Ethyl (S)-(+)-3-methyl-2-oxo-pentanoate - a typical walnut note, accompanied by a walnut-husk, pungent, ethereal, slightly fruity odor Ref: Snowden , et al., United States Patent 5,952,292, September 14, 1999 & Snowden , et al., United States Patent 6,159,929, December 12, 2000

Ethyl (R)-(-)-3-methyl-2-oxo-pentanoate - typical walnut note, but its odor is more pungent, more dry, less powerful and does not possess the fruity-apple note present in the (S)-isomer Ref: Snowden , et al., United States Patent 5,952,292, September 14, 1999 & Snowden , et al., United States Patent 6,159,929, December 12, 2000

Ionones, Irones, Damascones & Structurally Related Odorants

Acyclics (Alcohols, Esters, Acids, Aldehydes)

Lactones

Sesquiterpenoid Related Odorants