Isocoma wrightii

A new sesquiterpene called isocomene (593) has been isolated from the dried stems and leaves of the goldenrod Isocoma Wrightii. Its structure was established by conversion to diol 594 and analysis of the latter by X-ray methods.440 ... 

C15H24, Mr 204.36, cryst., mp. 60-63 °C, bp. 65-70°C (46.6 Pa), [a]g -85° (CHCl,). A natural tri-quinane from Isocoma wrightii, Asteraceae of South west USA that is toxic for cattle and sheep, and the roots of South African Berkheya species and Senecio isa-tideus. On account of its unusual structure composed... 

C,sH24, Mr 204.36, oil, bp. 65-70°C (33.3 Pa), [aJo -15.8° (CHCI3). A natural triquinane hydrocarbon with a [3.3.3]propellane structure from Isocoma wrightii (Asteraceae), an indigenous species of south west USA toxic to cattle and sheep, from South African Berkheya species, and the roots of Senecio isatideusK Derivatives of M. show antiproliferative activity. ... 

Compounds with similar structure have been implicated in cases of livestock and human poisoning by Eupatorium rugosum, white snakeroot, in the eastern United States (Beier and Norman, 1990 Beier et al., 1987). This plantpoisoning syndrome was once a major problem and was considered an illness, often called milk sickness (Beier and Norman, 1990 Kingsbury, 1964). The lipophilic compounds of white snakeroot are excreted by lactating animals, usually cattle. In the southwestern United States, where white snakeroot does not grow, another species. Isocoma wrightii (syn. Haplopappus heterophyllus), has... 

Zalkow L H, Harris R N, Van Derveer D, Bertrand J A 1977 Isocomene a novel sesquiterpene from Isocoma wrightii. X-ray crystal structure of the corresponding diol. J Chem Soc Chem Commun 456-457... 

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