Month: November 2022

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

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

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

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

Kwak, Se Hun published the artcileSynthesis of N-substituted 2-aminothiazolo[4,5-b]pyrazines by tandem reaction of o-aminohalopyrazines with isothiocyanates, Formula: C4H2Br2ClN3, the main research area is pyrazine thiazole preparation tandem reaction; chloro pyrazinamine cyclization isothiocyanate; bromo aminopyrazine cyclization isothiocyanate.

Under optimized reaction conditions, the synthesis of the target compounds was achieved by a sodium hydroxide-mediated tandem reaction of isothiocyanate derivatives with 3-halo-2-pyrazinamine. A reaction of isothiocyanate derivatives with 3-chloro-2-pyrazinamine derivatives gave N-(phenyl)thiazolo[4,5-b]pyrazin-2-amine (I) and related substances.

Bulletin of the Korean Chemical Society published new progress about Azoles Role: SPN (Synthetic Preparation), PREP (Preparation). 566205-01-4 belongs to class pyrazines, name is 2-Amino-3,5-dibromo-6-chloropyrazine, and the molecular formula is C4H2Br2ClN3, Formula: C4H2Br2ClN3.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Meti, Puttavva published the artcileSynthesis, characterization and optoelectronic properties of pyrrolopyrazine based Y-shaped color-tunable dipolar molecules, Category: pyrazines, the main research area is color tunable pyrrolopyrazine preparation thermal optoelectronic fluorescence.

A regioselective approach for the synthesis of functionalized dipolar Y-shaped chromophores is demonstrated. A series of dipolar pyrrolopyrazine based mols. were prepared in a straightforward manner. The key step in the preparation of the chromophores involves two-fold Sonogashira coupling reaction between the pyrrolopyrazine core and acetylene derivatives Different electron-donors, including, NH2, NMe2, OMe and CF3, CN acceptors were incorporated into the chromophores. By adjusting the substituents at 2, 3, and 6-position of the pyrrolopyrazine, dipolar tunable mols. with wide emission band are synthesized. The optical, thermal, and electrochem. properties of the materials are analyzed and the results are supported with the DFT calculations The preliminary studies of these engineered Y-shaped mols. indicate their potential as new building blocks in the fields of optoelectronic devices.

Dyes and Pigments published new progress about Alkynes, α- Role: RCT (Reactant), RACT (Reactant or Reagent). 566205-01-4 belongs to class pyrazines, name is 2-Amino-3,5-dibromo-6-chloropyrazine, and the molecular formula is C4H2Br2ClN3, Category: pyrazines.

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

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

Nishiyama, Yoshitake published the artcileFacile Synthesis of Tetraarylpyrazines by Sequential Cross-coupling Approach, Application In Synthesis of 566205-01-4, the main research area is tetraarylpyrazine preparation; triarylpyrazine arylboronic acid cross coupling.

A facile synthetic method for unsym. tetraarylpyrazines I (R = 4-CH3C6H4, 2-naphthyl; R1 = 4-CF3C6H4, 4-(OTBS)C6H4, 4-NCC6H4; R2 = C6H5, 4-CH3OC6H4; R3 = 4-FC6H4, 4-N(CH3)2C6H4, 2-OHC6H4, 4-F3CC6H4, 4-N(C6H5)2C6H4) by sequential cross-couplings is disclosed. This 5-step synthesis was achieved from 2-amino-3,5-dibromo-6-chloropyrazine through four-fold cross-coupling and diazotization. Dibenzo-fused quinoxaline like 2-(4-methoxyphenyl)-7-methyl-3-(4-(trifluoromethyl)phenyl)dibenzo[f,h]quinoxaline synthesis was also accomplished by further intramol. coupling.

Chemistry Letters published new progress about Arylboronic acids Role: RCT (Reactant), RACT (Reactant or Reagent). 566205-01-4 belongs to class pyrazines, name is 2-Amino-3,5-dibromo-6-chloropyrazine, and the molecular formula is C4H2Br2ClN3, Application In Synthesis of 566205-01-4.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Ma, Zhuang published the artcileStable and reusable Ni-based nanoparticles for general and selective hydrogenation of nitriles to amines, Product Details of C5H8ClN3, the main research area is aryl nitrile nickel nanocatalyst selective hydrogenation; aromatic primary amine preparation; recyclable silica support nickel catalyst preparation.

Silica supported ultrasmall Ni-nanoparticles allow for general and selective hydrogenation of all kinds of nitriles to primary amines under mild conditions. By calcination of a template material generated from Ni(II)nitrate and colloidal silica under air and subsequent reduction in the presence of mol. hydrogen the optimal catalyst was prepared The prepared supported nanoparticles are stable, was conveniently used and easily recycled. The applicability of the optimal catalyst material was shown by hydrogenation of >110 diverse aliphatic and aromatic nitriles including functionalized and industrially relevant substrates. Challenging heterocyclic nitriles, specifically cyanopyridines, provided the corresponding primary amines in good to excellent yields. The resulting amines serve as important precursors and intermediates for the preparation of numerous life science products and polymers.

Chemical Science published new progress about Aliphatic nitriles Role: RCT (Reactant), RACT (Reactant or Reagent). 39204-49-4 belongs to class pyrazines, name is Pyrazin-2-ylmethanamine hydrochloride, and the molecular formula is C5H8ClN3, Product Details of C5H8ClN3.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem