90180-88-4Relevant academic research and scientific papers
Elucidation of the 1,3-sulfanylalcohol oxidation mechanism: An unusual identification of the disulfide of 3-sulfanylhexanol in sauternes botrytized wines
Sarrazin, Elise,Shinkaruk, Svitlana,Pons, Monique,Thibon, Cecile,Bennetau, Bernard,Darriet, Philippe
body text, p. 10606 - 10613 (2011/05/11)
A four-step purification method was developed to isolate a citrus odorant detected by gas chromatography-olfactometry (GC-O), which was apparently specific to Sauternes botrytized wines. A fragmentation pattern of the odorant was obtained by multidimensional gas chromatography- mass spectrometry- olfactometry (MDGC-MS-O). The exact mass measurement was used to determine its elemental formula as C6H12OS. On the basis of these data, the unusual structure of 3-propyl-1,2-oxathiolane was synthesized and characterized for the first time. This confirmed its identification. Its occurrence in Sauternes wine extracts was demonstrated to result from the thermal oxidative degradation of 3-sulfanylhexanol disulfide (3,3'-disulfanediyldihexan-1-ol) in the GC injector. This disulfide was synthesized and then firmly identified for the first time in Sauternes wine. Although the presence of 3-sulfanylhexanol oxidation products had previously been reported in natural extracts (but not wine), the full oxidation pathway from 3-sulfanylhexanol to 3-propyl-γ-sultine via 3,3'- disulfanediyldihexan-1-ol was clearly established for the first time. Because the disulfide has mainly been detected in Sauternes botrytized wines, this finding suggested a singular reactivity of 3-sulfanylhexanol in botrytized wines, thus opening up a wide range of new opportunities in wine chemistry.
Determination and isolation of a thioesterase from passion fruit (Passiflora edulis Sims) that hydrolyzes volatile thioesters
Tapp, Edward J.,Cummins, Ian,Brassington, David,Edwards, Robert
experimental part, p. 6623 - 6630 (2010/04/06)
Volatile organosulfur compounds (VOSCs) are high impact aroma chemicals characteristic of tropical fruits which are active as both free thiols and the respective thioesters. Using a simple and sensitive colorimetric enzyme assay, a thioesterase activity toward VOSCs has been identified in ripening purple passion fruit (Passiflora edulis Sims). The assay was based on determining the release of free thiols from 2-methyl-3-furanthiol acetate using Ellman's reagent. The major thioesterase in the fruit was found to be a wall-bound protein in the mesocarp. The extracted enzyme activity was purified 150-fold and shown to be associated with a 43 kDa monomeric serine hydrolase which was selectively labeled with a fluorophosphonate suicide probe. MS-MS sequencing identified the thioesterase as a class 13 glycoside hydrolase, most similar to pectin acetylesterase, an enzyme involved in cell wall modifications in the peel of a number of fruit. Our results suggest that cell wall hydrolases in tropical fruit may have additional useful roles in biotransforming VOSCs.
Intramolecular sulfur transfer in N-enoyl oxazolidine-2-thiones promoted by Bronsted acids. Practical asymmetric synthesis of β-mercapto carboxylic acids and mechanistic insights
Palomo, Claudio,Oiarbide, Mikel,Lopez, Rosa,Gonzalez, Pedro B.,Gomez-Bengoa, Enrique,Saa, Jose M.,Linden, Anthony
, p. 15236 - 15247 (2007/10/03)
The ability of Bronsted acids alone to efficiently promote the sulfur transfer process in N-enoyl oxazolidine-2-thiones to give β-mercapto carbonyl derivatives is demonstrated. The reactions proceed with essentially perfect diastereocontrol for a range of alkyl-substituted N-enoyl oxazolidine-2-thiones (d.r. regularly above 98:2) and high selectivity for most aryl-substituted counterparts (d.r. typically above 92:8). Importantly, the reaction works remarkably well in β,β-disubstituted N-enoyl oxazolidine-2-thiones as well, giving rise to quaternary C-S stereocenters in selectivities usually above 95:5. The relative efficiency of a range of acids (trifluoroacetic, difluoroacetic, acetic, triflic) is assessed showing TFA and TfOH as the most efficient and acetic acid as a totally inefficient reaction promoter. The new procedure complements the Lewis acid promoted reaction previously described by our group in two aspects: First, stereodivergent results are obtained for the Lewis acid or Bronsted acid promoted reactions of β,β-disubstituted enoyl compounds. Second, while the Bronsted acid promoted reactions are stereospecific, providing a good correlation between the substrate E/Z configuration and products stereochemistry, the reactions mediated by Lewis acids (BF3/OEt2) provide invariant d.r. values regardless of the E/Z composition of the starting olefin. The synthetic value of the method is illustrated by (a) removal of the oxazolidinone moiety from the rearranged products under reducing conditions (NaBH4, H 2O-THF) which yields β-mercapto alcohols and (b) treatment with Sm(OTf)3 in MeOH which affords the corresponding β-mercapto carboxylic esters, both categories of compounds being isolated in up to 97% ee. Remarkably, the method constitutes the first general approach to highly enantioenriched building blocks bearing a quaternary C-S stereocenter. On the other hand, spectroscopic and inhibition experiments are carried out that demonstrate the participation of protons also in the Lewis acid promoted reactions. Finally, the computational studies carried out at the B3LYP/6-31G* level give support for an activation of the substrate enoyl by complexation with two molecules of either the Bronsted or Lewis acid and serve to explain the stereochemical outcome of the reactions.
