title: Synthesis and antifungal activities of carabrol ester derivatives.
abstract: Thirty-eight new ester derivatives of carabrol were designed, synthesized, and characterized by (1)H and (13)C NMR and HR-ESI-MS. Their antifungal activities against the fungal pathogen  Colletotrichum lagenarium  were evaluated using a spore germination assay. Of these 38 ester derivatives, 16 showed higher antifungal activity than that of carabrol and 7 showed higher antifungal activity than that of carabrone. It was found that the C-4 position of carabrol was a key position involving its antifungal activity, which showed the variation of 50% inhibition concentration (IC(50)) from 2.70 to 52.33 μg/mL. When substituted by the phenyl ring, the ester derivatives with electron-attracting groups showed higher activity than those with electron-donating ones. Two ester derivatives, carabryl 4-cynaobenzoate (II-17, IC(50) 2.70 μg/mL) and carabryl 4-isopropylbenzoate (II-27, IC(50) 2.82 μg/mL), showed only slightly lower antifungal activity than that of the positive control chlorothalonil (IC(50) 0.87 μg/mL) and have been identified as promising leads for development of new environmentally friendly fungicides.
authors.affiliation: Research & Development Center of Biorational Pesticide, Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Northwest A&F University, Yangling, China.
authors.forename: Jun-Tao
authors.initials: JT
authors.lastname: Feng
authors.forename: Hao
authors.initials: H
authors.lastname: Wang
authors.forename: Shuang-Xi
authors.initials: SX
authors.lastname: Ren
authors.forename: Jun
authors.initials: J
authors.lastname: He
authors.forename: Yong
authors.initials: Y
authors.lastname: Liu
authors.forename: Xing
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000935:Antifungal Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D019659:Asteraceae / Q000737:chemistry*; D020231:Colletotrichum / Q000187:drug effects / Q000254:growth & development; D004952:Esters / Q000737:chemistry / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D010936:Plant Extracts / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D012717:Sesquiterpenes / Q000737:chemistry* / Q000494:pharmacology; D013172:Spores, Fungal / Q000187:drug effects / Q000254:growth & development; D013329:Structure-Activity Relationship
chemical_list: D000935:Antifungal Agents; D004952:Esters; D010936:Plant Extracts; D012717:Sesquiterpenes; C547206:carabrol