57674-17-6Relevant academic research and scientific papers
Stable isotope labeled 2 - methoxy -3 - isobutyl pyrazine synthesis method (by machine translation)
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Paragraph 0013; 0034; 0038; 0042; 0046, (2018/09/12)
The invention relates to stable isotope labeled 2 - methoxy - 3 - isobutyl pyrazine synthetic method, bright ammonia amide hydrochloride as the raw material, after cooling with the glyoxal solution reaction, to obtain the 2 - hydroxy - 3 - isobutyl pyrazine, 2 - hydroxy - 3 - isobutyl pyrazine by the chlorinated reaction to obtain a pale yellow liquid 2 - chloro - 3 - isobutyl pyrazine, re-and stable isotope labeled methanol reaction, get colorless transparent liquid stable isotope-labeled 2 - methoxy - 3 - isobutyl pyrazine. Compared with the prior art, the process of the invention the procedure is short, the operation is simple, few by-products, the isotope abundance is not diluted and the like. (by machine translation)
New insights into the synthesis and characterization of 2-methoxy-3-alkylpyrazines and their deuterated isotopologues
Schmarr,Sang,Ganss,Koschinski,Meusinger
scheme or table, p. 438 - 440 (2012/07/13)
A previously described synthetic route for preparation of 2-methoxy-3-alkylprazines (MPs) based on condensation of glyoxal with an α-amino acid amide, followed by methylation with iodomethane yields 3-alkyl-1-methyl-1H-pyrazin-2-ones (N-methyl derivatives), rather than the designated 2-methoxy-3-alkylpyrazines (O-methyl derivatives). Despite similar nuclear magnetic resonance and mass spectral properties, gas chromatographic (GC) retention indices differ significantly, indicating chemical difference. With the example of 3-sec-butyl-1-methyl-1H-pyrazin-2-one and its 3-sec-butyl-1-[2H3]methyl-1H-pyrazin-2-one isotopologue, the position of the methyl group introduced could be assigned unambiguously, using heteronuclear multiple bond correlation (HMBC) NMR experiments. For future characterization, the spectroscopic (NMR, EI+MS) as well as GC retention index data on two stationary phases of the most aroma relevant MPs and their deuterated isotopologues are summarized. Copyright
New approach to asymmetrically substituted methoxypyrazines, derivatives of wine flavors
Candelon, Nicolas,Shinkaruk, Svitlana,Bennetau, Bernard,Bennetau-Pelissero, Catherine,Dumartin, Marie-Laurence,Degueil, Marie,Babin, Pierre
scheme or table, p. 2463 - 2469 (2010/06/14)
An original synthetic route to asymmetrically substituted methoxypyrazine (MP) derivatives is described. The first step of the synthesis is achieved by condensation of 1,2-aminoalcohols with Boc-protected aliphatic aminoacids followed by cycloimine formation and aromatization via chlorination. Introduction of methoxy group was then achieved by alkoxy-de-halogenation. The use of primary or secondary aminopropanol enabled the direct and selective introduction of methyl group, in 5- or 6-position, which can be easily functionalized. Aromatization of diketopiperazine, prepared from l-valine and l-glutamic acid dimethyl ester, made possible a direct introduction of a functionalized alkyl chain. These reactions are also suitable for the synthesis of naturally-occurring MPs such as wine flavor components and biologically active substances.
