title: Structure elucidation of a pungent compound in black cardamom: Amomum tsao-ko Crevost et Lemarié (Zingiberaceae).
abstract: Natural plant extracts containing taste modifier compounds will gain more commercial interest in the future. Black cardamom, Amomum tsao-ko Crevost et Lemarié, used as a spice in Asia, produces a nice refreshing effect in the mouth. Therefore, an ethyl acetate extract was prepared, and constituents were separated by liquid chromatography. Guided by the tasting of each fraction (LC tasting), a new pungent compound was discovered, (+/-)-trans-2,3,3a,7a-tetrahydro-1H-indene-4-carbaldehyde. To confirm this new structure, a synthesis was performed starting from cyclopentene-1-carbaldehyde. The Wittig conditions were determined to control the stereochemistry of the ring fusion to prepare (+/-)-trans-(2,3,3a,7a-tetrahydro-1 H-inden-4-yl) methanol and (+/-)-cis-(2,3,3a,7a-tetrahydro-1H-inden-4-yl) methanol. After oxidation, (+/-)-trans-2,3,3a,7a-tetrahydro-1H-indene-4-carbaldehyde and (+/-)-cis-2,3,3a,7a-tetrahydro-1H-indene-4-carbaldehyde were tasted in water and only the trans-2,3,3a,7a-tetrahydro-1H-indene-4-carbaldehyde, present in black cardamom, produced a trigeminal effect in the mouth.
authors.affiliation: Firmenich SA, Corporate R&D Division, Geneva, Switzerland. christian.starkenmann@firmenich.com
authors.forename: Christian
authors.initials: C
authors.lastname: Starkenmann
authors.forename: Fabienne
authors.initials: F
authors.lastname: Mayenzet
authors.forename: Robert
authors.initials: R
authors.lastname: Brauchli
authors.forename: Laurent
authors.initials: L
authors.lastname: Wunsche
authors.forename: Christian
authors.initials: C
authors.lastname: Vial
mesh_terms: D028523:Elettaria / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007192:Indenes / Q000032:analysis / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D009812:Odorants / Q000032:analysis*; D012639:Seeds / Q000737:chemistry*; D013649:Taste
chemical_list: D007192:Indenes; C526858:trans-2,3,3a,7a-tetrahydro-1H-indene-4-carbaldehyde