(R)-(+)-(E)-alpha-ionone - violet-like, fruiy, raspberry-like, flowery, strong impact Odor Threshold = 0.03 - 328 ppb = (R)-(+)-(E)- 4-(2,6,6-Trimethyl-cyclohex-2-enyl)-but-3-en-2-one Note: olfactory threshold ratio for alpha-ionone enantiomers varied among subjects by 3-4 orders of magnitude. Ref: E.H. Polak, A. M. Fombon, C. Tilquin and P. H. Punter, Sensory evidence for olfactory receptors with opposite chiral selectivity, Bahav. Brain Res., 31, 199-206 (1989); L.J. van Gemert, Compilations of odour threshold values in ar and water, Boelens Aroma Chemical Information Service, Publisher (1999), p. B-118; Mans H. Boelens, Harrie Boelens & Leo J. van Gemert, Perfumer & Flavorist, Vol. 18, No. 6, 1-15, 1993   Note - Haarmann & Reimer researchers reported in 1991 (P. Werkhoff, W. Bretschneider, M. Guentert, R. Hopp, H. Surburg in Flavor Science and Technology [Eds.: Y. Bessiere, A. F. Thomas], J. Wiley & Sons, New York, 1990, pp. 33-36) a violet-like, fruity, raspberry-type, floral odor with a threshold of 0.525 ppb for (R)-(+)-alpha-ionone, and a woody, cedarwood-type odor with a threshold of 20-40 ppb for its enantiomer. These olfactory differences were confirmed by Firmenich perfumers in 1992, [C. Fehr, O. Guntern, Helv. Chim. Acta 1992, 75, 1023-1028 ] but a recent study by Elisabetta Brenna, Claudio Fuganti, Stefano Serra,and Philip Kraft (Eur. J. Org. Chem. 2002, 967-978) was not able to confirm such strong deviations in the odor profiles or thresholds of the alpha-ionone enantiomers.

(S)-(-)-(E)-alpha-ionone - woody, cedar wood like, raspberry & beta-ionone like Odor Threshold = 0.1 - 656 ppb = (S)-(-)-(E)- 4-(2,6,6-Trimethyl-cyclohex-2-enyl)-but-3-en-2-one Note: olfactory threshold ratio for alpha-ionone enantiomers varied among subjects by 3-4 orders of magnitude. Ref: E.H. Polak, et. al., Bahav. Brain Res., 31, 199-206 (1989); L.J. van Gemert, Compilations of odour threshold values in ar and water, Boelens Aroma Chemical Information Service, Publisher (1999), p. B-118; Mans H. Boelens, Harrie Boelens & Leo J. van Gemert, Perfumer & Flavorist, Vol. 18, No. 6, 1-15, 1993

Note - Haarmann & Reimer researchers reported in 1991 (P. Werkhoff, W. Bretschneider, M. Guentert, R. Hopp, H. Surburg in Flavor Science and Technology [Eds.: Y. Bessiere, A. F. Thomas], J. Wiley & Sons, New York, 1990, pp. 33-36) a violet-like, fruity, raspberry-type, floral odor with a threshold of 0.525 ppb for (R)-(+)-alpha-ionone, and a woody, cedarwood-type odor with a threshold of 20-40 ppb for its enantiomer. These olfactory differences were confirmed by Firmenich perfumers in 1992 [C. Fehr, O. Guntern, Helv. Chim. Acta 1992, 75, 1023-1028 ], but a recent study by Elisabetta Brenna, Claudio Fuganti, Stefano Serra,and Philip Kraft (Eur. J. Org. Chem. 2002, 967-978) was not able to confirm such strong deviations in the odor profiles or thresholds of the alpha-ionone enantiomers.

 

 

 

Ionones, Irones, Damascones & Structurally Related Odorants

Acyclics (Alcohols, Esters, Acids, Aldehydes)

Lactones

Sesquiterpenoid Related Odorants