Ginson George, Farhan Mahmood Shah, Abbas Ali, Dileep Kumar Guddeti, Noura Alowaifi, Joseph Lee, Jian Chen, Ikhlas A Khan, Xing-Cong Li
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引用次数: 0
Abstract
Imported fire ants are significant agricultural pests. Repellents can be used to prevent foraging fire ants from entering sensitive areas, including electrical equipment, nursing homes, and hospitals. Bioassay-guided fractionation of the essential oil extracted from gurjun balsam (Dipterocarpus turbinatus) resulted in the identification of (-)-α-copaene (1) as the repellent constituent with a minimum repellent effective dose (MRED) of 15.6 μg/g against both red imported fire ants (Solenopsis invicta) and hybrid imported fire ants (Solenopsis invicta × Solenopsis richteri). Stereoselective oxidation of 1 via autoxidation and chemical methods produced (-)-5R-hydroperoxy-α-copaene (2), (+)-3S-hydroperoxycopa-4-ene (3), (-)-α-copaene oxide (4), (+)-β-copaen-4α-ol (5), copaenediol (6), and copaene ketol (7). Reduction of 2 and 3 with triphenylphosphine afforded (-)-5R-hydroxy-α-copaene (2a) and (+)-3S-hydroxycopa-4-ene (3a), respectively, which led to the structural revision of copa-3-en-2α-ol and copa-2-en-4-ol as 2a and 3, respectively. The configurational assignment of compound 4 in the literature was also clarified by the detailed analysis of 2D NMR spectroscopic data. Compounds 2-7 showed repellency with MREDs ranging from 3.9 to 15.6 μg/g against hybrid and red imported fire ants, indicating that chemical modification can enhance the repellent effect of (-)-α-copaene.
期刊介绍：
The Journal of Natural Products invites and publishes papers that make substantial and scholarly contributions to the area of natural products research. Contributions may relate to the chemistry and/or biochemistry of naturally occurring compounds or the biology of living systems from which they are obtained.
Specifically, there may be articles that describe secondary metabolites of microorganisms, including antibiotics and mycotoxins; physiologically active compounds from terrestrial and marine plants and animals; biochemical studies, including biosynthesis and microbiological transformations; fermentation and plant tissue culture; the isolation, structure elucidation, and chemical synthesis of novel compounds from nature; and the pharmacology of compounds of natural origin.
When new compounds are reported, manuscripts describing their biological activity are much preferred.
Specifically, there may be articles that describe secondary metabolites of microorganisms, including antibiotics and mycotoxins; physiologically active compounds from terrestrial and marine plants and animals; biochemical studies, including biosynthesis and microbiological transformations; fermentation and plant tissue culture; the isolation, structure elucidation, and chemical synthesis of novel compounds from nature; and the pharmacology of compounds of natural origin.
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