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Biosynthesis of the Pyrethrins
Nature, 1961RECENT work1 has indicated that mevalonic acid (I) is an intermediate in the biosynthesis of terpenoid compounds. We now wish to report some experiments which indicate that this acid is also involved in the biosynthesis of the ‘pyrethrins’, the insecticidal constituents of the pyrethrum plant, Chrysanthemum cinerariaefolium.
Helene S. Inglis +3 more
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Pyrethrins and Pyrethroids in Dermatology
Archives of Dermatology, 1990In 1987, we reviewed the history and development of natural pyrethrins and man-made synthetic pyrethroids.1The following is a condensation of that report, an update on developments to 1989, and comments on a more recent study of permethrin 5% cream for the treatment of scabies that appears in this issue of theArchives.2 PYRETHRUM AND PYRETHRINS The ...
David Taplin, Terri L. Meinking
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Oxidative Metabolism of Pyrethrins in Mammals
Nature, 1971THE natural pyrethrins present in pyrethrum flowers (Chrysanthemum cinerariaefolium) have attracted attention for more than a century because they are powerful insecticides yet have very low toxicity to mammals1,2. Concern about the persistence of some insecticides in mammals and in the environment has stimulated a consideration of the degradability of
Ella C. Kimmel +3 more
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Chemistry of the Natural Pyrethrins
1961The flowers of the herbaceous perennial Chrysanthemum cinerariaefolium Vis. (synonym, Pyrethrum cinerariaefolium Trev.), a member of the Compositae family, are valued for their insecticidal properties: the history of their employment has been discussed by Gnadinger (77,78).
Michael Elliott, L. Crombie
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Toxicological Reviews, 2005
The pyrethrins have a long and fascinating history. They were derived from dried chrysanthemum flower heads that were found to have pesticidal activity centuries ago. They comprise a complex mixture of six main chemicals. Commercial formulations usually contain piperonyl butoxide, which inhibits metabolic degradation of the active ingredients ...
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The pyrethrins have a long and fascinating history. They were derived from dried chrysanthemum flower heads that were found to have pesticidal activity centuries ago. They comprise a complex mixture of six main chemicals. Commercial formulations usually contain piperonyl butoxide, which inhibits metabolic degradation of the active ingredients ...
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Total Synthesis of some Pyrethrins
Nature, 1948IN view of recent publications in the United States, it is desirable to record briefly some of the results obtained by us during the past year or so. Following the demonstration by LaForge and Barthel1 of the heterogeneity of ‘pyrethrolone', the alcoholic component of the pyrethrins, and the revision by LaForge and Soloway2 of e structures of the ...
Michael Elliott +3 more
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An examination of polymerized pyrethrins
Journal of the Science of Food and Agriculture, 1950AbstractThe resinous material formed by polymerization of a highly purified pyrethrum concentrate has been examined. It was insoluble in cold light petroleum or deodorized kerosene, and gave high values for apparent pyrethrins by the Seil or mercury‐reduction methods, although it was devoid of insecticidal effect on houseflies.
Wm. Mitchell, A. Campbell
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Antiplasmodial and Antitrypanosomal Activity of Pyrethrins and Pyrethroids
Journal of Agricultural and Food Chemistry, 2011In a screen of 1800 plant and fungal extracts for antiplasmodial, antitrypanosomal, and leishmanicidal activity, the n-hexane extract of Chrysanthemum cinerariifolium (Trevir.) Vis. flowers showed strong activity against Plasmodium falciparum. We isolated the five pyrethrins [i.e., pyrethrin II (1), jasmolin II (2), cinerin II (3), pyrethrin I (4), and
Yoshie Hata +8 more
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Paper Chromatography of Pyrethrins and their Derivatives [PDF]
Nature, 1956 VARIOUS methods have been described for the chromatographic separation of pyrethrin-type compounds. Alumina, silica and kieselguhr have been used as adsorbents for separation of ‘pyrethrin I’ from ‘pyrethrin II’1–3. A separation of cinerin I from ‘pyrethrin I’, and ‘cinerin II’ from ‘pyrethrin II’, has almost certainly been achieved by Ward2, using ...
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Pyrethrin and Pyrethroid Insecticides
Veterinary Clinics of North America: Small Animal Practice, 1990Pyrethroids have a wide spectrum of insecticidal potency, vertebrate toxicity, and environmental stability. The exceptionally high selectivity ratios of pyrethrins and pyrethroids have resulted in their use for insect control in numerous formulations.
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