Feverfew (Tanacetum parthenium) as a prophylactic treatment for migraine: a double-blind placebo-controlled study

Nature’s Migraine Treatment: Isolation and Structure Elucidation of Parthenolide from Tanacetum parthenium

“…Further analysis of the 13 C and DEPT spectra supplies evidence of two CH 3 , five CH 2 , and four CH signals in addition to four quaternary carbon atoms. It may be deduced that, of the 15 signals present in the 13 C NMR spectrum, one represents the carbonyl carbon of a conjugated ester, four are indicative of olefinic carbons, and three peaks signify carbons with a carbonÀoxygen single bond. Knowing the molecular weight of the compound to be 248.1646 and having proven the existence of 15 carbons and 20 hydrogens, three oxygen atoms must be present, therefore, deriving an empirical formula of C 15 H 20 O 3 .…”

“…Consideration of these features, coupled with application of the unsaturation equivalent rule, leads to an assumption that a lactone ring is present. Resonances for two carbon atoms in the chemical shift region of the 13 C NMR spectrum consistent with a CÀO single bond, together with one unassigned oxygen atom, suggests ether or possibly epoxide functionality. IR spectral evidence of a ring deformation band at 984 cm À1 is consistent with the presence of an epoxide.…”

“…A peak representing an ion with an m/z value of 248.1646 justifies this. Referring to the 13 C NMR spectrum, 15 carbon signals are evident, perhaps representative of a sesquiterpene-like compound, whereas a total proton count of 20 is provided by the 1 H NMR spectrum. Further analysis of the 13 C and DEPT spectra supplies evidence of two CH 3 , five CH 2 , and four CH signals in addition to four quaternary carbon atoms.…”

“…Referring to the 13 C NMR spectrum, 15 carbon signals are evident, perhaps representative of a sesquiterpene-like compound, whereas a total proton count of 20 is provided by the 1 H NMR spectrum. Further analysis of the 13 C and DEPT spectra supplies evidence of two CH 3 , five CH 2 , and four CH signals in addition to four quaternary carbon atoms. It may be deduced that, of the 15 signals present in the 13 C NMR spectrum, one represents the carbonyl carbon of a conjugated ester, four are indicative of olefinic carbons, and three peaks signify carbons with a carbonÀoxygen single bond.…”

“…Imperative to complete elucidation of the structure is detailed use of 1-D and 2-D NMR spectroscopic data. Using HHÀCOSY, HMQC, and HMBC spectra, in conjunction with 1 H NMR and 13 C NMR spectra, the CÀH framework of the molecule is assigned. One approach to the elucidation of the structure, shown in Figure 2, is outlined in the Supporting Information.…”