Tag: 100-200

Reaction of 1-ethoxyalylmethylpyrido[2,3-b]pyrazinium bromide with ammonium acetate: synthesis of imidazo[1′,2′:1,2]pyrido[5,6-b]pyrazines was written by Blache, Yves;Gueiffier, Alain;Chavignon, Olivier;Elhakmaoui, Ahmed;Viols, Henry;Teulade, Jean Claude;Milhavet, Jean Claude;Dauphin, Gerard;Chapat, Jean Pierre. And the article was included in Heterocycles in 1994.Recommanded Product: Pyrido[2,3-b]pyrazine This article mentions the following:

The synthesis of some imidazo[1,2′:1,2]pyrido[5,6-b]pyrazines I (R¹ = H, Me, R² = H; R¹ = R² = Me) by treatment of quaternary salts of pyrido[2,3-b]pyrazines II (R³ = H) with ammonium acetate in AcOH media is described. In the experiment, the researchers used many compounds, for example, Pyrido[2,3-b]pyrazine (cas: 322-46-3Recommanded Product: Pyrido[2,3-b]pyrazine).

Pyrido[2,3-b]pyrazine (cas: 322-46-3) belongs to pyrazine derivatives. Pyrazinesare six-membered aromatic heterocyclic organic compounds with two nitrogen atoms at 1,4-positions. Pyrazine is a weaker base (pKb = 13.4) than pyridine (pKb = 8.8), pyrimidine (pKb = 12.7). A large number of pyrazine derivatives are known for their antitumor, antibiotic, anticonvulsant, antituberculosis, and diuretic activities.Recommanded Product: Pyrido[2,3-b]pyrazine

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Self-consistent field molecular orbital calculations of ultraviolet electronic spectra of azanaphthalenes with the variable 灏?approximation was written by Tinland, Bernard. And the article was included in Theoretica Chimica Acta in 1967.Product Details of 322-46-3 This article mentions the following:

The stable crystal field M.O. calculations of uv electronic spectra of 10 azonaphthalenes with the variable 灏?approximation (K. Nishimoto, et al., 1966) are presented. The transition energies and bond lengths of these mols. were calculated and the results are in satisfactory agreement with experiment In the experiment, the researchers used many compounds, for example, Pyrido[2,3-b]pyrazine (cas: 322-46-3Product Details of 322-46-3).

Pyrido[2,3-b]pyrazine (cas: 322-46-3) belongs to pyrazine derivatives. Pyrazine heterocycles and their benzo derivatives possess many interesting properties, including chemical reactivity profiles, and have diverse applications in total synthesis, medicine, chemical biology, materials, dyes, and imaging. Pyrazines are chemical compounds (technically called 閳ユ笗ethoxypyrazines閳? found in grape skin and stems that are responsible for many 閳ユ笀reen閳?flavors in wine. Levels of pyrazines are dependent on viticultural practices, climate, and grape variety.Product Details of 322-46-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Design, synthesis and biological evaluation of thrombin inhibitors with 1,2,3,4-tetrahydrobenzo[4,5]imidazo[1,2-a]pyrazine nucleus was written by Chen, Dongxing;Shi, Jinyu;Chen, Qiufang;Zhang, Rui;Gong, Guoqing;Xu, Yungen;Zhu, Qihua. And the article was included in Gaodeng Xuexiao Huaxue Xuebao in 2017.HPLC of Formula: 75907-74-3 This article mentions the following:

Compound 1, a new thrombin inhibitor with 1,2,3,4-tetrahydrobenzo[4,5]imidazo[1,2-a]pyrazine nucleus, was selected as lead compound, and fourteen carbamate derivatives derivatives were designed and prepared Furthermore, a twin drug (11) was synthesized by coupling compound 1 with 2-hydroxymethyl-3,5,6-trimethylpyrazine (HTMP). The structures of all the target compounds were confirmed by ¹H-NMR, ¹³C-NMR and HRMS. Preliminary biol. activity test results indicated that all of the tested compounds exhibited a certain degree of inhibitory effect on thrombin-induced platelet aggregation, among which compound 4b [IC₅₀ = (0.11鍗?.08) 娓璵ol/L] showed better anti-platelet aggregation activity than dabigatran etexilate [IC₅₀ = (0.60鍗?.05) 娓璵ol/L]. The in vitro exptl. results in rat venous thrombosis model demonstrated compound 4b could significantly reduce thrombosis in a dose-response manner. Compound 11, which showed weak inhibitory effect on thrombin-induced platelet aggregation, also displayed comparable inhibitory effect on rat venous thrombosis with dabigatran etexilate. The study pointed out that the enhanced potency of compound 11 may be the synergetic effect on HTMP and compound 1 which were generated by hydrolysis in vivo. In the experiment, the researchers used many compounds, for example, (3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3HPLC of Formula: 75907-74-3).

(3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3) belongs to pyrazine derivatives. Pyrazine is an N-heterocyclic moiety, and it can be easily prepared from ethylenediamine and 1,2-diketone, 浼?hydroxyketone, 浼?methyl ketone. A number of pyrazine-based derivatives were used as dyes or fluorescent probes.HPLC of Formula: 75907-74-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Identification of hydroxymethylpyrazines using mass spectrometry was written by Bohman, Bjoern;Flematti, Gavin R.;Barrow, Russell A.. And the article was included in Journal of Mass Spectrometry in 2015.Quality Control of (3,5,6-Trimethylpyrazin-2-yl)methanol This article mentions the following:

Pyrazines are well-known natural products that are present in bacterial odors and food flavoring agents and are used as insect pheromones. Recently, a number of hydroxymethylpyrazines have been identified as thynnine wasp pheromones and orchid semiochems. that are essential for pollination in sexually deceptive plants. These compounds are present in low amounts in complex blends, making GC-MS (including high-resolution techniques) the method of choice for their structure elucidation. We report the EI mass spectra for 14 representative compounds and have found that based on characteristic fragmentations, it is possible to distinguish between different positional isomers of hydroxymethylpyrazines. The presence or absence of either [M – 17]⁺, [M – 18]^{+璺?/sup> or [M – 19]+ fragment species provides characteristic information to allow the distinction between the different isomers. Considering the importance of pyrazines as a group of bioactive natural products, and the recent findings of biol. activity for hydroxymethylpyrazines, our results presented here will aid the identification of these compounds in other biol. systems. Copyright 婕?2015 John Wiley & Sons, Ltd. In the experiment, the researchers used many compounds, for example, (3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3Quality Control of (3,5,6-Trimethylpyrazin-2-yl)methanol).}

(3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3) belongs to pyrazine derivatives. Pyrazine is a symmetrical molecule with point group D2h. Pyrazine is less basic than pyridine, pyridazine and pyrimidine. Pyrazine and a variety of alkylpyrazines are flavor and aroma compounds found in baked and roasted goods. Tetramethylpyrazine (also known as ligustrazine) is reported to scavenge superoxide anion and decrease nitric oxide production in human Granulocytes.Quality Control of (3,5,6-Trimethylpyrazin-2-yl)methanol

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Pyrazoles. 6. Synthesis of novel heteroaryl 4-pyrazolyl ketones was written by Hahn, Marianne;Heinisch, gottfried;Holzer, Wolfgang;Schwarz, Helga. And the article was included in Journal of Heterocyclic Chemistry in 1991.Electric Literature of C7H8N2O2 This article mentions the following:

Pyrazolyl ketones I (R = 2-, 3-, 4-pyridinyl, 3-, 4-pyridazinyl, 4-pyrimidinyl, 2-pyrazinyl, 2-, 3-thienyl, 4-bromo-2-thienyl) were prepared by lithiation and condensation of 4-bromopyrazole with RCO₂Et or with RCHO (R = 2-, 3-thienyl, 4-bromo-2-thienyl) followed by oxidation In the experiment, the researchers used many compounds, for example, Ethyl pyrazine-2-carboxylate (cas: 6924-68-1Electric Literature of C7H8N2O2).

Ethyl pyrazine-2-carboxylate (cas: 6924-68-1) belongs to pyrazine derivatives. Pyrazines are volatile compounds that are used in the cosmetic, food, flavor, and fragrance industries. Pyrazine and a variety of alkylpyrazines are flavor and aroma compounds found in baked and roasted goods. Tetramethylpyrazine (also known as ligustrazine) is reported to scavenge superoxide anion and decrease nitric oxide production in human Granulocytes.Electric Literature of C7H8N2O2

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Azanaphthalenes. I. Hueckel orbital calculations was written by Wait, S. C. Jr.;Wesley, John W.. And the article was included in Journal of Molecular Spectroscopy in 1966.Recommanded Product: 322-46-3 This article mentions the following:

Energy levels, wave functions, and charge ds. are reported for 74 azanaphthalenes. Calculations were performed by using the Hueckel method. Comparison of the lowest singlet-singlet transition with that calculated by the Pariser-Parr method is given for 21 compounds In the experiment, the researchers used many compounds, for example, Pyrido[2,3-b]pyrazine (cas: 322-46-3Recommanded Product: 322-46-3).

Pyrido[2,3-b]pyrazine (cas: 322-46-3) belongs to pyrazine derivatives. Pyrazines are part of several biologically active polycyclic compounds; examples are quinoxalines, phenazines; and the bio-luminescent natural products pteridines, flavins, and their derivatives. Pyrazine heterocycles and their benzo derivatives possess many interesting properties, including chemical reactivity profiles, and have diverse applications in total synthesis, medicine, chemical biology, materials, dyes, and imaging.Recommanded Product: 322-46-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Infrared spectra of heterocyclic compounds. VIII. Infrared spectra of substituted pyrazines and their N-oxides was written by Shindo, Hideyo. And the article was included in Chemical & Pharmaceutical Bulletin in 1960.Product Details of 6924-68-1 This article mentions the following:

Previous correlations of infrared spectra and structures of pyridine derivatives (loc. cit.) were extended to the pyrazine (I) ring system to determine the effect of the 2nd ring N. The infrared spectra of I, its H₂N (II), Me, Cl (III), Ac (IV), NC (V), HO₂C, EtO₂C (VI), and H₂NOC (VII) derivatives, and their 10 N-oxide derivatives were analyzed. VII dehydrated with POCl₃ and submitted to the Hofmann rearrangement gave, resp., V, b₃₁ 109-10°, and II, m. 117-18°. POCl₃ on the N-oxide of I gave III, b₃₁ 62-3°. Ester condensation of VI, m. 52-3°, gave IV, m. 79-80°. Oxidation of I and its derivatives with perhydrol gave their corresponding N-oxides (VIII) (compound oxidized, m.p. of VIII given): I, mono-oxide m. 108°, di-oxide m. 260°; III, 96°; IV, 184°; V, 153°; VI, 147°; VII, 293°. The characteristic N-O stretching frequencies (strong absorption in the region of 1250 and 1350 cm.^-1) of all these compounds were correlated to the nature of a substituent present, and the linear relation between the N-O frequency and the σ-value of a substituent in substituted pyridine N-oxides could be extended to that in substituted pyrazine N-oxides by applying the σ-value of ring N (0.93) and the N-oxide group (0.25) toward 4-position of pyridine for N-mono- and N,N’-dioxides, resp. The considerably higher frequency shift of the N-O frequency was shown to be characteristic for the Me group at β-position with respect to the N-oxide group. Ring and ring CH vibrations were discussed on the basis of the correlations found in the pyridine ring system. The splitting of the CO stretching frequency of ester group adjacent to ring N was pointed out and discussed. The infrared spectra of pyrimidine N-oxide, its 4-Me, 4,6-(PhS)Me, 4,6(PhO)Me, 4,6-(EtO)Me, 4,6-(MeO)Me, 4,6-(PhCH₃O)Me, 2,6,4-Me₂ (PhCH₂O), and 4-morpholino-6-methyl derivatives were also examined and discussed in comparison with the above results. In the experiment, the researchers used many compounds, for example, Ethyl pyrazine-2-carboxylate (cas: 6924-68-1Product Details of 6924-68-1).

Ethyl pyrazine-2-carboxylate (cas: 6924-68-1) belongs to pyrazine derivatives. Pyrazinesare six-membered aromatic heterocyclic organic compounds with two nitrogen atoms at 1,4-positions. Pyrazine is a weaker base (pKb = 13.4) than pyridine (pKb = 8.8), pyrimidine (pKb = 12.7). Pyrazine heterocycles and their benzo derivatives possess many interesting properties, including chemical reactivity profiles, and have diverse applications in total synthesis, medicine, chemical biology, materials, dyes, and imaging.Product Details of 6924-68-1

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthesis and protective effect of new ligustrazine-vanillic acid derivatives against CoCl₂-induced neurotoxicity in differentiated PC12 cells was written by Xu, Bing;Xu, Xin;Zhang, Chenze;Zhang, Yuzhong;Wu, GaoRong;Yan, Mengmeng;Jia, Menglu;Xie, Tianxin;Jia, Xiaohui;Wang, Penglong;Lei, Haimin. And the article was included in Chemistry Central Journal in 2017.Category: pyrazines This article mentions the following:

To develop new ligustrazine derivatives with neuroprotective effects, the synthesis of several ligustrazine-vanillic acid amide derivatives I [R = hydroxy, methylamino, 2-aminonaphthyl, etc.] and screened their protective effect on the injured PC12 cells damaged by CoCl₂. The results showed that most of the newly synthesized compounds I exhibited higher activity than ligustrazine, of which, compound I [R = 3-(dimethylamino)anilino] displayed the highest potency with EC₅₀ values of 17.39 ± 1.34 μM. Structure-activity relationships were studied. In the experiment, the researchers used many compounds, for example, (3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3Category: pyrazines).

(3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3) belongs to pyrazine derivatives. Pyrazines are volatile compounds that are used in the cosmetic, food, flavor, and fragrance industries. Pyrazine heterocycles and their benzo derivatives possess many interesting properties, including chemical reactivity profiles, and have diverse applications in total synthesis, medicine, chemical biology, materials, dyes, and imaging.Category: pyrazines

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Coordination ambivalence and fluxional behavior in mono- and binuclear pentacarbonyltungsten complexes of pteridine and its deaza derivatives was written by Bessenbacher, Christian;Kaim, Wolfgang. And the article was included in Journal of Organometallic Chemistry in 1989.HPLC of Formula: 322-46-3 This article mentions the following:

WL(CO)₅ (L = pteridine (pte), 1,5-naphthyridine, (npt), 1,4,5-triazanaphthalene (tan), 1,4,6-triazanaphthalene) and W₂(CO)₁₀L¹ (L¹ = pt, npt) were prepared Unambiguous identification of coordination sites was only possible by use of high-resolution ¹H NMR because the chem. shifts and spin-spin coupling constants are characteristically affected by W(CO)₅-coordination to neighboring N centers. Fluxional behavior with respect to the peri coordination sites was observed for W(CO)₅(1,4,5-tan) and W(CO)₁₀(pte). Competition between the more basic pyridine or pyrimidine and the better π backdonating pyrazine N centers leads to various positions for the nondegenerate equilibrium between linkage isomers. Cyclic voltammetry and solvent-dependent charge transfer absorption spectra of the complexes reveal low-lying π^* levels which can become populated after chem. or electrochem. reduction, the spin distribution in the centrosym. binuclear complex of 1,5-naphthyridine anion radical was fully characterized using ESR and results from MO calculations In the experiment, the researchers used many compounds, for example, Pyrido[2,3-b]pyrazine (cas: 322-46-3HPLC of Formula: 322-46-3).

Pyrido[2,3-b]pyrazine (cas: 322-46-3) belongs to pyrazine derivatives. Pyrazines are volatile compounds that are used in the cosmetic, food, flavor, and fragrance industries. A large number of pyrazine derivatives are known for their antitumor, antibiotic, anticonvulsant, antituberculosis, and diuretic activities.HPLC of Formula: 322-46-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Whole-Molecule Calculation of Log P Based on Molar Volume, Hydrogen Bonds, and Simulated ¹³C NMR Spectra was written by Schnackenberg, Laura K.;Beger, Richard D.. And the article was included in Journal of Chemical Information and Modeling in 2005.Product Details of 6924-68-1 This article mentions the following:

The prediction of Log P is usually accomplished using either substructure or whole-mol. approaches. However, these methods are complicated, and previous whole-mol. approaches have not been successful for the prediction of Log P in very complex mols. The observed chem. shifts in NMR spectroscopy are related to the electrostatics at the nucleus, which are influenced by solute-solvent interactions. The different solvation effects on a mol. by either water or methanol have a strong effect on the NMR chem. shift value. Therefore, the chem. shift values observed in an aqueous and organic solvent should correlate to Log P. This paper develops a rapid, objective model of Log P based on molar volume, hydrogen bonds, and differences in calculated ¹³C NMR chem. shifts for a diverse set of compounds A partial least squares (PLS) model of Log P built on the sum of carbon chem. shift differences in water and methanol, molar volume, number of hydrogen bond donors and acceptors in 162 diverse compounds gave an r² value of 0.88. The average r² for 10 training models of Log P made from 90% of the data was 0.87±0.01. The average q² for 10 leave-10%-out cross-validation test sets was 0.87±0.05. In the experiment, the researchers used many compounds, for example, Ethyl pyrazine-2-carboxylate (cas: 6924-68-1Product Details of 6924-68-1).

Ethyl pyrazine-2-carboxylate (cas: 6924-68-1) belongs to pyrazine derivatives. Pyrazine has the elements of symmetry for the point group D2h. It has three mutually perpendicular two-fold axes. It also has three mutually perpendicular planes of symmetry. As a result, pyrazine also has a centre of symmetry. A number of pyrazine-based derivatives were used as dyes or fluorescent probes.Product Details of 6924-68-1

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem