Tag: M.W=50-100

Narziss, L. published the artcileVolatile substances formed during malt and beer production, especially those formed by heating the product. Part 1. Analysis, identification and effects on aroma, Application of 4,5-Dimethyloxazole, the publication is Monatsschrift fuer Brauwissenschaft (1988), 41(9), 344-52, database is CAplus.

The N-containing heterocyclic compounds in malt and beer were extracted and determined by gas chromatog. They were analyzed at a sniffing port as they came off the gas chromatograph, and the aroma of many of the substances was described.

Monatsschrift fuer Brauwissenschaft published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C5H7NO, Application of 4,5-Dimethyloxazole.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Belaidi, Salah published the artcileElectronic structure and physical-chemistry property relationship for oxazole derivatives by ab initio and DFT methods, Category: oxazolidine, the publication is Organic Chemistry International (2011), 254064, 7 pp., database is CAplus.

The geometric, electronic structure, effect of the substitution, and structure phys.-chem. relationship for oxazoles derivatives have been studied by ab initio and DFT theory. In the present work, the calculated values, namely, net charges, bond lengths, dipole moments, electron affinities, heats of formation, and QSPR properties are reported and discussed in terms of the reactivity of oxazole derivatives

Organic Chemistry International published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C5H7NO, Category: oxazolidine.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Kondrat’eva, G. Ya. published the artcileReaction of oxazoles with dienophiles of methylenemalonic ester type, Safety of 4,5-Dimethyloxazole, the publication is Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya (1972), 2125-6, database is CAplus.

Oxazoles (I) reacted with dienophiles e.g. CH:C-(CO2Et)2 (II) by 1,4-cycloaddition to give 25-40 adduct (III, R1 = PrO, BuO, Me; R2 = H, Me; R3 = CO2Et, Ac). All the dienophiles tried reacted with I (R1 = alkoxy), but I (R1 = Me) reacted with II only. I (R = PrO) and piperidinylcyclo-pentene reacted similarly to give 26 1:1 adduct. II were stable in storage or when heated to 200°.

Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C5H7NO, Safety of 4,5-Dimethyloxazole.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Belaidi, Salah published the artcileElectronic structure and effect of methyl substitution in oxazole and thiazole by quantum chemical calculations, Related Products of oxazolidine, the publication is Research Journal of Pharmaceutical, Biological and Chemical Sciences (2014), 5(3), 811-818, database is CAplus.

Geometric and electronic structure of oxazole and thiazole and the effect of Me group substitution in thiazole and oxazole have been studied by PM3, ab initio method and d. functional Theory. In the present work, the calculated values, namely net charges, bond length, dipole moments, ionization potentials, electron-affinities and heats of formation are reported and discussed in terms of the reactivity of oxazole and thiazole systems.

Research Journal of Pharmaceutical, Biological and Chemical Sciences published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C5H7NO, Related Products of oxazolidine.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Nishimura, O. published the artcileIdentification of volatile flavor components of the oil from roasted sesame seeds, Application of 4,5-Dimethyloxazole, the publication is Koryo (1990), 91-101, database is CAplus.

Two hundred and twenty-one constituents were identified from the volatile extract obtained by steam distillation of the oil from roasted sesame seeds. One hundred and forty-six of these compounds are reported for the first time in the aroma of roasted sesame seed, 7 of which were newly identified as naturally occurring flavor components. Two dithioketones, 1-methyl-2-propanone and 1-methyldithio-2-butanone, are new compounds

Koryo published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C5H7NO, Application of 4,5-Dimethyloxazole.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Medvedskaya, L. B. published the artcileStructural orientation of heterodiene synthesis during the reaction of oxazoles with acetylenic dienophiles, Name: 4,5-Dimethyloxazole, the publication is Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya (1973), 1311-15, database is CAplus.

The Hueckel approximation of MO calculation gave the energy level values and electron densities in oxazoles with H, Me, Ac, CO2R and OR in the 5-position and Me in the 4-position. The stabilization energies of probable transition states in reactions of these compounds with acetylenic dienophiles (Et propiolate or Et phenylpropiolate) were computed. The results of these calculations agreed with the general results of Diels-Alder reactions of these substances. The π-electron density in the reactants was not a satisfactory criterion for deducing the orientation of such reactions since dynamic features were important. Hence, stabilization energy or some index of reactivity that describes reactant polarizability was the more useful parameter.

Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C5H7NO, Name: 4,5-Dimethyloxazole.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Sanz, Cristina published the artcileProfiles of volatile compounds and sensory analysis of three blends of coffee: influence of different proportions of Arabica and Robusta and influence of roasting coffee with sugar, SDS of cas: 20662-83-3, the publication is Journal of the Science of Food and Agriculture (2002), 82(8), 840-847, database is CAplus.

