Tag: M.W=100-150

Sanchez, Carlos published the artcileProfiling of Organic Compounds in Bioethanol Samples of Different Nature and the Related Fractions, Application In Synthesis of 14667-55-1, the main research area is bioethanol VOC gas chromatog mass spectrometry flame ionization detection.

Forty-one bioethanol real samples and related fractions, together with a biobutanol sample, have been analyzed with gas chromatog. coupled to either mass spectrometry (GC-MS) or flame ionization detection (GC-FID). Bioethanol with different water contents, samples originated from several sources of biomass, first- as well as second-generation specimens, distillation fractions, samples stocked in containers made of four different materials, and, finally, a biobutanol sample have been analyzed. The number of the compounds found through GC-MS has been 130, including alcs., aldehydes, ketones, esters, ethers, nitrogen compounds, organic acids, furane derivates as well as other species (e.g., limonene). Afterward, a quant. determination of major components of bioethanol has been carried out. The achieved results have revealed that, besides ethanol and, in some cases, water, species such as acetaldehyde, methanol, and higher alcs., as well as 1,1-diethoxyethane, may be present at concentrations above 500 mg L-1. While the source of bioethanol (nature of the raw material, ethanol generation, or water content) has a direct impact on its volatile organic compound (VOC) profile, the material of the container where the biofuel has been stored does not play a significant role. Finally, the results have demonstrated that, for a given production process, different distillation fractions contain unequal VOC profiles.

ACS Omega published new progress about Alcohols Role: OCU (Occurrence, Unclassified), OCCU (Occurrence). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Application In Synthesis of 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Saha, Bittu published the artcileOrgano-Cu (II) catalyst: an efficient synthesis of substituted n-heterocycles via double condensation/ tandem oxidation-cyclization/elimination-cyclization reactions from easily accessible precursors, Name: 2,3,5-Trimethylpyrazine, the main research area is organo copper catalyst preparation; diketone diamine copper catalyst tandem cyclization; pyrazine preparation; carbonyl compound phenylene diamine copper catalyst tandem cyclization; quinoxaline preparation.

Several efficient, robust, versatile and straightforward strategies for the diversity-oriented convergent synthesis of a vast range of highly functionalized biol. active N-heterocycles such as quinoxaline, pyrazine, cyanopyrazine derivatives from different easily accessible, inexpensive starting motif has been reported by exploring the promising organo Cu (II) catalyst via double condensation/ tandem oxidation-cyclization/elimination-cyclization reactions. These methodologies have several advantages such as inexpensive, non-toxic starting materials as well as catalyst and easy reaction set-up. Avoid the use of hazardous materials has added another important advantage in these protocols.

Rasayan Journal of Chemistry published new progress about Acid bromides Role: RCT (Reactant), RACT (Reactant or Reagent). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Name: 2,3,5-Trimethylpyrazine.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Calva-Estrada, S. J. published the artcileThermal properties and volatile compounds profile of commercial dark-chocolates from different genotypes of cocoa beans (Theobroma cacao L.) from Latin America, Recommanded Product: 2,3,5-Trimethylpyrazine, the main research area is Theobroma cacao thermal property volatile compound dark chocolate genotype; 2,3-Butanediol (PubChem CID 262); 2-Methylpropanoic acid (PubChem CID 6590); 2-Nonanone (PubChem CID 13187); 2-Phenylethyl acetate (PubChem CID 7654); 2-Phenylethyl alcohol (PubChem CID 6054); 3-Methyl-butanal (PubChem CID 11552); Benzaldehyde (PubChem CID 240); Chemometrics; Differential scanning calorimetry; Furfural (PubChem CID 7362); Hierarchical cluster analysis heatmap; Polymorphism; Principal component analysis; Tetramethylpyrazine (PubChem CID 14296); Trimethylpyrazine (PubChem CID 26808).

There is a growing interest in the identification of chemometric markers that allow the distinction and authentication of dark-chocolates according to their cocoa geog. origin and/or genotype. However, samples derived from Latin American cocoa, including specimens from North and South America, have not been studied in this context. An exploration of the melting behavior, fat composition, bioactive content, and volatile profile of com. darkchocolates was conducted to identify possible patterns related to the genotype and/or origin of cocoa from Latin America. The melting properties were evaluated by DSC and related to fat content and fatty acids profile. Total polyphenol, anthocyanin, methylxanthine, and catechin content were analyzed. Finally, the volatile compounds were extracted and identified by HS-SPME/GC-MS and were analyzed through Principal Component Anal. (PCA) and the Hierarchical Cluster Anal. Heatmap (HCA Heatmap). The fatty acids profile showed a relationship with the melting properties of dark chocolate. The samples exhibited two glass-transition temperatures (Tg) at 19°C and 25.5°C, possibly related to traces of unstable polymorphic forms of monounsaturated triacylglycerides. The anal. of bioactive compounds demonstrated great variability among samples independent of the cocoa origin, genotype, and content. The PCA and HCA Heatmaps allowed discriminating against the chocolates in relation to the cocoa origin and genotype. Compounds like tetramethylpyrazine, trimethylpyrazine, benzaldehyde, and furfural could be considered as dark-chocolate aroma markers derived from Latin American cocoas (North American region). The 2-phenylethyl alc., 2-methylpropanoic acid, 2,3-butanediol, 2-nonanone, and limonene for derived from South America. And the 2-phenylethyl acetate, 3-methyl-butanal, and cinnamaldehyde could allow to distinguishing between regional genotypes.

Food Research International published new progress about Anthocyanins Role: ANT (Analyte), ANST (Analytical Study). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Recommanded Product: 2,3,5-Trimethylpyrazine.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Zhao, Hong published the artcileVisible Light-Promoted Aliphatic C-H Arylation Using Selectfluor as a Hydrogen Atom Transfer Reagent, Recommanded Product: 2,3,5-Trimethylpyrazine, the main research area is alkane heteroarene selectfluor hydrogen atom transfer light arylation; heteroaryl alkyl derivative preparation.

A mild, practical method for direct arylation of unactivated C(sp3)-H bonds with heteroarenes has been achieved via photochem. Selectfluor is used as a hydrogen atom transfer reagent under visible light irradiation A diverse range of chem. feedstocks, such as alkanes, ketones, esters, and ethers, and complex mols. readily undergo intermol. C(sp3)-C(sp2) bond formation. Moreover, a broad array of heteroarenes, including pharmaceutically useful scaffolds, can be alkylated effectively by the protocol presented here.

Organic Letters published new progress about Alkanes Role: RCT (Reactant), RACT (Reactant or Reagent). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Recommanded Product: 2,3,5-Trimethylpyrazine.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Farag, Mohamed A. published the artcileRevealing compositional attributes of Glossostemon bruguieri Desf. root geographic origin and roasting impact via chemometric modeling of SPME-GC-MS and NMR metabolite profiles, Recommanded Product: 2,3,5-Trimethylpyrazine, the main research area is Glossostemon bruguieri root composition metabolite roasting chemometrics SPMEGCMS NMR.

Glossostemon bruguieri Desf. (Moghat, Sterculiaceae), is a shrub well-known for its thick long-tapering dark colored roots, grown in the Middle East and North Africa. Studies on Glossostemon have focused on its nutritive value and health benefits attributed to its phenolic content with no extensive anal. of secondary metabolome. NMR metabolite fingerprinting of 12 G. bruguieri root specimens of different origins using 1D and 2D experiments identified 12 major primary and secondary metabolites. Orthogonal partial least squares-discriminant anal. (OPLS-DA) of NMR aromatic regions was competent in discriminating between roots origin based on moghatin and pinoresinol levels. Quantification of 1H NMR spectra revealed enrichment of Siwa specimens in sugars i.e., sucrose and inositol (17.89 and 12.06μg/mg, resp.), as well as some secondary metabolites viz. moghatin, pinoresinol, takakin and fraxetin (7.73, 4.55, 3.81 and 3.03μg/mg, resp.), posing it for future incorporation in nutraceuticals. However, much less is known regarding aroma and roasting impact on root chem. composition Volatile profiles of 15 unroasted and roasted specimens were analyzed using headspace solid-phase microextraction coupled to mass spectrometry. 100 Volatile constituents were identified dominated by aldehydes, ethers and mono- and sesquiterpenes, whereas esters were abundant in roasted roots. OPLS-DA identified 2-ethyl-6-methylpyrazine and 5-methyl-2-furfural as roasting descriptors.

Journal of Food Composition and Analysis published new progress about Aldehydes Role: ANT (Analyte), ANST (Analytical Study). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Recommanded Product: 2,3,5-Trimethylpyrazine.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Szambelan, Katarzyna published the artcileLow-waste technology for the production of bioethanol from sorghum grain: Comparison of Zymomonas mobilis and Saccharomyces cerevisiae in fermentation with stillage reusing, Quality Control of 14667-55-1, the main research area is Zymomonas Saccharomyces fermentation stillage bioethanol low waste technol.

