Category: Pyrazines

Thompson, Andrew M. published the artcileHeteroaryl ether analogues of an antileishmanial 7-substituted 2-nitroimidazooxazine lead afford attenuated hERG risk: In vitro and in vivo appraisal, COA of Formula: C5H2ClF3N2, the main research area is nitroimidazo oxazine heteroaryl ether analog preparation antileishmanial; Chagas disease; Leishmaniasis; Pharmacokinetics; Pretomanid; hERG inhibition; in vivo efficacy.

Previous investigation of the potent antileishmanial properties of antitubercular 7-substituted 2-nitroimidazo[2,1-b][1,3]oxazines with biaryl side chains led to our development of a new clin. candidate for visceral leishmaniasis (DNDI-0690). Within a collaborative backup program, a racemic monoaryl lead (3) possessing comparable activity in mice but a greater hERG liability formed the starting point for our pursuit of efficacious second generation analogs having good solubility and safety. Asym. synthesis and appraisal of its enantiomers first established that chiral preferences for in vivo efficacy were species dependent and that neither form afforded a reduced hERG risk. However, in line with our findings in a structurally related series, less lipophilic heteroaryl ethers provided significant solubility enhancements (up to 16-fold) and concomitantly attenuated hERG inhibition. One promising pyridine derivative (49) displayed 100% oral bioavailability in mice and delivered a 96% parasite burden reduction when dosed at 50 mg/kg in a Leishmania donovani mouse model of visceral leishmaniasis.

European Journal of Medicinal Chemistry published new progress about Drug bioavailability. 799557-87-2 belongs to class pyrazines, name is 2-Chloro-5-(trifluoromethyl)pyrazine, and the molecular formula is C5H2ClF3N2, COA of Formula: C5H2ClF3N2.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Jin, Feng published the artcileRoasted tree peony (Paeonia ostii) seed oil: Benzoic acid levels and physicochemical characteristics, Synthetic Route of 14667-55-1, the main research area is Paeonia seed oil benzoic acid phenol hexanal roasting.

Tree peony seeds oil (TPSO, Paeonia ostii) extracted at different roasting temperatures were studied for color, acid values, total phenols, fatty acid composition, antioxidant capacity, volatiles, and benzoic acid. Roasting led to increased antioxidant capacity and acid values. Headspace anal. of raw peony seed oil showed only six volatile compounds, while after roasting volatiles such as pyrazines, aldehydes and furans were observed and contributed to nutty aromas. Unsaturated fatty acids constituted more than 90% of the total fatty acids with α-linolenic acid as the predominant fatty acid of TPSO and was not significantly changed with roasting temperature Benzoic acid concentration increased significantly as roasting temperature increased. Although the occurrence of benzoic acid in virgin oil might be a concern, it can be removed through refining for com. production

International Journal of Food Properties published new progress about Natural antioxidants. 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

Liu, Ping published the artcileEffects of Different Fermentation Strains on the Flavor Characteristics of Fermented Soybean Curd, Name: 2,3,5-Trimethylpyrazine, the main research area is Actinomucor Rhizopus Mucor fermented soybean curd flavor; E-nose; HS-SPME-GC-MS; fermentation strains; fermented soybean curd; sensory evaluation.

The effects of different fermentation strains on the flavor characteristics of fermented soybean curd (FSC) were investigated in this study. Fresh tofu was fermented by Actinomucor elegans, Rhizopus arrhizus, Mucor racemosus, and Rhizopus chinensis, either alone or in various combinations. The FSC manufacturing process included prefermentation by different strains at 28 °C for 60 h, followed by salting at 16 °C for 7 days and finally proceeding postfermentation at 25 °C for 35 days. Subsequently, five tested samples were obtained, namely, sample A (fermented by A. elegans alone), R (fermented by R. arrhizus alone), AR (fermented by A. elegans and R. arrhizus at 5:1), AM (fermented by A. elegans and M. racemosus at 1:1), and RR (fermented by R. arrhizus and R. chinensis at 7:3). The flavors of the five samples were determined by E-nose, sensory evaluation, and GC-MS. E-nose system observed significant discriminations by principal component anal. and linear discriminant anal. anal. Sensory evaluation ranked the overall sensory scores: AR>AM>A>RR>R. As shown in GC-MS results, sample AR also had, on average, the highest level of many volatiles. Out of 10 critical volatiles, the detected frequency of samples AR, AM, RR, A, and R was 10, 9, 9, 8, and 7, resp. PLS2 regression model was used to explore the influence on flavor quality of different strains. All three analytic methods revealed similar results, with sample AR providing the best flavor quality, while the opposite was the case with sample R. Therefore, it could be concluded that A. elegans and R. arrhizus at 5:1 (volume/volume) was the optimal combination, and may likely promote the production of critical volatile compounds Practical Application : The flavors of fermented soybean curds are influenced by various factors such as physicochem. and microorganism during the fermentation surroundings. The results of this work not only provide valuable information for FSC flavor studies, but can also guide the FSC industry to improve flavor quality by applying the most appropriate production strains.

Journal of Food Science published new progress about Actinomucor elegans. 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

He, Guiqiang published the artcileAlteration of microbial community for improving flavor character of Daqu by inoculation with Bacillus velezensis and Bacillus subtilis, Quality Control of 14667-55-1, the main research area is Bacillus bioaugmentation Daqu flavor volatile compound.

Daqu, an important saccharification and fermentation starter, provides microbes, hydrolytic enzymes, and flavor compounds, and plays a crucial role for production of Chinese Baijiu. To evaluate the feasibility of bioaugmentation inoculated with Bacillus velezensis and Bacillus subtilis for improving the flavor character of Daqu, microbial community, enzyme activity, and volatile compound were analyzed and compared between traditional Daqu (T Daqu) and fortified Daqu (F Daqu). Bioaugmentation inoculation increased the abundance of Bacillus, Lactobacillus, and Candida. Addnl., anal. of enzyme activity showed that liquefying power, saccharifying power, and esterifying power were significantly higher (P < 0.05) in F Daqu than T Daqu. Meanwhile, the contents of volatile compounds including esters, pyrazines, and alcs. significantly increased (P < 0.05) after bioaugmentation inoculation. In particular, the contents of tetramethylpyrazine and phenethyl alc. in F Daqu significantly increased (P < 0.05) by 90.8% and 69.5% compared to T Daqu, resp. Moreover, many enzymes involved in saccharification, ethanol fermentation, and aroma generation were predicted, and the abundance of their encoding genes obviously increased in F Daqu. Taken as whole, bioaugmentation inoculation with B. velezensis and B. subtilis altered the microbial community for regulating their metabolic activities, and subsequently, improved the flavor character of Daqu. LWT--Food Science and Technology published new progress about Alcoholic beverages. 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

Mu, Xiaoqing published the artcileOptimization and Validation of a Headspace Solid-Phase Microextraction with Comprehensive Two-Dimensional Gas Chromatography Time-of-Flight Mass Spectrometric Detection for Quantification of Trace Aroma Compounds in Chinese Liquor (Baijiu), Product Details of C7H10N2, the main research area is Chinese liquortracein aroma compound solid phase microextraction; Chinese liquor (Baijiu); GC×GC-TOFMS; quantitative analysis; trace aroma compounds.

The detection of trace aroma compounds in samples with complex matrixes such as Chinese liquor (Baijiu) requires a combination of several methods, which makes the anal. process very complicated. Therefore, a headspace solid-phase microextraction (HS-SPME) method coupled with two-dimensional gas chromatog. time-of-flight mass spectrometry (GCxGC-TOFMS) was developed for the quantitation of a large number of trace compounds in Baijiu. Optimization of extraction conditions via a series of experiments revealed that dilution of the alc. content of 8 mL of Baijiu to 5%, followed by the addition of 3.0 g of NaCl and subsequent SPME extraction with DVB/CAR/PDMS fiber coating over 45 min at 45°C was the most suitable. To check the matrix effects, various model Baijiu matrixes were investigated in detail. The quant. method was established through an optimized model synthetic solution, which can identify 119 aroma compounds (esters, alcs., fatty acids, aldehydes and ketones, furans, pyrazines, sulfur compounds, phenols, terpenes, and lactones) in the Baijiu sample. The developed procedure provided high recovery (86.79-117.94%), good repeatability (relative standard deviation < 9.93%), high linearity (R2 > 0.99), and lower detection limits than reported methods. The method was successfully applied to study the composition of volatile compounds in different types of Baijiu. This research indicated that the optimized HS-SPME-GCxGC-TOFMS method was a valid and accurate procedure for the simultaneous determination of different types of trace compounds in Baijiu. This developed method will allow an improved anal. of other samples with complex matrixes.

