- Hydroxycinnamoyl Glucose and Tartrate Esters and Their Role in the Formation of Ethylphenols in Wine
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Synthesized p-coumaroyl and feruloyl l-tartrate esters were submitted to Brettanomyces bruxellensis strains AWRI 1499, AWRI 1608, and AWRI 1613 to assess their role as precursors to ethylphenols in wine. No evolution of ethylphenols was observed. Additionally, p-coumaroyl and feruloyl glucose were synthesized and submitted to B. bruxellensis AWRI 1499, which yielded both 4-ethylphenol and 4-ethylguaiacol. Unexpected chemical transformations of the hydroxycinnamoyl glucose esters during preparation were investigated to prevent these in subsequent synthetic attempts. Photoisomerization gave an isomeric mixture containing the trans-esters and undesired cis-esters, and acyl migration resulted in a mixture of the desired 1-O-β-ester and two additional migrated forms, the 2-O-α- and 6-O-α-esters. Theoretical studies indicated that the photoisomerization was facilitated by deprotonation of the phenol, and acyl migration is favored during acidic, nonaqueous handling. Preliminary LC-MS/MS studies observed the migrated hydroxycinnamoyl glucose esters in wine and allowed for identification of feruloyl glucose in red wine for the first time.
- Hixson, Josh L.,Hayasaka, Yoji,Curtin, Christopher D.,Sefton, Mark A.,Taylor, Dennis K.
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p. 9401 - 9411
(2016/12/23)
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- Protease inhibitors and their pharmaceutical uses
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The present invention refers to synthetic protease inhibitors having an axis of symmetry C2 or pseudo-C2 characterised by possessing, in the central portion: (1) preferably, a dihydroxyethylene function, which is isosteric with a peptidic bond; (2) a peptidemimetic bridge between the two nitrogens of the main chain and (3) radicals capable of mimetising amino acids. These new protease inhibitors are a base for the preparation of anti-viral formulations capable of inhibiting HIV virus proliferation.
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