Zymomonas mobilis and Saccharomyces cerevisiae have been used for simultaneous saccharification and fermentation of sorghum grain with the reuse of the stillage. This study investigated the effects of replacing half the water by a stillage liquid fraction on ethanol yield and volatile compound synthesis. Studies have shown that Z. mobilis is more efficient in ethanol production (55.96-61.48 g/L) than S. cerevisiae (55.26-58.38 g/L). Addnl., Z. mobilis had the advantage of a shorter fermentation time (48 h) and lower fermentation temperature (35°C) than distillery yeast. No relationship was observed between successive stillage reusing and ethanol content. Reusing the liquid fraction of the stillage did not increase the amount of volatile compounds identified in the raw distillates. Significant differences were observed in the volatile compounds profile of bacterial and yeast raw distillates. Acetaldehyde was the dominant compound in bacterial raw distillates, whereas 3-methylbutan-1-ol was the dominant compound in yeast raw distillates. The characteristic of Z. mobilis was the production of fewer (4.31-6.03 g/L spirit 100%) volatile compounds compared to yeast (4.04-7.44 g/L spirit 100%). The fermentation process reusing the liquid part of the stillage made it possible to reduce process water consumption and waste generation in bioethanol production from sorghum grain. In addition, Z. mobilis made ethanol production from sorghum grain grown in Eastern Europe more beneficial.

Journal of Cleaner Production published new progress about Alcohols Role: ANT (Analyte), ANST (Analytical Study). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Quality Control of 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Marseglia, Angela published the artcileVolatile fingerprint of unroasted and roasted cocoa beans (Theobroma cacao L.) from different geographical origins, Synthetic Route of 14667-55-1, the main research area is cocoa bean authenticity volatile geol HSSPME GC MS; Authenticity; Fermented cocoa beans; Fingerprint; Geographical origin; Roasted cocoa beans; Volatilome.

The aroma characterization of 58 unroasted cocoa beans from 22 different geog. origins was performed by head space solid phase micro-extraction (HS-SPME) combined with gas chromatog.-mass spectrometry (GC-MS). Sampling is representative of the average world production (America, Africa, and Southeast Asia). Anal. of cocoa beans before and after roasting were performed to follow the aroma modification with the aim to achieve a cocoa volatile fingerprint and a discrimination model based on beans origin. A total of 57 volatiles was identified in unroasted cocoa beans, while 71 volatiles were identified in roasted cocoa beans. The compounds belong to several chem. groups including esters, alcs., organic acids, aldehydes, ketones and pyrazines. Datasets were submitted to multivariate statistical anal. (Principal Component Anal., PCA). Results allowed to discriminate unroasted cocoa beans based on their geog. origin: samples coming from African countries were separated from samples of American regions, whereas samples from Southeast Asia lie between the other two continents suggesting that Asian samples have intermediate characteristics between African and South American cocoa beans. PCA, applied on the corresponding roasted samples, showed that although the same roasting treatment has been applied to all the samples, the differences among the unroasted samples were also maintained in the aromatic profile after roasting. The discrimination model based on volatile fingerprint combined with chemometric tools, showed interesting potential for origin authentication of both unroasted and roasted cocoa beans.

Food Research International published new progress about Alcohols Role: ANT (Analyte), ANST (Analytical Study). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Synthetic Route of 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Zhou, Qi published the artcileCharacterization of the Aroma-Active Compounds in Commercial Fragrant Rapeseed Oils via Monolithic Material Sorptive Extraction, Quality Control of 14667-55-1, the main research area is aroma rapeseed oil monolithic material sorptive extraction GC MS; OAV; aroma-active compounds; commercial fragrant rapeseed oils; monolithic material sorptive extraction.