Molecules published new progress about Alcoholic beverages. 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

Hinneh, Michael published the artcilePod storage with roasting: A tool to diversifying the flavor profiles of dark chocolates produced from ‘bulk’ cocoa beans? (part I: aroma profiling of chocolates), SDS of cas: 14667-55-1, the main research area is aroma flavor dark chocolate cocoa bean; Aroma profile; Chocolate; Cocoa; HS-SPME-GC–MS; Pod storage; Roasting.

The impact of pod storage (PS) and roasting temperature (RT) on the aroma profiles of dark chocolates were evaluated. Cocoa liquor samples comprised of ten different combinations of PS and RT, while keeping the roasting time fixed at 35 min. Addnl., com. cocoa liquors from renowned origins (Ecuador, Madagascar, Venezuela, Vietnam, Ivory Coast and Ghana) were acquired for comparison. From these, 70% dark chocolates were produced under the same conditions after which they were subjected to headspace solid-phase microextraction-gas chromatog.-mass spectrometry (HS-SPME-GC-MS) anal. Although both PS and RT were found to influence the aroma volatile concentrations, the impact of RT over PS seemed to be greater. An agglomerative hierarchical clustering (AHC) of all chocolates on the basis of their aroma profiles revealed a similar impact as earlier observed, where major clustering of the chocolates was in accordance with the intensity of the roasting process applied. However, within each group, the dissimilarities owing to PS among the chocolates was clearly depicted. Comparatively, chocolates with low (100-120 °C), instead of moderate to high (135-160 °C) RT’s, rather showed a low dissimilarity with those from the com. cocoa liquors of the different origins. Although from the same beans, the diversity of aroma profiles of these chocolates as well as the similitude of some treatments to some chocolates from com. grade cocoa liquors, unequivocally underscores the possibility for steering diverse distinct flavors from ‘bulk’ cocoa through PS and roasting, with beneficial implications, both from an application and an economic point of view.

Food Research International published new progress about Alcoholic beverages. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, SDS of cas: 14667-55-1.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Picard, Magali published the artcileDevelopment of a Solid-Phase Microextraction-Gas Chromatography/Mass Spectrometry Method for Quantifying Nitrogen-Heterocyclic Volatile Aroma Compounds: Application to Spirit and Wood Matrices, Formula: C7H10N2, the main research area is heterocyclic volatile aroma spirit wood solid microextraction GC MS; headspace solid-phase microextraction (HS-SPME); nitrogen-heterocyclic compounds; roasted-like aromas; spirit and oakwood matrices; wood aging bouquet.

Over wood aging, matured spirits developed a complex aromatic bouquet where roasted-like notes were often perceived. Since many nitrogen heterocycles were related to these olfactory nuances, a headspace solid-phase microextraction (HS-SPME) coupled to gas chromatog.-mass spectrometry was developed and validated to quantify them in both spirit and wood matrixes. The various parameters affecting the extraction of the analytes from both spirit and wood samples were first investigated (i.e., fiber coating phase, dilution, pH and volume sample, adding salt, extraction time and temperature, and incubation time) to determine the best compromise for a single-run anal. of the whole set of studied compounds Good linearity (R2 > 0.99), repeatability, reproducibility, accuracy and low detection, and quantification limits were obtained, making this anal. method a suitable tool for routine anal. of the selected nitrogen compounds Fifteen pyrazines, three pyrroles, and three quinolines were quantified in a series of oak wood and com. spirit samples where some of them were identified for the first time. The significant impact of some barrel features and the spirit in-wood maturation step on the N-heterocycle profile in both matrixes were finally discussed.

Journal of Agricultural and Food Chemistry published new progress about Alcoholic beverages. 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Formula: C7H10N2.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Birk, Florian published the artcileAroma active alkylated pyrazines are produced by Basfia succiniciproducens as by-products of succinic acid production, Synthetic Route of 14667-55-1, the main research area is Basfia succinic acid flavor dynamic headspace extraction.

