Month: November 2022

Ogryzek, Malgorzata’s team published research in RSC Advances in 6 | CAS: 4604-72-2

RSC Advances published new progress about 4604-72-2. 4604-72-2 belongs to pyrazines, auxiliary class Pyrazine,Amine,Amide, name is Pyrazine-2-carbothioamide, and the molecular formula is C5H5N3S, Computed Properties of 4604-72-2.

Ogryzek, Malgorzata published the artcileCoordination chemistry of pyrazine derivatives analogues of PZA: design, synthesis, characterization and biological activity, Computed Properties of 4604-72-2, the publication is RSC Advances (2016), 6(57), 52009-52025, database is CAplus.

Ru(III) complexes with pyrazine derivatives: 2,3-bis(2-pyridyl)pyrazine (DPP), pyrazine-2-amidoxime (PAOX), pyrazine-2-thiocarboxamide (PTCA) and 2-amino-5-bromo-3-(methylamino)pyrazine (ABMAP) have been prepared Characterization of the compounds was acquired using UV-Vis and FT-IR spectroscopy, elemental anal., conductivity and electrochem. measurements as well as thermogravimetric studies. The ligand field parameters, Δ0 (splitting parameter), B (Racah parameter of interelectronic repulsion) and β (nephelauxetic ratio) were calculated The stabilities of the Ru(III) complexes have also been confirmed by spectrophotometric titration methods in acetonitrile and water solutions The data showed that the examined compounds are stable both in solution and solid states, which was also confirmed by the values of their stability constants found. Moreover, the mol. structures of the complexes have been optimized using AM1 and PM3 methods and this supported octahedral geometry around the Ru(III) ion. The min. inhibitory (MIC) and min. bactericidal concentration (MBC) for synthesized complexes were studied against two Gram (+) bacteria, two Gram (-) bacteria and fungi – three reference strains of Candida albicans. The results show that [RuCl(PAOX)2(OH2)]Cl2 display antifungal activity.

RSC Advances published new progress about 4604-72-2. 4604-72-2 belongs to pyrazines, auxiliary class Pyrazine,Amine,Amide, name is Pyrazine-2-carbothioamide, and the molecular formula is C5H5N3S, Computed Properties of 4604-72-2.

Referemce:
https://en.wikipedia.org/wiki/Pyrazine,
Pyrazine | C4H4N2 – PubChem

Biedulska, Malgorzata’s team published research in Journal of Molecular Liquids in 296 | CAS: 4604-72-2

Journal of Molecular Liquids published new progress about 4604-72-2. 4604-72-2 belongs to pyrazines, auxiliary class Pyrazine,Amine,Amide, name is Pyrazine-2-carbothioamide, and the molecular formula is C5H5N3S, SDS of cas: 4604-72-2.

Biedulska, Malgorzata published the artcileComparative solution equilibria studies of complex formation between Ir(III) ion and antituberculosis drug analogues: Spectroscopic, potentiometric and conductometric approach, SDS of cas: 4604-72-2, the publication is Journal of Molecular Liquids (2019), 111887, database is CAplus.

The detailed studies concerning the binding mode of bioactive ligands: pyrazine-2-carboxamide (PZA), pyrazine-2-thiocarboxamide (PTCA) and pyrazine-2-amidoxime (PAOX) have been performed by using three independent techniques: UV-Vis spectroscopy, potentiometry and conductometry. The composition and stability constants of new series Ir(III) complexes with antituberculosis drug and its structural analogs have been determined in aqueous and nonaqueous solutions The hypsochromic shifts of bands and appearance of new peaks during UV-Vis spectrophotometric titration confirmed the interaction of Ir(III) ion with bioligands. In the studied pH range activation of pyrazine derivatives began complexation process. The sharply changed of conductimetric curves slope clearly demonstrated that the ML2 type complexes formation with relatively high stability are favored. Under the exptl. conditions, it was found that metal ion interact with ligands leading to the formation of pos. charged complexes. The gradual and cumulative stability constants of Ir(III) coordination compounds have been determined The stability order of Ir(III)- PY systems studied is as follows: PAOX > PZA > PTCA. The anal. of formation equilibrium revealed that mononuclear Ir(III) coordination compounds with metal to ligand molar ratio equals 1:2 are preferable with prominently high solution stability. Comparison of stability constants values showed that an increase in the efficiency of the reaction between metal ion and bioligands was observed with elongation of substituent chain. In the binary complexes, the bidentate nature of bioactive ligands and participation of amine and heterocyclic nitrogens in coordination of central ion were confirmed.

Journal of Molecular Liquids published new progress about 4604-72-2. 4604-72-2 belongs to pyrazines, auxiliary class Pyrazine,Amine,Amide, name is Pyrazine-2-carbothioamide, and the molecular formula is C5H5N3S, SDS of cas: 4604-72-2.

Referemce:
https://en.wikipedia.org/wiki/Pyrazine,
Pyrazine | C4H4N2 – PubChem

Cressina, Elena’s team published research in Chemical Science in 2 | CAS: 59944-75-1

Chemical Science published new progress about 59944-75-1. 59944-75-1 belongs to pyrazines, auxiliary class Other Aromatic Heterocyclic,Amine, name is Thieno[2,3-b]pyrazin-7-amine, and the molecular formula is C6H5N3S, Synthetic Route of 59944-75-1.

Cressina, Elena published the artcileFragment screening against the thiamine pyrophosphate riboswitch thiM, Synthetic Route of 59944-75-1, the publication is Chemical Science (2011), 2(1), 157-165, database is CAplus.

Riboswitches are regions of mRNA that bind selectively certain metabolites, thereby regulating gene expression. We have developed a method, which uses a combination of biophys. techniques (equilibrium dialysis, waterLOGSY and T2 relaxation-edited NMR spectroscopy and isothermal titration calorimetry) that allows screening and identification of novel ligands for riboswitches. By this method a library of 1300 fragments was screened on the E. coli thiamin pyrophosphate (TPP) riboswitch thiM, resulting in the identification of 17 hits. The compounds showed KD values from 22 to 670 μM, with four compounds having KD values <100 μM. The fragments are structurally diverse and their ligand efficiency indicates good prospects for structure-guided elaboration. In addition, a riboswitch functional assay based on in vitro transcription translation (IVTT) of the reporter gene luciferase was developed. This assay system is an alternative to in vivo assays and constitutes a valuable tool to determine the effect of small mols. on riboswitch-regulated gene expression.

Chemical Science published new progress about 59944-75-1. 59944-75-1 belongs to pyrazines, auxiliary class Other Aromatic Heterocyclic,Amine, name is Thieno[2,3-b]pyrazin-7-amine, and the molecular formula is C6H5N3S, Synthetic Route of 59944-75-1.

Referemce:
https://en.wikipedia.org/wiki/Pyrazine,
Pyrazine | C4H4N2 – PubChem

Novacek, Libor’s team published research in Acta Facultatis Pharmaceuticae Universitatis Comenianae in 27 | CAS: 4604-72-2

Acta Facultatis Pharmaceuticae Universitatis Comenianae published new progress about 4604-72-2. 4604-72-2 belongs to pyrazines, auxiliary class Pyrazine,Amine,Amide, name is Pyrazine-2-carbothioamide, and the molecular formula is C5H5N3S, Computed Properties of 4604-72-2.

Novacek, Libor published the artcileAntituberculotics. XII. Functional derivatives of ring-substituted pyrazinecarboxylic acids, Computed Properties of 4604-72-2, the publication is Acta Facultatis Pharmaceuticae Universitatis Comenianae (1975), 27(5), 73-87, database is CAplus.

The most active of a series of 20 ring-substituted pyrazinecarboxylic acid derivatives tested in vitro against Mycobacterium tuberculosis H37Rv, M. avium, and M. kansasii were 3-hydrazinopyrazine-2-carboxylic acid hydrazide (I) [21279-74-3], 5-bromopyrazine-2-carboxamide [36070-84-5], and 5-(vanillidenehydrazino)pyrazine-2-carboxylic acid 2-vanillidenehydrazide [36805-05-7]. For example, I was active against M. tuberculosis and M. kansasii at 25 μg/ml and against M. avium at 50 μg/ml. The acid hydrazides tested were generally more active than amides and thioamides. None of 3 of the most active compounds, tested in vivo in mice, was as potent as pyrazinamide [98-96-4].

Acta Facultatis Pharmaceuticae Universitatis Comenianae published new progress about 4604-72-2. 4604-72-2 belongs to pyrazines, auxiliary class Pyrazine,Amine,Amide, name is Pyrazine-2-carbothioamide, and the molecular formula is C5H5N3S, Computed Properties of 4604-72-2.

Referemce:
https://en.wikipedia.org/wiki/Pyrazine,
Pyrazine | C4H4N2 – PubChem

Patinote, Cindy’s team published research in European Journal of Medicinal Chemistry in 138 | CAS: 117718-92-0

European Journal of Medicinal Chemistry published new progress about 117718-92-0. 117718-92-0 belongs to pyrazines, auxiliary class Other Aromatic Heterocyclic,Bromide,Amine, name is 3-Bromoimidazo[1,2-a]pyrazin-8-amine, and the molecular formula is C6H5BrN4, Related Products of pyrazines.

Patinote, Cindy published the artcileImidazo[1,2-a]pyrazine, Imidazo[1,5-a]quinoxaline and Pyrazolo[1,5-a]quinoxaline derivatives as IKK1 and IKK2 inhibitors, Related Products of pyrazines, the publication is European Journal of Medicinal Chemistry (2017), 909-919, database is CAplus and MEDLINE.

Herein, the synthesis of twenty-one new compounds based on the imidazo[1,2-a]pyrazine, imidazo[1,5-a]quinoxaline or pyrazolo[1,5-a]quinoxaline structures is reported. Their potential to inhibit IKK1 and IKK2 activities is also tested.

European Journal of Medicinal Chemistry published new progress about 117718-92-0. 117718-92-0 belongs to pyrazines, auxiliary class Other Aromatic Heterocyclic,Bromide,Amine, name is 3-Bromoimidazo[1,2-a]pyrazin-8-amine, and the molecular formula is C6H5BrN4, Related Products of pyrazines.

Referemce:
https://en.wikipedia.org/wiki/Pyrazine,
Pyrazine | C4H4N2 – PubChem

Zhang, Lijie’s team published research in Applied and Environmental Microbiology in 2019-12-31 | CAS: 14667-55-1

Applied and Environmental Microbiology published new progress about 2,3,5-trimethylpyrazine; 2,5-dimethylpyrazine; Bacillus subtilis; alkylpyrazine; synthesis mechanism. 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.

Zhang, Lijie published the artcileAn alkylpyrazine synthesis mechanism involving l-threonine-3-dehydrogenase describes the production of 2,5-dimethylpyrazine and 2,3,5-trimethylpyrazine by Bacillus subtilis, Quality Control of 14667-55-1, the main research area is 2,3,5-trimethylpyrazine; 2,5-dimethylpyrazine; Bacillus subtilis; alkylpyrazine; synthesis mechanism.

Alkylpyrazines are important contributors to the flavor of traditional fermented foods. Here, we studied the synthesis mechanisms of 2,5-dimethylpyrazine (2,5-DMP) and 2,3,5-trimethylpyrazine (TMP). Substrate addition, whole-cell catalysis, stable isotope tracing experiments, and gene manipulation revealed that l-threonine is the starting point involving l-threonine-3-dehydrogenase (TDH) and three uncatalyzed reactions to form 2,5-DMP. TDH catalyzes the oxidation of l-threonine. The product of this reaction is l-2-amino-acetoacetate, which is known to be unstable and can decarboxylate to form aminoacetone. It is proposed that aminoacetone spontaneously converts to 2,5-DMP in a pH-dependent reaction, via 3,6-dihydro-2,5-DMP. 2-Amino-3-ketobutyrate CoA (CoA) ligase (KBL) catalyzes the cleavage of l-2-amino-acetoacetate, the product of TDH, into glycine and acetyl-CoA in the presence of CoA. Inactivation of KBL could improve the production of 2,5-DMP. Besides 2,5-DMP, TMP can also be generated by Bacillus subtilis 168 by using l-threonine and d-glucose as the substrates and TDH as the catalytic enzyme.

Applied and Environmental Microbiology published new progress about 2,3,5-trimethylpyrazine; 2,5-dimethylpyrazine; Bacillus subtilis; alkylpyrazine; synthesis mechanism. 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

Wang, Chunmiao’s team published research in Water Research in 2020-09-01 | CAS: 14667-55-1

Water Research published new progress about Air. 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.

Wang, Chunmiao published the artcilePyrazines: A diverse class of earthy-musty odorants impacting drinking water quality and consumer satisfaction, Quality Control of 14667-55-1, the main research area is pyrazine water quality consumer satisfaction coagulation sedimentation; Descriptors; Drinking water; Earthy-musty odor; Occurrence; Odor threshold concentrations; Pyrazines.

The presence of earthy-musty odors in drinking water is a major concern for water suppliers and consumers worldwide. While geosmin and 2-methylisoborneol are the most studied earthy-musty odor-causing compounds, pyrazine and its alkyl and methoxy compounds possess similar odors and are widely distributed in nature, foods, and beverages. In this study, odor characteristics of pyrazines and their presence in natural and treated waters were determined Pyrazine, 2,6-dimethyl-pyrazine (DMP), 2,3,5-trimethyl-pyrazine (TrMP), 2-ethyl-5(6)-methyl-pyrazine (EMP), 2,3,5,6-tetramethyl-pyrazine (TeMP), 2-isobutyl-3-methoxy-pyrazine (IBMP) and 2-isopropyl-3-methoxy-pyrazine (IPMP) were measured in source and finished drinking water across China. 2-Methoxy-3,5-dimethyl-pyrazine (MDMP), IBMP, and IPMP were investigated in rivers in Virginia, USA. The results showed that “”musty”” and “”sweet”” were the most common descriptors for pyrazine, DMP, MDMP, TrMP, and TeMP. While IBMP and IPMP were never detected in 140 source or drinking water samples from across China, pyrazine, DMP, MDMP, TrMP, and TeMP occurred throughout with concentrations of n.d.-62.2 ng/L-aq in source water and n.d.-39.6 ng/L-aq in finished water. IBMP, IPMP, and MDMP were present in two Virginia rivers; MDMP occurred in 18% of the samples with concentrations of n.d.-4.4 ng/L, many of which were above the aqueous odor threshold of 0.043 ng/L MDMP.

Water Research published new progress about Air. 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

Chiang, Jie Hong’s team published research in Food Research International in 2019-09-30 | CAS: 14667-55-1

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

Chiang, Jie Hong published the artcileChanges in the physicochemical properties and flavour compounds of beef bone hydrolysates after Maillard reaction, Safety of 2,3,5-Trimethylpyrazine, the main research area is bone hydrolyzate flavor compound physicochem property Maillard reaction; Beef bone hydrolysates; Free amino acids; Maillard reaction; Peptide contents; Volatile compounds.

This study investigated the changes in physicochem. properties and volatile compounds of beef bone hydrolyzates during heat treatment as a result of the Maillard reaction. Five beef bone hydrolyzates obtained from single (P-Protamex, B-bromelain, and F-Flavourzyme) and simultaneous (P + F and B + F) enzymic hydrolysis treatments were combined with ribose in aqueous solutions and heated at 113°C to produce MRPs. Total free amino acids decreased after heat treatment indicating the occurrence of the MR. MRPs showed a decrease in pH and an increase in browning intensity as the degree of hydrolysis of hydrolyzates increased. The volatiles compounds generated during heat treatment were evaluated using GC-MS with headspace SPME sampling. A total of 40 volatile compounds were identified in all MRPs and their concentration were found to increase with increasing degree of hydrolysis. Pyrazines were the most abundant class of compounds produced as a result of the MR. F-MRP showed the highest peak area intensity for 17 volatile compounds in single hydrolysis treatment followed by heat treatment. There was also no significant difference in those major volatile compounds between F-MRP and P + F-MRP or B + F-MRP from simultaneous hydrolysis treatment after heating. Hence, the use of Flavourzyme alone to increase the flavor intensity of beef bone extract is recommended. Overall results indicated that enzymic hydrolysis and MR could be used to modify the flavor characters of beef bone extract

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

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Vierck, Kelly R.’s team published research in Meat and Muscle Biology in 2019 | CAS: 14667-55-1

Meat and Muscle Biology published new progress about Beef. 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.

Vierck, Kelly R. published the artcileThe impact of enhancement, degree of doneness, and USDA quality grade on beef flavor development, Synthetic Route of 14667-55-1, the main research area is impact enhancement degree doneness USDA quality grade; beef flavor development.

The objective of this study was to determine the impact of enhancement, degree of doneness (DOD), and USDA quality grade on beef volatile flavor compounds from cooked strip loin steaks. This study also aimed to evaluate relationships between volatile compounds and consumer sensory responses. Beef strip loins (n = 72; 24/grade) of 3 quality grades (USDA Prime, Low Choice, and Low Select) were enhanced (8% of green weight with brine containing 0.35% salt and 0.4% sodium phosphate) or not enhanced, and cooked to 3 DOD (Rare: 60°C; Medium: 71°C; Very Well Done: 83°C) before volatile anal. Volatile compounds were evaluated through a split-plot design where enhancement level and quality grade were used as the whole plot factors and DOD served as the subplot factor. Principal component anal. (PCA) was utilized to explore relationships between volatile compounds, consumer response, and treatments. The majority of compounds (n = 32) were impacted (P < 0.05) by the interaction between DOD x enhancement x quality grade. Four compounds- methanethiol, dimethyl-disulfide, methyl-benzene, and acetic acid were affected (P < 0.05) by enhancement x DOD. Two compounds-dimethyl sulfone and d-limonene, were impacted (P < 0.05) by quality grade x enhancement. Phenylacetaldehyde and hexanoic acid, Me ester was affected (P < 0.05) by the interaction of USDA quality grade x DOD. The DOD main effect was only implicated in Maillard products (P < 0.05), including 2-methylbutanal, a Strecker aldehyde, and 2 pyrazines (methyl-pyrazine and trimethylpyrazine). Nonanal was the only compound impacted (P < 0.05) by a quality grade effect. No enhancement main effects were observed for any compounds (P > 0.05). In agreement, PCA indicated volatile compound production was primarily driven by degree of doneness and quality grade. There was no strong link between enhancement and beef volatile flavor compound development, despite the dramatically improved flavor liking scores from consumers.

Meat and Muscle Biology published new progress about Beef. 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

Dach, Anna’s team published research in Journal of Agricultural and Food Chemistry in 2021-02-10 | CAS: 14667-55-1

Journal of Agricultural and Food Chemistry published new progress about Dough. 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.

Dach, Anna published the artcileChanges in the Concentrations of Key Aroma Compounds in Oat (Avena sativa) Flour during Manufacturing of Oat Pastry, Quality Control of 14667-55-1, the main research area is aroma compound Avena oat flour pastry; 2-acetyl-1-pyrroline; 2-acetyltetrahydropyridine; Avena sativa; oat flour; oat pastry; odor activity value; stable isotope dilution assay.

Application of the aroma extract dilution anal. on the volatiles isolated from oat flour revealed 30 aroma-active compounds in the flavor dilution (FD) factor range of 2-8192, among which oat-flour-like smelling (E,E,Z)-2,4,6-nonatrienal showed by far the highest FD factor. Quantitation performed by stable isotope dilution assays and a calculation of odor activity values (OAV; ratio of the concentration to odor threshold) of 23 odorants showed an OAV of above 1. Among them, vanillin, (E,E,Z)-2,4,6-nonatrienal, 2-acetyl-1-pyrroline, 3-methylbutanoic acid, and 2-methoxy-4-vinylphenol showed the highest OAVs. In a heated (70°C for 30 min) oat dough prepared by kneading the oat flour in the presence of sucrose and water, 34 aroma-active compounds were identified, among which 17 compounds appeared with an OAV of ≥1. During frying, the weak cereal-like aroma of the oat flour and the oat dough was changed with the generation of an intense roasty, popcorn-like aroma attribute. A comparison to recently published data on oat pastry prepared by toasting of the same dough showed a clear increase in the overall aroma intensity from flour to pastry, in particular, in the popcorn-like, roasty odor impression. Especially considerable increases in the concentrations of the popcorn-like smelling compounds 2-acetyl-1-pyrroline, 2-acetyl-3,4,5,6- and 2-acetyl-1,4,5,6-tetrahydropyridine, 2-propionyl-1-pyrroline, and 2-acetyl-2-thiazoline were measured. In addition, the concentrations of the Strecker aldehydes 2- and 3-methylbutanal, phenylacetaldehyde, and 3-(methyldithio)propanal were also much increased during the toasting process. In contrast, in line with the overall aroma profile, particularly the concentration of the oat-like smelling compound (E,E,Z)-2,4,6-nonatrienal was decreased during processing. The formation and precursors of the key aroma compounds are discussed.

Journal of Agricultural and Food Chemistry published new progress about Dough. 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