title: Synthesis and antifungal activity of 2-allylphenol derivatives against fungal plant pathogens.
abstract: 2-Allylphenol (2-AP) is an effective fungicide against a number of plant pathogens, which can be metabolized and bio-transformed to four chemical compounds by Rhizoctonia cerealis. To determine if its degradation affects antifungal activity, two major metabolites derived from 2-AP including 2-(2-hydroxypropyl) phenol and 2-(3-hydroxypropyl) phenol were synthesized. Inhibition of mycelial growth of several plant pathogens by the metabolites was evaluated, and structures of two metabolites were determined by hydrogen nuclear magnetic resonance (1H NMR). Among these metabolites, only 2-(2-hydroxypropyl) phenol inhibited test pathogens effectively. EC50values of 2-(2-hydroxypropyl) phenol for inhibition of mycelial growth of R. cerealis, Pythium aphanidermatum, Valsa mali and Botrytis cinerea ranged from 1.0 to 23.5μg/ml, which were lower than the parental fungicide 2-AP that ranged from 8.2 to 48.8μg/ml. Hyphae of R. cerealis and P. aphanidermatum treated with 2-(2-hydroxypropyl) phenol were twisted. Newly developed hyphae were slender, twisted and swollen on the tip, while old hyphae were hollow and ruptured. This is the first report indicating the formation of 2-(2-hydroxypropyl) phenol may have contributed to toxicity of 2-allylphenol in control of plant pathogens.
authors.affiliation: Chemistry and Pharmacy College, Qingdao Agricultural University, Shandong 266109, China; Department of Plant Pathology, Coastal Plain Experiment Station, University of Georgia, Tifton, GA 31794, USA.
authors.forename: Tianli
authors.initials: T
authors.lastname: Qu
authors.affiliation: Key Laboratory of Plant Pathology, Department of Plant Pathology, China Agricultural University, Beijing 100193, China; Beijing Engineering Research Center of Seed and Plant Health, Beijing Key Laboratory of Seed Disease Testing and Control, Beijing 100193, China.
authors.forename: Shumei
authors.initials: S
authors.lastname: Gao
authors.affiliation: Key Laboratory of Plant Pathology, Department of Plant Pathology, China Agricultural University, Beijing 100193, China; Beijing Engineering Research Center of Seed and Plant Health, Beijing Key Laboratory of Seed Disease Testing and Control, Beijing 100193, China. Electronic address: lijq231@cau.edu.cn.
authors.forename: Jianqiang
authors.initials: J
authors.lastname: Li
authors.affiliation: School of Food and Agriculture, University of Maine, Orono, ME 04469, USA.
authors.forename: Jianjun J
authors.initials: JJ
authors.lastname: Hao
authors.affiliation: Department of Plant Pathology, Coastal Plain Experiment Station, University of Georgia, Tifton, GA 31794, USA.
authors.forename: Pingsheng
authors.initials: P
authors.lastname: Ji
mesh_terms: D001203:Ascomycota / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development; D020171:Botrytis / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development; D005659:Fungicides, Industrial / Q000633:toxicity*; D025301:Hyphae / Q000166:cytology / Q000187:drug effects; D025282:Mycelium / Q000187:drug effects / Q000254:growth & development; D010636:Phenols / Q000633:toxicity*; D010935:Plant Diseases / Q000517:prevention & control; D011775:Pythium / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development; D012232:Rhizoctonia / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development
chemical_list: D005659:Fungicides, Industrial; D010636:Phenols; C099328:2-allylphenol
keywords: 2-(2-Hydroxypropyl) phenol; 2-(3-Hydroxypropyl) phenol; 2-Allylphenol; Fungal plant pathogen