1003-04-9Relevant articles and documents
Investigation of the aroma-active compounds formed in the maillard reaction between glutathione and reducing sugars
Lee, Sang Mi,Jo, Ye-Jin,Kim, Young-Suk
, p. 3116 - 3124 (2010)
Aroma-active compounds formed during the thermal reaction between glutathione (GSH) and reducing sugars were analyzed by gas chromatography-mass spectrometry (GC-MS) and GC-olfactometry (GC-O) with aroma extract dilution analysis (AEDA). Application of AEDA to glutathione Maillard reaction products (GSH MRPs) led to the identification of 19 aroma-active compounds in the thermal reaction of glutathione with glucose or fructose. In addition, the carbohydrate module labeling (CAMOLA) approach was also employed to elucidate the formation pathways for selected target sulfur aroma compounds, such as 5-methylthiophene-2-carbaldehyde and 3-methylthiophene-2-carbaldehyde, which have not been reported previously. The intact carbon skeleton of glucose via 3-deoxyhexosone is incorporated into 5-methylthiophene-2-carbaldehyde with the hydrogen sulfide of GSH. On the other hand, the formation of 3-methylthiophene2-carbaldehyde may occur via the recombination of a C-4 sugar fragment and mercaptoacetaldehyde.
Preparation method of substituted thiophene-3-one compound
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Paragraph 0054; 0062; 0067; 0072; 0077; 0082; 0087; 0092, (2018/08/04)
The invention provides a preparation method of a substituted thiophene-3-one compound, comprising: subjecting material A and material B to Michael addition reaction to obtain an addition product; subjecting the addition product to Dieckmann condensation reaction to obtain a substituted thiophene-3-one compound having a structure shown as formula (IV) that is shown in the description. The preparation method provided by the application has the advantages that using solvents and strong bases is not required, reaction materials are low in price and easy to obtain, no wastewater is produce, and therefore, the preparation method has good environmental friendliness; compared with existing preparation methods, the preparation method has a short synthetic route, can be performed under mild conditions and features good yield stability and good repeatability, which is helpful for greatly increasing total yield of the substituted thiophene-3-one compound and helpful for industrial popularization.
Method for preparing chiral diphosphines
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, (2008/06/13)
The invention concerns a method for preparing a compound of formula (1) wherein: A represents naphthyl or phenyl optionally substituted; and Ar1, Ar2independently represent a saturated or aromatic carbocyclic group, optionally substituted.
Thio-sugars. Part 10. The Nucleoside from 5-Fluoroacil and 2-Amino-2,3-dideoxy-4-thio-DL-glycero-tetrofuranose and Related Compounds
Jones, John O.,McElhinney, R. Stanley
, p. 1501 - 1517 (2007/10/02)
Another molecular combination of a chloroethylnitrosourea and a pyrimidine antimetabolite (5-fluorouracil) linked through a sugar or sugar-like moiety has been synthesised for biological testing.In this case 2-amino-2,3-dideoxy-4-thio-DL-glycero-tetrofuranose was derived from thiolan-3-one, nitrogen being introduced as azide in preference to the route involving oxime and phthalimide.Some derivatives of 3-amino-3-deoxy-4-thio-DL-erythrofuranose were prepared from trans-4-aminothiolan-3-ol, inverted by way of a fused oxazoline, but although a (5-iodouracil) nucleoside ester was obtained it proved difficult to remove the protecting groups.
Enzymes in organic syntheses. 19. Evaluation of the stereoselectivities of horse liver alcohol dehydrogenase; catalyzed oxidoreductions of hydroxy- and ketothiolanes, -thianes, and -thiepanes
Jones, J. Bryan,Schwartz, Harold M.
, p. 1574 - 1579 (2007/10/02)
The specificity of horse liver alcohol dehydrogenase (HLADH) with respect to unsubstituted five-, six-, and seven-membered ring 3- and 4-thiaketone and -thiaalcohol substrates has been examined.The enzyme is found to have a broad tolerance of the structural variations within this series.HLADH also exhibits encouraging (up to 46percent) enantiotopic and enantiomeric specifity in preparative-scale reduction and oxidation reactions of the heterocyclic ketones and alcohols respectively.
REACTIONS OF α-DIAZO KETONES. IV. S-5 PARTICIPATION AND β-ELIMINATION IN THE ACETOLYSIS OF 4-ARYLTHIO- AND 4-ARALKYLTHIO-1-DIAZO-2-BUTANONES
Rosnati, Vittorio,Saba, Antonio
, p. 211 - 214 (2007/10/02)
The acetolyses of α-diazo ketones 2a-d, bearing a thioether group on the β'-carbon have been studied in neat AcOH and in the presence of acetate.All these reactions lead to products arising from the 1,4-shift of the thioether group, normal substitution being only a secondary pathway, particularly in the case of 2d, which almost exclusively undergoes fragmentation to benzhydryl acetate and 3-oxotetrahydrothiophene.The mechanisms involved are discussed.
