(S)-(-)-4-pentylbutan-4-olide - fatty, moldy, weak coconut note, less intense than (R)-isomer (Mosandl & Gunther, Evaluated as a 1% solution on blotter strips) Odor Threshold = 150 ppb in water (Yamamoto) Odor Threshold = 91 ppb in red wine (R.C. Brown) Also known as (S)-(-)-gamma-nonalactone Ref: Armin Mosandl & Claus Gunther, Stereoisomeric Flavor Compounds. 20. Structure and Properties of gamma-lactone Enantiomers, J. Agric. Food Chem., 1989, 37, 413-418; Mans H. Boelens, Harrie Boelens & Leo J. van Gemert, Perfumer & Flavorist, Vol. 18, No. 6, 1-15, 1993; Rachel Christine Brown, gamma-Lactones in wine: Synthesis, quantification and sensory studies, Ph.D. Thesis, Flinders University of South Australia, November 2007; Takeshi Yamamoto, Advances in the Transition Metal (Rh, RU)-Binap-Catalyzed Asymmetric Synthesis of Chral Compounds for Flavours and Fragrances and Their Associated Sensory Properties, in Current Topics in Flavours and Fragrances - Towards a New Millennium of Discovery, by K.A. Swift (Editor), Kluwer Academic Publishers, Dordrecht NL, 2000, pp. 33-58

(R)-(+)-4-pentylbutan-4-olide - strong, sweet, soft coconut with fatty-milky aspects (Mosandl & Gunther, Evaluated as a 1% solution on blotter strips) Odor Threshold = 220 ppb in water (Yamamoto) Odor Threshold = 285 ppb in red wine (R.C. Brown) Also known as (R)-(+)-gamma-nonalactone Ref: Armin Mosandl & Claus Gunther, Stereoisomeric Flavor Compounds. 20. Structure and Properties of gamma-lactone Enantiomers, J. Agric. Food Chem., 1989, 37, 413-418; Mans H. Boelens, Harrie Boelens & Leo J. van Gemert, Perfumer & Flavorist, Vol. 18, No. 6, 1-15, 1993; Rachel Christine Brown, gamma-Lactones in wine: Synthesis, quantification and sensory studies, Ph.D. Thesis, Flinders University of South Australia, November 2007; Takeshi Yamamoto, Advances in the Transition Metal (Rh, RU)-Binap-Catalyzed Asymmetric Synthesis of Chral Compounds for Flavours and Fragrances and Their Associated Sensory Properties, in Current Topics in Flavours and Fragrances - Towards a New Millennium of Discovery, by K.A. Swift (Editor), Kluwer Academic Publishers, Dordrecht NL, 2000, pp. 33-58

Ionones, Irones, Damascones & Structurally Related Odorants

Acyclics (Alcohols, Esters, Acids, Aldehydes)

Lactones

Sesquiterpenoid Related Odorants