Fraxinellone, a naturally occurring degraded limonoid, is mainly isolated from Dictamnus dasycarpus and Melia azedarach. In continuation of our program aimed at the discovery of plant natural products-based insecticid...Fraxinellone, a naturally occurring degraded limonoid, is mainly isolated from Dictamnus dasycarpus and Melia azedarach. In continuation of our program aimed at the discovery of plant natural products-based insecticidal agents, twenty-two new ethers from furyl-ring-based acylation derivatives were prepared by structural modifications of fraxinellone. Their insecticidal activity was evaluated against the pre-thirdinstar larvae of Mythimna separata Walker in vivo. Among them, compounds 5 e and 5 j exhibited more potent insecticidal activity than toosendanin with the final mortality rates greater than 60%. Their structure-activity relationships were also discussed.展开更多
Fraxinellone significantly reduced the relative growth rate, food consumption rate as well as the efficiency of conversion of ingested food into biomass of Heliothis virescens when incorporated into artificial diets a...Fraxinellone significantly reduced the relative growth rate, food consumption rate as well as the efficiency of conversion of ingested food into biomass of Heliothis virescens when incorporated into artificial diets at concentrations of 4.31 x 10.5 mol/L and above. After being fed with fraxinellone-treated diets for 24 h, the larval midguts of H. vb＇escens possess significantly lower activities of α-amylase and non-specific proteases and higher activities of cytochrome P450s. In vitro, the compound did not inhibit the activities of u-amylase and non-specific proteases extracted from the larval midguts. Clear evidence of post-ingestive toxicity of fraxinellone to midgut cells was observed under an electron microscope. The modes of action of the compound against insects were discussed.展开更多
Aim To gain the active compounds fromDictamnus dasycarpus.Method The solvent partition,preparative TLC,spectral analysis and bioassay are used to gain the active compounds.Results Fraxinellone is a main biological act...Aim To gain the active compounds fromDictamnus dasycarpus.Method The solvent partition,preparative TLC,spectral analysis and bioassay are used to gain the active compounds.Results Fraxinellone is a main biological actives substance fromD.dasycarpus was gained.Conclusion Its antifeeding rate and death rate of 72hat 0.21%(mass percent) against Mythimna setarata were 90.4%and 95.2%,respectively.展开更多
基金supported by the National Natural Science Foundation of China (No. 31672071)Special Funds of Central Colleges Basic Scientific Research Operating Expenses (No. 2452015096)
文摘Fraxinellone, a naturally occurring degraded limonoid, is mainly isolated from Dictamnus dasycarpus and Melia azedarach. In continuation of our program aimed at the discovery of plant natural products-based insecticidal agents, twenty-two new ethers from furyl-ring-based acylation derivatives were prepared by structural modifications of fraxinellone. Their insecticidal activity was evaluated against the pre-thirdinstar larvae of Mythimna separata Walker in vivo. Among them, compounds 5 e and 5 j exhibited more potent insecticidal activity than toosendanin with the final mortality rates greater than 60%. Their structure-activity relationships were also discussed.
文摘Fraxinellone significantly reduced the relative growth rate, food consumption rate as well as the efficiency of conversion of ingested food into biomass of Heliothis virescens when incorporated into artificial diets at concentrations of 4.31 x 10.5 mol/L and above. After being fed with fraxinellone-treated diets for 24 h, the larval midguts of H. vb＇escens possess significantly lower activities of α-amylase and non-specific proteases and higher activities of cytochrome P450s. In vitro, the compound did not inhibit the activities of u-amylase and non-specific proteases extracted from the larval midguts. Clear evidence of post-ingestive toxicity of fraxinellone to midgut cells was observed under an electron microscope. The modes of action of the compound against insects were discussed.
文摘Aim To gain the active compounds fromDictamnus dasycarpus.Method The solvent partition,preparative TLC,spectral analysis and bioassay are used to gain the active compounds.Results Fraxinellone is a main biological actives substance fromD.dasycarpus was gained.Conclusion Its antifeeding rate and death rate of 72hat 0.21%(mass percent) against Mythimna setarata were 90.4%and 95.2%,respectively.
