Month: November 2022

On November 28, 2018, Boergel, Jonas; Tanwar, Lalita; Berger, Florian; Ritter, Tobias published an article.Recommanded Product: 62163-09-1 The title of the article was Late-Stage Aromatic C-H Oxygenation. And the article contained the following:

Synthetic methods for oxidative aromatic C-O bond formation are sparse, despite their demand in metabolite synthesis for drug discovery and development. We report a novel methodol. for late-stage C-O bond formation of arenes. The reaction proceeds with excellent functional group tolerance even for highly functionalized substrates. The resulting aryl mesylates provide access to potential human metabolites of pharmaceuticals, and may be used directly to install a C-F bond to block metabolic hotspots. A charge-transfer interaction between the reagent bis(methanesulfonyl) peroxide and the substrate arenes may be relevant for the chemoselective functionalization of arenes over other functional groups. The experimental process involved the reaction of 5-Chloroquinoxaline(cas: 62163-09-1).Recommanded Product: 62163-09-1

The Article related to late stage aromatic oxygenation bismethanesulfonyl peroxide, aryl mesylate preparation, General Organic Chemistry: Synthetic Methods and other aspects.Recommanded Product: 62163-09-1

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Wu, Yizi; Wei, Weiwei; Yang, Huawu; Chen, Zengping; Zou, You; Li, Yanchun; Tuo, Suxing; Yin, Shuangfeng; Zhong, Kejun published an article in 2018, the title of the article was Gas chromatography-mass spectrometry data analysis algorithm based on sparse model and its application in resolving severely overlapped peaks.Formula: C8H10N2 And the article contains the following content:

A gas chromatog.-mass spectrometry (GC-MS) data anal. algorithm is proposed. The mass spectrum at the top of the chromatog. peak is the spectrum to be solved. A certain amount of related reference spectra is retrieved from the spectral library, and then, the equation of the chromatog. response value of each pure component is solved. A step-by-step strategy is used for the mass spectra retrieval. Firstly, an efficient indexing technol. is used for rough selection, and then, the “strong peak out with high probability” and the “extrusion” rules are used to exclude more unrelated mass spectra. A regression algorithm based on a sparse model is proposed to solve the equation of the chromatog. response value. Compared with the traditional algorithm, this algorithm can extract the main structure of the spectrum to be solved, and avoid over-fitting. The exptl. results show that the proposed algorithm has a higher accuracy and smaller residual reference spectrum set, and the sparse model achieves satisfactory exptl. results in the anal. of severely overlapped peaks. The proposed method provides an effective solution for resolving overlapped peaks, especially severely overlapped peaks, in GC-MS data. The experimental process involved the reaction of 5,6,7,8-Tetrahydroquinoxaline(cas: 34413-35-9).Formula: C8H10N2

The Article related to gc ms data analysis algorithm, gas chromatography-mass spectrometry (gc-ms), mass spectrometry retrieval, severely overlapped peaks, sparse model, Organic Analytical Chemistry: Determinations and other aspects.Formula: C8H10N2

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

On March 31, 2004, Baker, Richard R.; Bishop, Louise J. published an article.Application of 34413-35-9 The title of the article was The pyrolysis of tobacco ingredients. And the article contained the following:

Relationships between tobacco components and smoke products are complex and often difficult to unravel. Pyrolysis experiments have commonly been used to establish such relationships. However, unless they are performed under dynamic conditions that are relevant to those that occur during tobacco burning, results can be obtained which have little resemblance to those obtained during cigarette smoking. The relevance of pyrolysis experiments to the behavior of tobacco ingredients in a burning cigarette is considered. Based on the temperature, heating rate, oxygen levels and gas flow conditions that occur inside the burning zone of a cigarette, together with a review of relevant pyrolysis and smoking experiments, a set of pyrolysis conditions has been developed that approximates those occurring in the pyrolysis region of the burning cigarette. The conditions include heating the sample at 30° s-1 from 300 to 900° under a flow of 9% oxygen in nitrogen. Experiments on the pyrolytic behavior of eleven relatively volatile substances under these conditions give results that are in good agreement with results from thirteen published studies in which cigarettes incorporating labeled versions of the substances were smoked. Subsequently, 291 single-compound tobacco ingredients have been pyrolyzed under this set of conditions, most of which are relatively volatile. This enables the behavior of these ingredients in a burning cigarette to be estimated in terms of intact transfer to mainstream smoke vs. pyrolytic decomposition It is predicted that almost a third of the substances would transfer to mainstream smoke at least 99% intact, and almost two-thirds would transfer 95% intact. Where pyrolytic decomposition does occur, the products are listed together with an estimate of the levels in smoke that would arise from the ingredient. The experimental process involved the reaction of 5,6,7,8-Tetrahydroquinoxaline(cas: 34413-35-9).Application of 34413-35-9

The Article related to cigarette tobacco pyrolysis volatile substance decomposition, Mammalian Pathological Biochemistry: Oncology and other aspects.Application of 34413-35-9

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

On November 1, 2006, Johnson, Brett A.; Xu, Zhe; Pancoast, Paige; Kwok, Jennifer; Ong, Joan; Leon, Michael published an article.Category: quinoxaline The title of the article was Differential specificity in the glomerular response profiles for alicyclic, bicyclic, and heterocyclic odorants. And the article contained the following:

As part of our ongoing effort to relate stimulus to response in the olfactory system, we tested the hypothesis that the unique chem. structures and odors of various cyclic odorants would be associated with unique spatial response patterns in the glomerular layer of the rat olfactory bulb. To this end, rats were exposed to sets of odorants, including monocyclic hydrocarbons, bicyclic compounds, and various heterocyclic structures containing oxygen or nitrogen in the ring. Relative activity across the entire layer was assessed by mapping uptake of 2-deoxyglucose into anatomically standardized data matrixes. Whereas monocyclic hydrocarbons evoked patterns similar to those evoked by open-chained hydrocarbon odorants, a set of bicyclic compounds with structures and odors similar to camphor evoked uptake in paired ventral domains not previously associated with any other odorant chem. structures. Despite their unique odors as judged by humans, heterocyclic odorants either evoked uptake in previously characterized areas corresponding to their functional groups or stimulated weak or patchy patterns involving isolated glomeruli. Although the patchiness of the patterns may be partially related to the rigidity of the compounds, which would be expected to restrict their interactions to only a few receptors, the weakness of the patterns suggests the possibility of species-specific odorant representations. We conclude that, whereas some of the novel cyclic structures indeed were represented by unique patterns in the rat bulb, other unique structures were poorly represented, even when they evoked intense and unique odors in humans. The experimental process involved the reaction of 5,6,7,8-Tetrahydroquinoxaline(cas: 34413-35-9).Category: quinoxaline

The Article related to alicyclic bicyclic heterocyclic odorant olfactory bulb glomerulus olfaction, hydrocarbon lactone furan pyridine pyrazine olfactory glomerulus, Mammalian Biochemistry: General Physiological Chemistry and other aspects.Category: quinoxaline

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

On October 31, 1980, Hollstein, Ulrich; Krisov, Galen E. published an article.Category: quinoxaline The title of the article was Carbon-13 NMR studies on some 5-substituted quinoxalines. And the article contained the following:

The 11 quinoxalines I (R = NO2, NH2, CO2H, OMe, Me, OH, F, Cl, Br, I, CN) were prepared and their 13C NMR were recorded in (D3C)2SO and assigned. The observed chem. shifts agree with those calculated from C6H6 substituent parameters and are close to those of corresponding carbons in 1-substituted phenazines and naphthalenes, except for the quinoxaline C-4a and C-8a which, due to their proximity to N, are downfield relative to those of the naphthalenes. The spectrum of I (R = F) was recorded in a range of solvents: in each case there was a low 2J(CF) for C-4a and no C-F spin-spin splitting for the 3-bond coupling of C-8a. Linear relationships exist between the Q parameter of the substituent and the chem. shift of C-4a, -5, and -6 and between the chem. shift of C-8 and the Hammet σp parameter of the substituent. The experimental process involved the reaction of 5-Chloroquinoxaline(cas: 62163-09-1).Category: quinoxaline

The Article related to nmr carbon quinoxaline substituent effect, Physical Organic Chemistry: Spectral and Related Studies and other aspects.Category: quinoxaline

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

On January 31, 1981, Poradowska, Henryka; Kaniewska, Alicja published an article.Formula: C8H5ClN2 The title of the article was The mass spectra of halo derivatives of quinoxaline. And the article contained the following:

The mass spectra of 17 haloquinoxalines I (R-R3 = H, Br, Cl, Me) were recorded. All I gave mol.-ion peaks with typical isotopic ratios. The fragmentation path depended on the position of the halo atom: pyrazine-bound halo derivatives fragmented primarily via elimination of a halogen radical with insignificant cyanogen halide elimination, whereas benzene-bound halo derivatives fragmented via successive elimination of 2 RCN mols. (R = H, Me). The experimental process involved the reaction of 5-Chloroquinoxaline(cas: 62163-09-1).Formula: C8H5ClN2

The Article related to haloquinoxaline mass spectra, quinoxaline halo mass spectra, methylquinoxaline halo mass spectra, Physical Organic Chemistry: Spectral and Related Studies and other aspects.Formula: C8H5ClN2

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

On May 2, 2003, Skupinska, Krystyna A.; McEachern, Ernest J.; Baird, Ian R.; Skerlj, Renato T.; Bridger, Gary J. published an article.Electric Literature of 34413-35-9 The title of the article was Enzymatic Resolution of Bicyclic 1-Heteroarylamines Using Candida antarctica Lipase B. And the article contained the following:

Candida antarctica lipase B has been used to kinetically resolve a structurally diverse series of bicyclic 1-heteroaryl primary amines, e.g. 8-amino-5,6,7,8-tetrahydroquinoline, 5-amino-5,6,7,8-tetrahydroquinoxaline, etc., by enantioselective acetylation. High yields of either enantiomer could be obtained with excellent enantioselectivity (90-99% ee), while the undesired enantiomer could, in some cases, be recycled by thermal racemization. The absolute stereochem. of the products was confirmed by an X-ray crystallog. The experimental process involved the reaction of 5,6,7,8-Tetrahydroquinoxaline(cas: 34413-35-9).Electric Literature of 34413-35-9

The Article related to amine heteroaryl bicyclic acetylation enzymic resolution lipase, Heterocyclic Compounds (More Than One Hetero Atom): General and other aspects.Electric Literature of 34413-35-9

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

On October 18, 1988, Kato, Shozo; Ishizaki, Masahiko; Osada, Seiji published a patent.Recommanded Product: 62163-09-1 The title of the patent was Preparation of halogenated heterocydes as intermediates for agrochemicals and drugs. And the patent contained the following:

Polyhalogenated heterocycles are dehalogenated in H2O and/or alcs. in the presence of Fe powder and inorganic bases to give halogenated heterocycles. The experimental process involved the reaction of 5-Chloroquinoxaline(cas: 62163-09-1).Recommanded Product: 62163-09-1

The Article related to halogenated heterocycle intermediate drug agrochem, dehalogenation polyhaloheterocycle, Heterocyclic Compounds (More Than One Hetero Atom): General and other aspects.Recommanded Product: 62163-09-1

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

On December 31, 1998, El-Kayati, S. M.; Fadel, H. H. M.; Abdel Mageed, M. A.; Farghal, S. A. published an article.Name: 5,6,7,8-Tetrahydroquinoxaline The title of the article was Heat and storage effects on the flavor of peanuts. And the article contained the following:

The peanut varieties, Giza 4 and Giza 5 were subjected to different heat treatments such as drying in solar drier at air speed 0.5 and 2 m/s with average temperature 45 and 60° and heating in oven at 120 and 150°. The sensory evaluation of the 2 varieties showed insignificant differences among varieties and heating processes. A correlation between the sensory and instrumental data was found. The high sensory scores of samples heated at 150° were attributed to the presence of high concentration of pyrazines which were thought to contribute to flavor and aroma of fresh roasted peanut. A comparative study between the main chem. classes retained in peanut samples after storage for 3 mo at room temperature showed that the aldehydes derived lipids increased in the solar dried samples. The antioxidative components produced via Maillard reaction resulted in oxidative stability of the samples heated in oven. The experimental process involved the reaction of 5,6,7,8-Tetrahydroquinoxaline(cas: 34413-35-9).Name: 5,6,7,8-Tetrahydroquinoxaline

The Article related to peanut flavor heat storage volatile, Food and Feed Chemistry: Fruits, Vegetables, Legumes, and Nuts and other aspects.Name: 5,6,7,8-Tetrahydroquinoxaline

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Ji, Xiao-dong; Zhao, Ya-li; Wu, Guo-chen; Cai, Xian-kun published an article in 2010, the title of the article was Analysis of volatile aroma components of fried peanuts.Recommanded Product: 34413-35-9 And the article contains the following content:

Peanut is rich in nutrients and the flavor of its products varies according to the processing technol. Peanut was roasted, pressure steamed, extracted by simultaneous distillation and extraction (SED) and then condensed for GC-MS anal. of its volatile aroma components. Aldehydes, pyrazine, alc., ketone and hydroxybenzene were found in the volatile aroma of processed peanuts, with their contents for 53.29%, 14.66%, 6.13%, 1.03%, and 7.73%, resp. And pyridine, pyrrole, thiophene, and others accounted for 17.02%. Besides, two important fragrances, 2-acetyl-l-pyrroline and 2-methoxy-4-vinylphenol, were also detected in the volatile aroma of processed peanuts. The experimental process involved the reaction of 5,6,7,8-Tetrahydroquinoxaline(cas: 34413-35-9).Recommanded Product: 34413-35-9

The Article related to fried peanut volatile aroma component, Food and Feed Chemistry: Fruits, Vegetables, Legumes, and Nuts and other aspects.Recommanded Product: 34413-35-9

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider