3-Methyl-4-octanolide

Some representatives of y-lactones are y-valerolactone 150, y-decalactone 151 with peach-like flavour, (Z)-6-dodecen-4-olide 152, 3-methyl-4-octanolide (whiskey lactone) 153 and 3-hydroxy-4,5-dimethyl-2(51T)-furanone (sotolone) 154 (Structure 4.46), found in fenugreek, coffee and sake [1-4, 21-23, 62]. 

Methyl-4-octanolide (55g) (437, 608), also known under the name Whisky lactone , exists in two diastereoisomeric forms. The aroma of the cw-lactone, which has a higher odor threshold value (0.79 ppm), is more fragrant than that of the tm j-lactone (odor threshold 0.067 ppm)... 

Masuda M, Nishimura K 1981 Absolute configurations of quercus lactones, (3R,4i )- and (3S,45)-3-methyl-4-octanolide, from oak wood and chiroptical properties of mono-cyclic y-lac-tones. Chem Lett 1333-1336... 

Other important odorous components of foods are fragrant lactones derived from branched aliphatic hydroxycarboxyhc acids. The trivial names are normally preferred. An important component of the aroma of wines and spirits aged in oak barrels (such as whisky) is the so-called whisky lactone, 5-butyl-4-methyl-4,5-dihydro-3H-furan-2-one (3-methyloctano-4-lactone, 3-methyl-4-octanolide or 4-butyl-3-methylbutyrolactone), also known as cognac or oak lactone, which can exist in four stereoisomers, ofwhich the (3S,4S)-isomer (8-106) predominates. In brandy, for example, the content of the (Z)-isomers, (3R,4R)- and (3S,4S)-isomers, that have a desirable flavour, ranges between 30 and 247 xg/l. The (E)-isomers, (3S,4R)- and (3E,4S)-isomers, are found at a concentration of 115-736 p.g/1. The precursor of the (3S,4S)-isomer in oak wood... 

OCTANOL (FCC) see OEIOOO OCTANOLIDE-1,4 see OCEOOO 3-OCTANOL, 3-METHYL- see MND050... 

Ethyl-2-methyl-3-hydroxyoctanoic acid, ethyl ester, 37,39,40 4-Ethyl-2-methyl-l,4-octanolide, 37,... 

Fig. 13.9. Structure of the main volatile compounds identified in extracts of non-toasted oak wood I, methyl-octalactone or methyl-4-octanolide, II, eugenol IE, vanillin IV, syringaldehyde V, coniferaldehyde VI, sinapaldehyde (Chatonnet, 1995)...

HL 8-Membered lactone 8-OL 8-Octanolide HDL 16-Hexadecanolide MVL a-Methyl-5-valerolactone UDL 11-Undecanolide aMCL a-Methyl-e-caprolactone 8-DL 5-Decalactone y-BL y-Butyrolactone y-CL y-Caprolactone y-VL y-Valerolactone 5-VL 6-Valerolactone ... 

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