ISSN:
1434-193X
Keywords:
New tricyclic sesquiterpene alcohols
;
Natural products
;
Essential oil
;
Compositae
;
Odoriferous substances
;
Chemistry
;
General Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The strong patchouli-like and woody smelling essential oil of the rhizomes of Echinops giganteus var. lelyi C. D. Adams (Compositae) contains only sesquiterpenes, which are mainly triquinanes. Besides the known tricyclic compounds, silphiperfol-5- (1, 3) and -6-ene (4), modhephen-2-ene (5), α- (6) and β-isocomene (7), silphiperfolan-7β-ol (12), presilphiperfolan-8-ol (13), silphiperfol-6-en-5-one (14) and 7-epi-silphiperfolan-6β-ol (20), the following compounds, three of which (15, 17, 18) have new skeletons, were found, for the first time, occurring naturally: presilphiperfol-7-ene (2), cameroonan-7-ol (15), an 11(7→8)-abeo-presilphiperfolan-7-ol, prenopsan-8-ol (17), a 1(8→7)-abeo-cameroonan-8-ol, and nopsan-4-ol (18), a 3(4→8)-abeo-prenopsan-4-ol, three diastereomers of silphiperfolan-6-ol (19, 21, 22), modheph-2-en-8-ol (23) and silphiperfola-4,7(14)-diene (24). All structures were elucidated by NMR spectroscopy. A biogenetic pathway from a presilphiperfolane cation C to the cameroonane K, prenopsane L and nopsane M cations is shown. Cameroonanol (15) and prenopsanol (17) are the main contributors to the fragrance of the total oil.
Type of Medium:
Electronic Resource
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