Abstract
The chemical composition of the commercial oil of tansy and of that obtained from a local tansy species was determined by means of gas–liquid chromatography. Both oils contained d-isothujone as the major component (68.5%, 58%). The commercial oil contained fairly large amounts of l-camphor (13.9%), whereas that from local plants had only traces of camphor and 19.8% of l-thujone. The minor components isolated and identified in both oils were l-α -pinene, l-camphene, d-sabinene, d-limonene, 1:8-cineole, γ-terpinene, p-cymene, d-terpinen-4-ol, l-carvotanacetone, and l-borneol. Small amounts of α-thujene, β-pinene, α-terpinene, terpinolene, neoisothujyl and isothujyl alcohols, and dihydrocarvone were identified by retention characteristics only. Car-4-ene, isomeric alloocimenes, and carvomenthone may also be present. An unknown, crystalline monoterpene alcohol with a terminal methylene group was isolated in small amounts. A sesquiterpene (3.7%) was obtained from the oil of local plants.Prefractionation of these oils by fractional distillation resulted in extensive isomerization of isothujone to dl-carvotanacetone. Such a rearrangement was not encountered during prefractionation by preparative gas–liquid chromatography.