One hundred and forty-six volatile compounds were identified and quantified using a static headspace sampler in 3 blends of coffee: Arabica/Robusta 80:20 (A80:R20) natural roasted coffee, Arabica/Robusta 20:80 (A20:R80) natural roasted coffee and Arabica/Robusta 20:80 with 50% of Robusta coffee roasted with sugar (A20:R80 50% Torrefacto). The different proportion of Arabica and Robusta coffee in the blend A80:R20 vs. A20:R80 influenced the amounts of 20 chem. families of volatile compounds Aldehydes, ketones, alcs., pyrroles, pyrazines, furans, thiazoles, thiophenes, esters, oxazoles, lactones, sulfur compounds, pyridines, alkanes, alkenes, phenolic compounds, benzenic compounds, acids, pyranones and terpenes were present in higher quantities in the sample containing 80% of Arabica coffee, whereas sulfur compounds were more abundant in the coffee with 80% of Robusta. Sensory differences were also found between the 2 blends of coffee in the burnt, caramel, nutty, earthy and roasty notes. Torrefacto coffee, widely consumed in Spain, is obtained by roasting coffee with sugar. Higher quantities of ketones, alcs., pyrazines, furans, pyridines, alkanes, phenolic compounds, pyranones and terpenes were found in the blend A20:R80 50% Torrefacto coffee vs. A20:R80 natural roasted coffee. These differences in the volatile fraction were perceived by our panelists in the intensities of the nutty, roasty, earthy, burnt and caramel notes.

Journal of the Science of Food and Agriculture published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C5H7NO, SDS of cas: 20662-83-3.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Hoff, Signe published the artcileQuality of pilsner malt and roasted malt during storage, Recommanded Product: 4,5-Dimethyloxazole, the publication is Journal of the Institute of Brewing (2014), 120(4), 331-340, database is CAplus.

Malt is usually expected to be stable during 12 mo of storage. However, in practice many brewers notice changes in malt aroma during storage. The oxidative stabilities of pilsner malt and roasted malt were evaluated during a 12 mo storage at different temperatures (10 and 20 °C) and water activities (0.231 and 0.432). The radical content in malt kernels was measured by ESR spectroscopy and the volatile profile of the resulting sweet worts was measured by head-space anal. followed by GC-MS anal. The storage of malt resulted in oxidative reactions and a large change of the volatile profile of the resulting worts. Roasted malt was much more unstable than pilsner malt, as illustrated by a higher initial radical intensity, larger radical decay during storage and a larger change in the volatile profile of the wort with increased amounts of lipid oxidation products. For both roasted malt and pilsner malt, good correlations were found between radical decay and changes in the volatile profile of the wort, where high temperature and high water activity resulted in the largest changes. During the 12 mo of storage, the sugar extract of the wort made from the malts remained constant and was not affected by the chem. changes. This study suggests that chem. changes occurring in malts during less than 12 mo of storage may potentially affect the aroma of beer, and that water activity and storage temperature should both be kept low in order to maintain a high malt quality. Copyright © 2014 The Institute of Brewing & Distilling

Journal of the Institute of Brewing published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C5H7NO, Recommanded Product: 4,5-Dimethyloxazole.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Terent’ev, P. B. published the artcileReaction of vinylpyridines with oxazoles, COA of Formula: C5H7NO, the publication is Khimiya Geterotsiklicheskikh Soedinenii (1980), 1255-62, database is CAplus.

The regioselectivity observed in the cycloaddition reactions of vinylpyridines with oxazoles was predicted by MO calculation of HOMO and LUMO energies and product stabilization energies. Thus, 2-vinylpyridine reacted with 2,4-dimethyloxazole (I) to give II; III reacted with I to give IV. The structure of the bicyclic products was determined by oxidation to bipyridines and spectral anal. of the latter.

Khimiya Geterotsiklicheskikh Soedinenii published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C11H24O3, COA of Formula: C5H7NO.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Zhou, Zhilei published the artcileElucidation of the aroma compositions of Zhenjiang aromatic vinegar using comprehensive two dimensional gas chromatography coupled to time-of-flight mass spectrometry and gas chromatography-olfactometry, Computed Properties of 20662-83-3, the publication is Journal of Chromatography A (2017), 218-226, database is CAplus and MEDLINE.

In this work, a method to characterize the aroma compounds of Zhenjiang aromatic vinegar (ZAV) was developed using comprehensive two dimensional gas chromatog. (GC × GC) coupled with time-of-flight mass spectrometry (TOFMS) and gas chromatog. olfactometry (GC-O). The column combination was optimized and good separation was achieved. Structured chromatograms of furans and pyrazines were obtained and discussed. A total of 360 compounds were tentatively identified based on mass spectrum match factors, structured chromatogram and linear retention indexes comparison. The most abundant class in number was ketones. A large number of esters, furans and derivatives, aldehydes and alcs. were also detected. The odor-active components were identified by comparison of the reported odor of the identified compounds with the odor of corresponding GC-O region. The odorants of methanethiol, 2-methyl-propanal, 2-methyl-butanal/3-methyl-butanal, octanal, 1-octen-3-one, di-Me trisulfide, trimethyl-pyrazine, acetic acid, 3-(methylthio)-propanal, furfural, benzeneacetaldehyde, 3-methyl-butanoic acid/2-methyl-butanoic acid and phenethyl acetate were suspected to be the most potent. About half of them were identified as significant aroma constituents in ZAV for the first time. Their contribution to specific sensory attribute of ZAJ was also studied. The results indicated that the presented method is suitable for characterization of ZAV aroma constituents. This study also enriches our knowledge on the components and aroma of ZAV.

Journal of Chromatography A published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C6H6N2O, Computed Properties of 20662-83-3.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem