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Olfactory Properties (olfactory + property)
Selected AbstractsOlfactory properties of straight-chain undecan -x- ones, undecan -x- ols (x = 2,6) and their derivativesFLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2008Julia Gibka Abstract A series of undecan -x- ones (x = 2,6) was used as starting material in the synthesis of ethylene and propylene acetals, undecanols and their acetates. Undec-3-yl and undec-6-yl acetates, ethylene acetal of undecan-3-one and propylene acetals of undecan -x- ones (x = 2,5) have not yet been described. The odour properties for all the synthesized compounds have been determined. They have pleasant, fruity, herbaceous odours that can be described as food odours. The most valuable groups of compounds are ketones and their acetals, which have intense, pleasant, fruity, vegetable, spicy or herbaceous odours. In the case of alcohols, mild odours dominate with fruity, wooden or floral notes. All acetates have faint or mild fatty-soapy odours. A correlation between the structure of the studied compounds and their odours has been found. Fruity odours appear among ketones and alcohols when a shift of the functional group from position 2 to the middle of the molecule occurs. In the studied ethylene and propylene acetals this shift strengthens their vegetable and spicy odours, respectively. Copyright © 2008 John Wiley & Sons, Ltd. [source] Unexpected Tethering in the Synthesis of Methyl-Substituted Acetyl-1-oxaspiro[4.5]decanes: Novel Woody,Ambery Odorants with Improved Bioavailability,EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 2 2008Philip Kraft Abstract To study the olfactory properties of spirocyclic analogs of Iso Gamma (3) with improved water solubility and bioavailability, it was envisaged to spiroannulate 1-acetyl-1,2-dimethylcyclohexanone at the 4-position with a 3,3-dimethyltetrahydrofuran-2-yl moiety that would mimic the polarity of the double bond by its ether function. 3,3-Dimethyl-4-methylenehex-5-en-1-ol (9) was prepared by copper(I)-mediated 1,4-conjugate addition of the Grignard reagent of chloroprene (7) to 3-methylbut-2-enal with subsequent LAH reduction. However, the Diels,Alder reaction of diene 9 with (E)-3-methylpent-3-en-2-one in the presence of Me2AlCl unexpectedly provided exclusively the undesired meta adduct 10, as was discovered after cyclization to 11 with MeSO3H. The wrong selectivity was due to a tethering effect of the Lewis acid, and this could be evaded by changing the carbonyl function of the dienophile to a hydroxy group. Thereby the (5,R*,7,S*,8,S*)-configured 1-(4,,4,,7,,8,-tetramethyl-1,-oxaspiro[4.5]decan-7,/8,-yl)ethan-1-ones 11 and 14, as well as the like -configured 1-(4,,4,,7,-trimethyl-1,-oxaspiro[4.5]decan-7,/8,-yl)ethan-1-ones 16 and 19, were prepared selectively and studied for their odor characters, threshold values, and octanol/water partition coefficients. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Multidimensional scaling of fragrances: A comparison between the verbal and non-verbal methods of classifying fragrances1JAPANESE PSYCHOLOGICAL RESEARCH, Issue 1 2004Takahiro Higuchi Abstract:,Higuchi, Shoji, and Hatayama (2002) selected nine sense-descriptive adjectives (e.g., sweet, clear) to describe the olfactory properties of fragrances. In order to clarify the ability of these adjectives to classify fragrances, the present study used a non-verbal sorting of fragrances that has been widely accepted in previous studies as a method of classifying fragrance. Interfragrance similarities obtained from the non-verbal sorting were then compared with those obtained from the adjective rating based on a two-dimensional spatial configuration of fragrances created by a multidimensional scaling (MDS) analysis. The similarities of the two MDS configurations, obtained from the verbal and non-verbal sorting, were estimated by the correlation of interfragrance distances on the spatial configuration. The correlation coefficient was 0.61, indicating that the ability of the sense-descriptive adjectives to classify fragrances is nearly the same as that of the non-verbal sorting. [source] Review Article: Fragrance technology for the dermatologist , a review and practical applicationJOURNAL OF COSMETIC DERMATOLOGY, Issue 3 2010Claudia S Cortez-Pereira MSc Summary Cosmetic product development has increased in recent years. The value of a product is emphasized in its safety and effectiveness. The stability study in the context of product quality evaluation during shelf life becomes primordial to guarantee the integrity of the physical, chemical, and olfactory properties. In this study, aromatic compositions had been submitted to the stability normal test, at low temperature (4.0 ± 2.0 °C), at room temperature (22.0 ± 2.0 °C), and in oven (45.0 ± 2.0 °C). The compositions were analyzed at 15, 30, 60, and 90 days versus a fresh aromatic composition 48 h after preparation, in which the organoleptic characteristics and pH value were evaluated besides undertaking sensory evaluation. The results demonstrated that at the high temperature (45.0 ± 2.0 °C), in which the oxidative processes of the fragrance components are accelerated, the cosmetic preparation "A" was chosen because it showed more acceptable physical,chemical properties and in terms of sensory evaluation of perfume character and intensity was approved for commercial use. [source] Disila-Okoumal: A Silicon Analogue of the Ambergris Odorant OkoumalCHEMBIOCHEM, Issue 12 2007Matthias W. Büttner Abstract Two-fold sila-substitution (C/Si exchange) in the saturated ring of the tetrahydronaphthalene skeleton of the ambery odorant okoumal (5) provides disila-okoumal (6). The okoumal isomers 5,a,d were synthesized from 1-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-2-naphthyl)ethanone (7), and the silicon analogues 6,a,d were synthesized from 1-(5,5,8,8-tetramethyl-5,8-disila-5,6,7,8-tetrahydro-2-naphthyl)ethanone (8). Detailed olfactory properties of 5,a,d and 6,a,d are reported, together with the respective threshold values. All enantiomers of okoumal and disila-okoumal exhibit typical ambery odor notes with woody facets, as is characteristic of okoumal and karanal, but a stereocenter at the 2-position was found to be of utmost importance for the odor thresholds; the lowest value of 0.31 ng per L air was measured for the 2R -configured silicon compounds 6,a and 6,c. [source] Woody Pretzels: Spirocycles from Vetiver to Patchouli and Georgywood®CHEMISTRY & BIODIVERSITY, Issue 6 2008Philip Kraft Abstract This review, including new experimental results, is the summary of a talk at the RSC/SCI conference ,flavours & fragrances 2007' in London, Imperial College, 24,26 September, 2007. Though the third dimension of the receptor models of J.,E. Amoore rarely was exceeding 4,Å, the world of woody odorants such as (+)-cedrol (3; cedarwood), (,)-khusimone (4; vetiver), and (,)-patchoulol (5; patchouli) is anything but flat. Any tricyclic skeleton with a zero-bridge contains a spirocyclic ring system determining its 3D structure, so spirocycles (spira, Lat. pretzel) are the fastest access to the third dimension. In the vetiver family, a spirocyclic mimic 9 of (,)-khusimone (4) was first discovered by chance by Büchi in 1976, and also by chance, we obtained another system, 12, with a characteristic vetiver smell by tandem- Rupe,Nazarov reaction of alkyne diols. A 5-Å distance between a quaternary C-atom and a carbonyl group (or alternative HB acceptor) with an , -methyl or methylene branching is proposed to be the key to their vetiver odor. Upon scale-up of one of these odorants, 24, we discovered a very powerful (0.067,ng/l) impurity with a most typical patchouli scent: the spirocyclic, sterically crowded hydroxy ketone 33 , a most unusual structure for a patchouli odorant. Several spirocyclic hydroxy ketone analogs, also with inverted ring systems such as in 70 and 84, provided new insights into the structure,odor correlation of this family. A superposition analysis indicated the carbonyl function of the hydroxy ketone to overlay on the geminal dimethyl motive of (,)-patchoulol. And indeed, the corresponding hydroxy ketone of patchoulol, 59, synthesized in 13 steps from Cyclal C (63), also emanated a patchouli odor. Finally, the synthesis and olfactory properties of twelve rigid spirocyclic analogs, 95,97, 99,102, and 106,110, of Georgywood® (91) are presented that highlight stereochemical requirements for woody odorants and raise doubts about an , -helical binding motive postulated by Hong and Corey. 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