P-Menthan-3-one

Kopke X Mosandl A, Stereoisomeric flavor compounds. Part LIV 8-Mercapto-p-menthane-3-one -optically pure stereoisomers and chirospecific analysis, Z Lebensm Unters Forsch 194 372—376, 1992. 

Of the few known terpene compounds that contain heteroatoms such as nitrogen or sulfur, the thiol 8-mercapto-p-menthan-3-one described below has qualitatively important applications as a fragrance and flavor substance. The second thiol, -p-menthene-8-thiol, is described because its odor threshold value is far lower than that of most other fragrance and flavor materials. 

Mercapto-p-menthan-3-one has been identified as a constituent of Buchu leaf oil [6] and is a very useful substance in black currant and tropical flavours. The reaction of pulegone with hydrogen sulfide in an alkaline medium results in 8-mercapto-p-menthan-3-one formation (Scheme 13.6). 

Scheme 13.6 Chemical synthesis of 8-mercapto-p-menthan-3-one from pulegone...

Buchu (+)-trans-8-Mercapto- p-menthan-3-one Black currant flavoirrs... 

SYNS FEMA No. 2667 l-p-MENTHAN-3-ONE 1-MENTHONE (FCC) p-MENTHONE trans-MENTH-ONE trans-5-METHYI 2-(l-METFTYLETHYL)-CYCLOHEXANONE... 

C10H18O p-menthan-3-one racemic 1074-95-9 480.98 42.060 2 20841 C10H18O5 diethylene glycol diglycidyl ether 4206-61-5 509.90 44.836 2... 

CIC Ethyl butyrate contribute to the fruity, estery note linalool, alpha-terpineol, citronellol and damascenone support the floral, fruity ripe character and 1,8-cineol imparts the freshness. 4-methoxy-2-methyl-2-mercapto butane is responsible for typical catty sulphurous black currant note. Extracts of the black currant buds are more green, herbaceous but they also contain the sulphurous CIC. A similar note, 8-mercapto-p-menthan-3-one has been identified in buchu oil and is often used to imitate the catty black currant aspect. 

Owing to their characteristic minty-fruity notes, reminiscent of blackcurrants, buchu leaf oils are well appreciated in the composition of flavourings and fragrances. 8-Mercapto-p-menthan-3-one and its thiolacetate have been described by Sundt et al. [98] and simultaneously by Lamparsky et al. ]99]as impact flavouring compounds of the flavour of cassis. They have so far not been identified in blackcurrant. All four stereoisomers of 8-mercapto-p-menthan-3-one exhibit distinct and characteristic sensory impressions ]100]. 

A. Mosandl, T. Kbpke and W. Bensch. Stereoisomeric Elavour compounds. EXIT Structure elucidation of 8-mercapto-p-menthan-3-one isomers. Tetrahedron Asymm., 4, 651-654 (1993). 

Europe 1 for the related substance 2-mercapto-3-USA ND butanol (No. 546) (Coxetal., 1974) is Japan ND 35 000 times the estimated daily intake of cIs- and frar S-mercapto-p-menthan-3-one when used as a flavouring agent. 

Fourteen members of this group of flavouring substances, ethane-1,1 -dithiol (No. 1660), 4-mercapto-2-pentanone (No. 1670), diisopentyl thiomalate (No. 1672), cis- and frans-mercapto-p-menthan-3-one (No. 1673), 2,4,6-trithiaheptane (No. 1684), ( )-2,8-epithio-c/s-p-menthane (No. 1685), mixture of 3,6-diethyl-1,2,4,5-tetrathiane and 3,5-diethyl-1,2,4-trithiolane (No. 1687), ( )-3-(methylthio)heptanal (No. 1692), ethyl methyl disulfide (No. 1693), ethyl propyl trisulfide (No. 1695), methyl isopentyl disulfide (No. 1696), butyl ethyl disulfide (No. 1698), allyl propyl disulfide (No. 1700) and bis(1-mercaptopropyl)sulfide (No. 1709), have assay values of <95%. Information on the safety of the secondary components of these 14 compounds is summarized in Annex 5 (Summary of the safety evaluation of secondary components for flavouring agents with minimum assay values of less than 95%). The secondary component of diisopentyl thiomalate, diisopentyl thiotartronate, is expected to share the same metabolic fate as the primary substance. The secondary components of frans-mercapto-p-menthan-3-one, piperitone (No. 435) and a-terpineol (No. 366), are expected to undergo rapid absorption, distribution, metabolism and excretion and were evaluated at previous... 

CAS 491-07-6 EINECS/ELINCS 207-727-4 Synonyms cis-p-Menthan-3-one cis-5-Methyl-2-(1-methylethyl) cyclohexanone... 

R,4S)-(-)-p-Menthan-3-one. See l-Menthone cis-p-Menthan-3-one. See Isomenthone DL-p-Menthan-3-one. See DL-Menthone L-Menthan-3-one l-p-Menthan-3-one. See I-Menthone p-Menthanone... 

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