5011-57-4Relevant articles and documents
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.
Optically active compound, liquid crystal compositions containing the optically active compound, and liquid crystal display device
-
, (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