Structure Identification: |
American Journal of Essential Oil and Natural Products,2016,4(2):41-46. | Closely eluting bornyl and isobornyl acetates are chemotaxonomic markers in the Pinaceae by virtue of their unique mass spectra.[Reference: WebLink] | METHODS AND RESULTS:
Gas chromatography / mass spectrometry (GC/MS) of Abies balsamea, Picea mariana and Tsuga canadensis leaf essential oils assigned bornyl acetate as a major peak in A. balsamea and P. mariana, while Isobornyl acetate was identified as the major peak in T. canadensis. Though these two isomers elute closely on GC, their characteristic mass spectra allow unequivocal structural assignment. Under electron impact (EI) conditions, bornyl acetate, the endo-isomer, displays a significant molecular ion m/z 196, while Isobornyl acetate, the exo-form, displays a marked loss of acetic acid, resulting in a molecular ion an order of magnitude less intense than that of bornyl acetate.
CONCLUSIONS:
Thus GC/MS analyses with authentic standards may be prerequisite for chemotaxonomic studies on Pinaceae essential oils. A re-examination of reports of bornyl acetate in T. canadensis and of Isobornyl acetate in P. abies is suggested. |
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