Results 221 to 230 of about 13,234 (272)
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Vibrational spectra of [1H4]pyrazine and [2H4]pyrazine
Journal of the Chemical Society, Faraday Transactions 2, 1985Infrared and Raman spectra of [1H4]pyrazine and [2H4]pyrazine have been reinvestigated and a general assignment of all the observed bands is proposed which modifies some previous assignments of fundamental vibrations. The present assignment satisfies the isotopic product rule for i.r.- and Raman-active fundamentals.
Juan F. Arenas +4 more
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Proceedings of the Royal Society of London. Series B: Biological Sciences, 1990
Of the various types of alerting signals found in nature, odours are the least well understood. The worldwide distribution of pyrazines in plants, insects, terrestrial vertebrates, marine organisms, fungi and bacteria suggests that they are of special significance.
A, Woolfson, M, Rothschild
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Of the various types of alerting signals found in nature, odours are the least well understood. The worldwide distribution of pyrazines in plants, insects, terrestrial vertebrates, marine organisms, fungi and bacteria suggests that they are of special significance.
A, Woolfson, M, Rothschild
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Synthesis of tetrasubstituted pyrazines and pyrazine N-oxides
Tetrahedron Letters, 2010Abstract An efficient synthesis of tetrasubstituted unsymmetrical pyrazines and their related pyrazine N-oxides has been developed from commercially available 2-chloro-3-methylpyrazine. The procedure and scope of these synthesis routes are described.
Jae Uk Jeong +3 more
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2,3,5,6-Tetrakis(phenoxymethyl)pyrazine and 2,3,5,6-tetrakis(phenylsulfanylmethyl)pyrazine
Acta Crystallographica Section C Crystal Structure Communications, 2007The title compounds, C(32)H(28)N(2)O(4), (I), and C(32)H(28)N(2)S(4), (II), respectively, are tetrasubstituted pyrazines and both possess C(i) symmetry. They differ only in the hetero atom (X) of the -CH(2)XPh side-arm substituents: X = O in (I) and S in (II).
Assoumatine T +2 more
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Vapour and crystal spectra in polarized light of pyrazine-d0, cis pyrazine-d2 and pyrazine-d4
Spectrochimica Acta, 1964Abstract The infrared spectra of pyrazine-d0, cis pyrazine-d2 and pyrazine-d4 have been measured between 4000 and 400 cm−1. The spectra have been obtained in the vapour and solid states. The dichroic behaviour of the bands has been measured on polycrystalline fully oriented samples.
S. Califano, G. Adembri, G. Sbrana
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Pyrazine chemistry. Part 9. Oxygenation of pyrazines and pyrimidines
Journal of the Chemical Society, Perkin Transactions 1, 1979Singlet oxygen adds to certain substituted pyrazines and pyrimidines to form the endo-peroxides in high yield. The peroxides derived from the pyrazines are often stable compounds. 2,5-Diethoxy-3,6-dimethyl-3,6-epidioxy-3,6-dihydropyrazine can be reduced to the corresponding diol with sodium borohydride, whilst the parent pyrazine is regenerated by ...
Janet L. Markham, Peter G. Sammes
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C R C Critical Reviews in Food Technology, 1973
Because of their unique organoleptic properties, pyrazine compounds have recently been receiving increased attention in food related areas. Numerous compounds have been detected in foods, and others have been synthesized and promoted as flavoring agents. This review provides the reader with a composite appreciation of pyrazines in foods. A total of ten
Joseph A. Maga +2 more
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Because of their unique organoleptic properties, pyrazine compounds have recently been receiving increased attention in food related areas. Numerous compounds have been detected in foods, and others have been synthesized and promoted as flavoring agents. This review provides the reader with a composite appreciation of pyrazines in foods. A total of ten
Joseph A. Maga +2 more
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ChemInform Abstract: Pyrazine. Syntheses of Naturally Occurring Pyrazines
ChemInform, 1997AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
A. OHTA, Y. AOYAGI
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Pyrazines: occurrence, formation and biodegradation
Applied Microbiology and Biotechnology, 2009Pyrazines are a class of compounds that occur almost ubiquitously in nature. Pyrazines can be synthesised chemically or biologically, and are used as flavouring additives. The major formation of pyrazines occurs during heating of food. There is very little information available on the degradation of these compounds. In humans and animals, pyrazines are
Rudolf, Müller, Sugima, Rappert
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