Phytochemistry 65: 3057–3063, (2004).
The polar bioactive fractions of Helianthus annuus cv. Stella and SH-222 have yielded eight apocarotenoids, two of them isolated for the first time as natural products (annuionones F and G). The isolation of higher amounts of annuionones A and E allowed us to realize a more comprehensive spectroscopical study. We propose a revised structure for annuionone A, B and E based on careful re-analyses of new spectroscopical data.