Com. fragrant rapeseed oil (CFRO), from roasted and hot-pressed seed, is enjoyed in China for its unique aroma. However, the characteristic of aroma-active compounds in CFRO is still unclear. In this study, a new odor monolithic material sorptive extraction method was established to trap volatiles from rapeseed oil. Thirty CFROs were investigated using this method coupled with gas chromatog.-mass spectrometry(GC-MS). A total of 29 volatile compounds were identified by gas chromatog.-olfactometry(GC-O) including pyrazines, alcs., aldehydes, ketones, and sulfur compounds,. Further, 2,5-dimethylpyrazine(peanut-like), 3-ethyl-2,5-dimethylpyrazine(roasted nut-like), di-Me trisulfide(cabbage-like), 4-isothiocyanato-1-butene(pungent and pickle-like), butyrolactone(caramel-like), and benzyl nitrile(pungent and sulfur-like) are affirmed as the key odorants for the overall aroma of CFRO, owing to their odor activity values≥1. This work provides a new insight on acquiring aroma-active compounds from rapeseed oil in a more time-effective process compared to conventional methods. This novel approach is applicable in the field of food flavor in the further.

Journal of Agricultural and Food Chemistry published new progress about Alcohols Role: ANT (Analyte), ANST (Analytical Study). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Quality Control of 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Thi Le, Dung Huynh published the artcileBioactive and Physicochemical Characteristics of Natural Food: Palmyra Palm (Borassus flabellifer Linn.) Syrup, Name: 2,3,5-Trimethylpyrazine, the main research area is bioactive physicochem characteristic natural food palmyra palm; Borassus flabellifer L.; in vitro antioxidant activity; palmyra palm syrup; physicochemical characteristics; ultrafiltration; volatile compounds.

Palmyra palm syrup, produced from Borassus flabellifer flowers sap, is rich in nutrients and minerals and has unique flavors. This study evaluated the in vitro antioxidant activity, physicochem. characteristics, and Maillard reaction products of palmyra palm syrup prepared by thermal and ultrafiltration processes. Palmyra palm syrup prepared by a thermal process had smaller L*, b* values, and larger a* values than that prepared by an ultrafiltration process. Palmyra palm syrup contained 10 vitamins, the most abundant being vitamin E. Overall, 38 volatile compounds were found and classified into six groups in the order of alcs. > acids > ketones > sulfurs > pyrazines> phenols and aldehyde. Volatile compounds depended on concentration, temperature, and ultrafiltration process. Protein content decreased because of participation in the Maillard reaction and increased 5-hydroxymethylfurfural (HMF) and total phenolic content. The HMF content was very low (0.02-14.95 mg/100 g). The radical scavenging activity of 2,2-diphenyl-1-1 picrylhydrazyl and 2,20-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) in palmyra palm syrup with thermal process was higher than with ultrafiltration. This study established that ultrafiltration pretreatment of palmyra palm syrup generated a good appearance and reduced the HMF content, however, it neg. affected the volatile compounds and physicochem. characteristics.

Biology (Basel, Switzerland) published new progress about Acids Role: ANT (Analyte), ANST (Analytical Study). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Name: 2,3,5-Trimethylpyrazine.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Kim, Dahye published the artcileThe effect of roasting on capsaicinoids, volatile compounds, and fatty acids in Capsicum annuum L. (red pepper) seeds, Product Details of C7H10N2, the main research area is Capsicum seed capsaicinoids volatile compound fatty acids roasting; Capsaicinoids; Capsicum annum L. (red pepper) seeds; Change; Fatty acids; Roasting; Volatile compounds.

Capsaicinoids, volatile compounds, and fatty acids were analyzed in red pepper seeds to determine any changes at different roasting temperatures The contents of capsaicin and dihydrocapsaicin decreased as roasting temperatures increased. 3-Ethyl-2,5-dimethylpyrazine, 2,3,5,6-tetramethylpyrazine, 2-methoxy-3-(2-methylpropyl)pyrazine, 1-methylpyrrole, hexanedial, benzeneacetaldehyde, 2-acetylfuran, and butane-2,3-diol were newly detected in red pepper seeds roasted at 100°C. Concentrations of pyrazines, pyrroles, oxygen-containing heterocyclic compounds, carbonyls, and alcs. increased rapidly in red pepper seeds as the roasting temperature increased. Such compounds could contribute roasted, grilled, and sweet odor notes to roasted red pepper seeds. Linoleic acid was the predominant fatty acid in all red pepper seeds. There were no significant differences in polyunsaturated fatty acids in red pepper seeds as roasting temperature increased. In conclusion, roasting red pepper seeds could be used in thermally processed foods because during roasting their pungency is reduced, desirable savory odors are enhanced, and the levels of polyunsaturated fatty acids remain unchanged.

Food Science and Biotechnology published new progress about Alcohols Role: BSU (Biological Study, Unclassified), BIOL (Biological Study). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Product Details of C7H10N2.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem