Constituents of the essential oil from the rhizomes of Hedychium acumnatum Roscoe

Seventy‐five constituents (99%) of the essential oil of the rhizomes of Hedychium acuminatum Roscoe (Zingiber‐aceae) were identified. The main constituent is 1,8‐cineole (76%). The oil contains 0.5% of 2‐alkanones, 0.6% of sesquiterpene hydrocarbons, 1.3% of sesquiterpene alcohols and 0.6% of drimane and labdane derivatives. Olfactorily interesting are the drim‐8(12)‐en‐11‐al (syn. albicanal or γ‐bicyclofarnesal) and the 11‐nordrim‐8‐en‐12‐al, as well as the known trans‐5,5,8a‐trimethyldecal‐2‐one and γ‐bicyclohomofarnesal (Ambralγ). The structures of the new sesquiterpene hdrocarbon, drim‐8(12)‐ene and of the new 15,16‐bisnorlabda‐8(17),12‐dien‐14‐al were confumed by 1H‐ and 13C‐NMR data.