Ecdysteroids as Insect Control Agents: A New Ecdysteroid from Stem Bark of Vitex canescens
نویسندگان
چکیده
North Bangkok. ** Department of Chemistry, Faculty of Science, Ramkhamhaeng University. Abstract A new ecdysteroid, P5, has been isolated from the stem bark of aged trees (with flower) of vitex canescens. 20-Hydroxyecdysone, makisterone A, 24-epi-makisterone A, and canescensterone have also been isolated from both young trees (without flower) and aged trees (with flower) of vitex canescens. The methods of extraction of the ecdysteroids from vitex canescens are given and the melting points, infrared absorption spectra, nuclear magnetic resonance spectra and mass spectra of the ecdysteroids are reported.
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