhou, Guangdong 510640, People's Republic of China.
authors.forename: Daohang
authors.initials: D
authors.lastname: He
authors.affiliation: Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University , Guangzhou, Guangdong 510642, People's Republic of China.
authors.forename: Pinggen
authors.initials: P
authors.lastname: Xi
authors.affiliation: School of Chemistry and Chemical Engineering, South China University of Technology , Guangzhou, Guangdong 510640, People's Republic of China.
authors.forename: Xinwei
authors.initials: X
authors.lastname: Li
mesh_terms: D020231:Colletotrichum / Q000187:drug effects; D018553:Cucumis sativus / Q000382:microbiology; D005461:Fluorine / Q000737:chemistry / Q000494:pharmacology*; D005659:Fungicides, Industrial / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D009868:Oomycetes / Q000187:drug effects; D010935:Plant Diseases / Q000382:microbiology* / Q000517:prevention & control; D021281:Quantitative Structure-Activity Relationship; D013267:Stilbenes / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D005659:Fungicides, Industrial; D013267:Stilbenes; D005461:Fluorine
keywords: Colletotrichum lagenarium; electrolyte leakage; fluorine; fungicidal activity; mode of action; stilbene derivatives