Culture supernatants of Basfia succiniciproducens derived from the industrial production of succinic acid exhibit an intense nutty, root vegetable-like, buttery and sourish smell. By means of headspace-gas chromatog.-mass spectrometry-olfactometry (HS-GC-MS-O), 14 odor-active compounds were perceived and identified using two GC-columns of different polarity and comparison of retention indexes and mass spectra to those of authentic reference compounds Several alkylated pyrazines, including 2,3,5-trimethylpyrazine, 5-ethyl-2,3-dimethylpyrazine, 2,3,5,6-tetramethylpyrazine, 2,3,5-trimethyl-6-ethylpyrazine, 2,3,5-trimethyl-6-propylpyrazine and 2,3,5-trimethyl-6-butylpyrazine were found to contribute to the aroma of the culture supernatant. Quantitation of the pyrazines was performed by means of dynamic headspace-GC-MS after standard addition, and 2,3,5,6-tetramethylpyrazine (9.10 mg/L) was the most abundant compound Waste streams of the biotechnol. production of commodity chems. may thus represent a sustainable resource for the isolation of aroma compounds

Flavour and Fragrance Journal published new progress about Basfia succiniciproducens. 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

Pico, Joana published the artcileEffect of rice, pea, egg white and whey proteins on crust quality of rice flour-corn starch based gluten-free breads, Application In Synthesis of 14667-55-1, the main research area is gluten free bread crust rice pea egg white quality.

Gluten-free bread crusts are known for their crumbly texture, light color, poor nutritional quality and weak aroma. The objective of this research was to improve crust quality of gluten-free breads by the addition of rice, pea, egg white and whey proteins to the bread formulation in two levels (5% and 10%). Moisture, water activity, thickness, microstructure, texture, color and volatile compounds were measured. A 99% neg. significant correlation between spatial frequency of structural ruptures and crust moisture content was found. Results from texture anal. indicated that animal and 10% pea protein crusts were less crispy than control. Moreover, crust microstructure of animal protein bread was very different from control and vegetal protein crusts. Animal and vegetal protein crusts showed darker color than control and the darkest was obtained from whey protein inclusion. With respect to the volatile profiles, rice protein crusts had the highest content of 2-acetyl-1-pyrroline while whey protein crusts had high level of pyrazines, which was in concordance with their dark color. However, whey protein and, above all, rice protein also increased the content of volatile compounds from lipids oxidation Thus, the suitable proportion between rice and whey protein should be found to achieve the most pleasant aroma.

Journal of Cereal Science published new progress about Bread (gluten-free crust). 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

Boeswetter, Anke R. published the artcileIdentification of the Key Aroma Compounds in Gluten-Free Rice Bread, Application of 2,3,5-Trimethylpyrazine, the main research area is aroma compound rice bread; 2-aminoacetophenone; HRGC-QTOF-MS; flour aging; gluten-free; rice bread; wheat bread.

Rice flour is commonly used as a raw material in the preparation of gluten-free bread. However, compared to wheat bread, its aroma is different and often not accepted by consumers. Aroma profile analyses of the crumb and crust of freshly baked rice bread indicated a strong rice-like flavor but lower intensities of the typical roasty wheat bread odor qualities. By application of aroma extract dilution analyses (AEDA), the most odor active compounds in both rice and wheat bread samples were characterized. In addition, two batches of rice flour were used. In particular, 2-aminoacetophenone and 4-vinylphenol reached high flavor dilution (FD) factors in the rice bread samples but were not detected in wheat bread. In the rice bread crust 1-octene-3-one, (E)-2-nonenal, and 4-methylquinazoline reached significantly higher FD factors than in the wheat bread crust, while those of maltol and 2-methoxy-4-vinylphenol were significantly lower. In a stored rice flour and in the corresponding rice bread, lipid degradation products such as hexanal were more intense compared to fresh rice flour. Finally, five aroma-active compounds, namely, 2-butyl-2-heptenal, 2-propyl-2-octenal, 4-hydroxy-2-octenoic acid lactone, 4-hydroxy-2-nonenoic acid lactone, and 4-methylquinazoline, were identified for the first time in rice-containing products.

Journal of Agricultural and Food Chemistry published new progress about Bread (rice, gluten-free). 14667-55-1 belongs to class pyrazines, name is 2,3,5-Trimethylpyrazine, and the molecular formula is C7H10N2, Application of 2,3,5-Trimethylpyrazine.

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem