5011-57-4Relevant academic research and scientific papers
Structure-odor correlations in homologous series of alkanethiols and attempts to predict odor thresholds by 3d-qsar studies
Polster, Johannes,Schieberle, Peter
, p. 1419 - 1432 (2015/03/05)
Homologous series of alkane-1-thiols, alkane-2-thiols, alkane-3-thiols, 2-methylalkane-1-thiols, 2-methylalkane-3-thiols, 2-methylalkane-2-thiols, and alkane-1,??-dithiols were synthesized to study the influence of structural changes on odor qualities and odor thresholds. In particular, the odor thresholds were strongly influenced by steric effects: In all homologous series a minimum was observed for thiols with five to seven carbon atoms, whereas increasing the chain length led to an exponential increase in the odor threshold. Tertiary alkanethiols revealed clearly lower odor thresholds than found for primary or secondary thiols, whereas neither a second mercapto group in the molecule nor an additional methyl substitution lowered the threshold. To investigate the impact of the SH group, odor thresholds and odor qualities of thiols were compared to those of the corresponding alcohols and (methylthio)alkanes. Replacement of the SH group by an OH group as well as S-methylation of the thiols significantly increased the odor thresholds. By using comparative molecular field analysis, a 3D quantitative structure-activity relationship model was created, which was able to simulate the odor thresholds of alkanethiols in good agreement with the experimental results. NMR and mass spectrometric data for 46 sulfur-containing compounds are additionally supplied.
Identification and Synthesis of 2-Heptanethiol, a New Flavor Compound Found in Bell Peppers
Simian, Herve,Robert, Fabien,Blank, Imre
, p. 306 - 310 (2007/10/03)
2-Heptanethiol was identified for the first time as a constituent of red and green bell pepper extracts. The chemical structure of this new aroma compound was proposed on the basis of mass spectra and retention indices and confirmed by chemical synthesis and nuclear magnetic resonance spectroscopy measurements. Its aroma properties were described as sulfury, onion-like, and vegetable-like, reminiscent of bell pepper at lower concentrations, with an orthonasal detection threshold of 10 μg/L of water. No differences in odor note and threshold value were observed for the enantiomeric forms, which were prepared from enantiopure 2-heptanol by tosylation, followed by thioacetylation and reduction, giving the target thiol enantiomers.
Optically active compound, liquid crystal compositions containing the optically active compound, and liquid crystal display device
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, (2008/06/13)
?I! An optically active compound of the formula (1), STR1 wherein R1 is a linear alkyl group, each of X1 and X2 is a hydrogen atom or one of X1 and X2 is a hydrogen atom and the other is a fluorine atom, each of Y1 and Y2 is a hydrogen atom or one of Y1 and Y2 is a hydrogen atom and the other is a fluorine atom, m is an integer of 3 to 10, and C* is an asymmetric carbon atom, ?II! an anti-ferroelectric liquid crystal composition consisting essentially of the optically active compound of the above formula (1) and a compound of the formula (2), STR2 and ?III! a ferrielectric liquid crystal composition consisting essentially of the optically active compound of the formula (1) and a compound of the formula (3). STR3
Nuclear Heptylation of Benzene and Naphthalene and Cyclopentylation of Toluene
Badr, M. Z. A.,El-Naggar, G. M.,Aly, M. M.,Fahmy, A. M.
, p. 961 - 964 (2007/10/02)
Thermal decomposition of 1-, 2-, 3- and 4-heptyltoluene-p-sulphonates in the presence of aromatic substrates like benzene or naphthalene at 130-35 deg, affords differently substituted α- and β-isomers in the case of naphthalene.Skeletal isomerisation of the alkyl group is observed where different isomeric 1-, 2-, 3- and 4-heptyl-aromatics are obtained.Also thermal decomposition of cyclopentylmethane sulphonate in the presence of toluene at 130-35 deg, furnishes the corresponding o-, m- and p-substituted toluenes.The isomers have been identified and estimated quantitatively by GLC.
