Structure elucidation of a pungent compound in black cardamom: Amomum tsao-ko Crevost et Lemarié (Zingiberaceae).
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.
Starkenmann
Christian
C
Firmenich SA, Corporate R&D Division, Geneva, Switzerland. christian.starkenmann@firmenich.com
Mayenzet
Fabienne
F
Brauchli
Robert
R
Wunsche
Laurent
L
Vial
Christian
C
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
D007192:Indenes; C526858:trans-2,3,3a,7a-tetrahydro-1H-indene-4-carbaldehyde