59303-05-8Relevant academic research and scientific papers
Rotational Conformers of Furan and Thiophene Thioaldehyde Anion Radicals
Borghi, R.,Cremonini, M. A.,Lunazzi, L.,Placucci, G.,Macciantelli, D.
, p. 6337 - 6341 (1991)
The radical anions of the four isomeric furan and thiophene thioaldehydes have been obtained by photolysis, in an alkaline medium, of the corresponding thiols in the presence of di-tert-butyl peroxide.The same reaction also yields the four corresponding aldehyde radical anions, starting from the appropriate alcohols.The ESR spectra show that in most cases the two rotational conformers (E and Z) are present at the equilibrium.By means of appropriate methyl-substituted derivatives it has been possible to assign the structure of the two conformers.In the case of the 2-furan and 2-thiophene aldehyde anion radicals it has been found that the conformational preference is the same as that exhibited by the corresponding molecules.
Structure-Odor Correlations in Homologous Series of Mercapto Furans and Mercapto Thiophenes Synthesized by Changing the Structural Motifs of the Key Coffee Odorant Furan-2-ylmethanethiol
Schoenauer, Sebastian,Schieberle, Peter
, p. 4189 - 4199 (2018/05/01)
Furan-2-ylmethanethiol (2-furfurylthiol; 2-FFT, 1) is long-known as a key odorant in roast and ground coffee and was also previously identified in a wide range of thermally treated foods such as meat, bread, and roasted sesame seeds. Its unique coffee-like odor quality elicited at very low concentrations, and the fact that only a very few compounds showing a similar structure have previously been described in foods make 1 a suitable candidate for structure-odor activity studies. To gain insight into the structural features needed to evoke a coffee-like odor at low concentrations, 46 heterocyclic mercaptans and thio ethers were synthesized, 32 of them for the first time, and their odor qualities and odor thresholds were determined. A movement of the mercapto group to the 3-position kept the coffee-like aroma but led to an increase in odor threshold. A separation of the thiol group from the furan ring by an elongation of the carbon side chain caused a loss of the coffee-like odor and also led to an increase in odor thresholds, especially for ω-(furan-2-yl)alkane-1-thiols with six or seven carbon atoms in the side chain. A displacement of the furan ring by a thiophene ring had no significant influence on the odor properties of most of the compounds studied, but the newly synthesized longer-chain 1-(furan-2-yl)- and 1-(thiophene-2-yl)alkane-1-thiols elicited interesting passion fruit-like scents. In total, only 4 out of the 46 compounds also showed a coffee-like odor quality like 1, but none showed a lower odor threshold. Besides the odor attributes, also retention indices, mass spectra, and NMR data of the synthesized compounds were elaborated, which are helpful in possible future identification of these compounds in trace levels in foods or other materials.
Generation of thiols by biotransformation of cysteine-aldehyde conjugates with baker's yeast
Huynh-Ba, Tuong,Matthey-Doret, Walter,Fay, Laurent B.,Rhlid, Rachid Bel
, p. 3629 - 3635 (2007/10/03)
Baker's yeast was shown to catalyze the transformation of cysteine-furfural conjugate into 2-furfurylthiol. The biotransformation's yield and kinetics were influenced by the reaction parameters such as pH, incubation mode (aerobic and anaerobic), and substrate concentration. 2-Furfurylthiol was obtained in an optimal 37% yield when cysteine-furfural conjugate at a 20 mM concentration was anaerobically incubated with whole cell baker's yeast at pH 8.0 and 30 °C. Similarly to 2-furfurylthiol, 5-methyl-2-furfurylthiol (11%), benzylthiol (8%), 2-thiophenemethanethiol (22%), 3-methyl-2-thiophenemethanethiol (3%), and 2-pyrrolemethanethiol (6%) were obtained from the corresponding cysteine-aldehyde conjugates by incubation with baker's yeast. This work indicates the versatile bioconversion capacity of baker's yeast for the generation of thiols from cysteine-aldehyde conjugates. Thanks to its food-grade character, baker's yeast provides a biochemical tool to produce thiols, which can be used as flavorings in foods and beverages.
Thiazolopyrimidines and thier use as modulators of chemokine receptor activity
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, (2008/06/13)
The invention provides certain thiazolopyrimidine compound, processes and intermediates used in their preparation, pharmaceutical compositions containing them and their use in therapy.
Identification of Potent Aroma Compounds in Thermally Treated Mixtures of Glucose/Cysteine and Rhamnose/Cysteine Using Aroma Extract Dilution Techniques
Hofmann, Thomas,Schieberle, Peter
, p. 898 - 906 (2007/10/03)
Application of an aroma extract dilution analysis on extracts prepared from either thermally treated solutions (20 min, 145 °C) of glucose/cysteine (I) or rhamnose/cysteine (II) led to the identification of 2-furfurylthiol (roasty, coffee-like), 5-acetyl-2,3-dihydro-1,4-thiazine (roasty), 3-mercapto-2-butanone (sulfury, rotten), 3-mercapto-2-pentanone (catty), and 4-hydroxy-2,5-dimethyl-3(2H)-furanone (caramel-like) with the highest odor activities among the 34 odor-active volatiles detected in I. In II, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 3-hydroxy-6-methyl-2(2H)-pyranone (seasoning-like), 5-methyl-2-furfurylthiol (roasty, coffee-like), 2-furfurylthiol, and 5-acetyl-2,3-dihydro-l,4-thiazine appeared with the highest flavor dilution (FD) factors among the 18 compounds detected by HRGC/O. Among the flavor compounds identified, 2-propionyl-2-thiazoline is reported for the first time among the flavors of Maillard model reactions or foods, respectively. The odorant elicited an intense roasty, popcorn-like odor at the low odor threshold of 0.07 ng/L in air.
