Aedes aegypti mosquitoes are responsible for transmission of many viral diseases, such as Zika fever, dengue fever, yellow fever, and chikungunya. Emergence of resistance to currently used pesticides among mosquitoes ...Aedes aegypti mosquitoes are responsible for transmission of many viral diseases, such as Zika fever, dengue fever, yellow fever, and chikungunya. Emergence of resistance to currently used pesticides among mosquitoes has increased the importance for the search for novel mosquito control agents. Natural products, particularly plant and microbe derived secondary metabolites, are good sources in the search for such compounds. Ammi visnaga (Lam.) Lamarck is a plant in the Apiaceae family native to North Africa, Europe, and Asia. In the search for environmentally benign and effective insecticides as part of an ongoing joint effort between the USDA (US Department of Agriculture) and the DWFP (Deployed War Fighter Protection) program sponsored by the Department of Defense, we have investigated ethyl acetate extract of A. visnaga seeds. Two furanochromones, khellin and visnagin that exhibited larvicide activity against Aedes aegypti mosquito larvae were isolated from the ethyl acetate extract of the seeds by bioassay-guided fractionation. This is the first report of mosquito larvicidal activity of khellin and visnagin.展开更多
The structure of osthole has been modified to improve its larvicidal activity against mosquitoes. A new efficient synthesis of osthole derivatives with Grignard reagents has been developed, which employs CuI and LiCI ...The structure of osthole has been modified to improve its larvicidal activity against mosquitoes. A new efficient synthesis of osthole derivatives with Grignard reagents has been developed, which employs CuI and LiCI as pro- moters and covers a broad range of substrates to afford the corresponding products in mild to good yields （up to 83%）. Bio-activity evaluation showed that several products exhibited better activities than osthole.展开更多
文摘Aedes aegypti mosquitoes are responsible for transmission of many viral diseases, such as Zika fever, dengue fever, yellow fever, and chikungunya. Emergence of resistance to currently used pesticides among mosquitoes has increased the importance for the search for novel mosquito control agents. Natural products, particularly plant and microbe derived secondary metabolites, are good sources in the search for such compounds. Ammi visnaga (Lam.) Lamarck is a plant in the Apiaceae family native to North Africa, Europe, and Asia. In the search for environmentally benign and effective insecticides as part of an ongoing joint effort between the USDA (US Department of Agriculture) and the DWFP (Deployed War Fighter Protection) program sponsored by the Department of Defense, we have investigated ethyl acetate extract of A. visnaga seeds. Two furanochromones, khellin and visnagin that exhibited larvicide activity against Aedes aegypti mosquito larvae were isolated from the ethyl acetate extract of the seeds by bioassay-guided fractionation. This is the first report of mosquito larvicidal activity of khellin and visnagin.
基金This work was financially supported by the National Natural Science Foundation of China （Nos. 21272129 and 21372133） and ＂111＂ Project of Ministry of Educa- tion of China （No. B06005）. We also thank Prof. Er-Cai Shang and Dr. Yan-Jun Guo for their kind advices.
文摘The structure of osthole has been modified to improve its larvicidal activity against mosquitoes. A new efficient synthesis of osthole derivatives with Grignard reagents has been developed, which employs CuI and LiCI as pro- moters and covers a broad range of substrates to afford the corresponding products in mild to good yields （up to 83%）. Bio-activity evaluation showed that several products exhibited better activities than osthole.
