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Constituents of Calamintha ashei: effects on Florida sandhill species
Natural Product Communications (2010)
  • M. A Menelaou
  • H. P. Henandez
  • F. A. Macias
  • Jeffrey D Weidenhamer, Ashland University
  • G. B. Williamson
  • F. R. Fronczek
  • H. D. Fischer
  • N. H. Fischer
Chemical constituents of the perennial shrub Calamintha ashei have been characterized as part of our investigation of the allelopathic properties of this plant. Besides the known monoterpenes, (+)-evodone, (-)-calaminthone and (+)-desacetylcalaminthone, fresh aerial parts of C. ashei provided six new menthofurans, two new germacrane sesquiterpenes, and the six, known flavonoids: 5-desmethoxynobiletin, 5-hydroxy-6,7,8,4'-tetramethoxyflavone, 5,4'-dihydroxy-6,7,8,3'-tetramethoxyflavone, thymonin, 5,4'-dihydroxy-6,7-dimethoxyflavone and 6-hydroxy-7,3'-dimethoxyluteolin. The structures of the new compounds were elucidated by spectroscopic methods and comparison of their H-1 NMR spectra with those of structurally related compounds. The molecular structures of (+)-evodone, 5-desmethoxynobiletin (5-hydroxy-6,7,8,3',4'-pentamethoxyflavone) and the triacetate of thymonin (7,8,3'-trimethoxy-5,6,4'-triacetoxyflavone), were determined by single crystal X-ray diffraction. Saturated aqueous solutions of menthofuran, (+)-evodone, (-)-calaminthone, (+)-esacetylcalaminthone, 4 alpha,5 beta-diacetoxymenthofuran, as well as mixtures of (+)-evodone and (+)-desacetylcalaminthone inhibited the germination and root growth of Schizachyrium scoparium and Leptochloa dubia, two native Florida sandhill grasses, as well as Lactuca saliva. (+)-Evodone and (+)-desacetylcalaminthone were the most active. 5-Hydroxy-6,7,8,3',4'-pentamethoxyflavone and 5,4'-dihydroxy-6,7,8,3'-tetramethoxyflavone and mixtures of the two flavonoids in aqueous as well as in saturated aqueous solutions of ursolic acid were tested on the same species, but showed no significant activity.
  • sandhill grasses
Publication Date
Citation Information
M. A Menelaou, H. P. Henandez, F. A. Macias, Jeffrey D Weidenhamer, et al.. "Constituents of Calamintha ashei: effects on Florida sandhill species" Natural Product Communications Vol. 5 Iss. 5 (2010)
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