title: Herbicidal activity of cineole derivatives.
abstract: Essential oils and their constituents have potential as ecologically acceptable pesticides that may also have novel modes of action. In this work hydroxy and ester derivatives of the naturally occurring monoterpenoids 1,8-cineole 3, the main component in most eucalyptus oils, and 1,4-cineole 4 were prepared and their pre-emergence herbicidal activity against annual ryegrass (Lolium rigidum) and radish (Raphanus sativus var. Long Scarlet) investigated in laboratory-based bioassays. 1,8-Cineole, eucalyptus oil and all derivatives showed a dose-dependent herbicidal activity against annual ryegrass and radish with many of the derivatives showing improved herbicidal activity relative to 1,8-cineole and high-cineole eucalyptus oil. Increased activity of cineole ester derivatives compared to their associated hydroxy-cineole and carboxylic acid was not observed. No relationship between lipophilicity of the carboxylic acid portion of cineole ester derivatives and herbicidal activity was observed. The results indicate that these cineole derivatives could be environmentally acceptable herbicides.
authors: School of Chemical and Mathematical Sciences, Murdoch University, Murdoch, Western Australia.
authors: Allan F M
authors: AF
authors: Barton
authors: Bernard
authors: B
authors: Dell
authors: Allan R
authors: AR
authors: Knight
mesh_terms: D003511:Cyclohexanols / Q000737:chemistry*; D000077591:Eucalyptol; D005052:Eucalyptus / Q000737:chemistry; D018525:Germination; D006540:Herbicides / Q000138:chemical synthesis* / Q000737:chemistry*; D008129:Lolium; D039821:Monoterpenes / Q000737:chemistry*; D009822:Oils, Volatile / Q000737:chemistry; D031224:Raphanus
chemical_list: D003511:Cyclohexanols; D006540:Herbicides; D039821:Monoterpenes; D009822:Oils, Volatile; D000077591:Eucalyptol