Fragrance precursors
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, (2008/06/13)
The invention relates to fragrance precursors, In particular, the invention relates to the use of several classes of compounds which may act as fragrance precursors, e,g., in cosmetic products such as deodorants and antiperspirants and in laundry products such as detergents and fabric softners. These compounds are odorless, but upon contacting the skin as example, in skin care compositions or in personal care compositions, produce fragrances. The compounds also produce fragrances when used in the presence of lipases, e.g. as used in (laundry) detergents, thus providing a prolongation of the fabric scenting effect. The compounds under consideration are compounds of the formula I: The substituents are defined in the specification.
A new one-step strategy for the stereochemical assignment of acyclic 2- and 3-sulfanyl-1-alkanols using the CD exciton chirality method
Weckerle, Bernhard,Schreier, Peter,Humpf, Hans-Ulrich
, p. 8160 - 8164 (2007/10/03)
A new one-step strategy is described for the stereochemical assignment of acyclic 2- and 3-sulfanyl-1-alkanols using the CD exciton chirality method. Using the 9-anthroate chromophore for the derivatization of both functional groups, the resulting bisignate CD curves unequivocally allow the determination of the stereochemistry from a single CD measurement. The usefulness of the new method is demonstrated using synthesized optically pure 3-sulfanyl-1-hexanols and 2-sulfanyl-1-hexanols as model compounds. The developed microscale method is also useful for the stereochemical assignment of 1,2- and 1,3-diols. To our knowledge this is the first application of the CD exciton chirality method to acyclic 2- and 3-sulfanyl-1-alkanols.
Oxidation of 3-sulfanyl-alcohols with sodium metaperiodate: New synthesis of sultines
Yolka,Fellous,Lizzani-Cuvelier,Loiseau
, p. 991 - 992 (2007/10/03)
A simple and highly efficient method for preparation of sultines by oxidation of 3-sulfanyl-alcohols with sodium metaperiodate is describe.
CHIRALE, SCHWEFELHALTIGE AROMASTOFFE DER GELBEN PASSIONSFRUCHT (PASSIFLORA EDULIS F. FLAVICARPA). DARSTELLUNG DER ENANTIOMEREN UND ABSOLUTE KONFIGURATION
Heusinger, Georg,Mosandl, Armin
, p. 507 - 510 (2007/10/02)
3-Methylthio-hexane-1-ol and 2-methyl-4-propyl-1,3-oxathiane, chiral S-containing aroma substances of the yellow passion fruit are resolved to enantiomers and absolute configurations are elucidated.
Enantioselective Synthesis of (+)- and (-)-cis-2-methyl-4-propyl-1,3-oxathiane and their Olfactive Properties
Pickenhagen, Wilhelm,Broenner-Schindler, Helene
, p. 947 - 952 (2007/10/02)
The enantioselective synthesis of (+)- and (-)-cis-2-methyl-4-propyl-1,3-oxathiane 8 and 9 from (E)-2-hexen-1-ol (1) as common starting material is described.The two enantiomeric forms exhibit different organoleptic properties.
