GC-FID-MS and X-ray Diffraction for the Detailed Evaluation of the Volatiles From Senecio filaginoides

The medicinal aromatic plant Senecio filaginoides DC, which is very widespread in the Patagonia region, was harvested at the vegetative, flowering, and fructification stages. The materials were extracted by hydrodistillation, yielding in average 0.34% v/w of essential oils with a pleasant sweet and greenish scent. A total of 56 components were identified by gas chromatography using flame ionization detection and mass spectra measurements, representing 96.1%-97.6% of the total oil. The sesquiterpenoid 10αH-furanoeremophil-1-one (1) appeared as a major constituent (16.2%-26.9%) of the oil. It could be isolated by cooling the oil at 4°C, thus yielding yellow crystalline solids. Its stereochemistry was assigned by single-crystal X-ray diffraction since previous studies identified the compound with different stereochemistries. The use of classical separation and analytical methodologies remains as a very useful strategy for the correct identification of compounds present in the volatile fraction of a plant and is a route for potential industrial applications.