Terpenes and Terpene Derivatives, XXXI. New Bisabolene Derivatives and a Salsolene Ketone from Artemisia sieberi Bess.

From the essential oil of Artemisia sieberi growing near Tehran some new bisabolene derivatives could be isolated. The structures of (−)‐dehydro‐1,8‐sesquicineole (1), (E)‐dehydro‐1,8‐sesquicineol‐12‐yl acetate (4), bisabola‐2,11‐dien‐10‐one inner 1,7‐acetal (14) and salsolene ketone 15 could be established by their 1H‐ and 13C‐NMR spectra. Sesquiphellandren‐7‐ol (11), a trace constituent of the oil, was identified by a comparison of its 1H‐NMR spectrum with that of sesquiphellandren‐9‐ol (bisacurol).