Pyrazines

Design, synthesis, and biological evaluation of novel tetramethylpyrazine derivatives as potential neuroprotective agents was written by Chen, Haiyun;Tan, Guolian;Cao, Jie;Zhang, Gaoxiao;Yi, Peng;Yu, Pei;Sun, Yewei;Zhang, Zaijun;Wang, Yuqiang. And the article was included in Chemical & Pharmaceutical Bulletin in 2017.Recommanded Product: 75907-74-3 This article mentions the following:

A series of tetramethylpyrazine (TMP) derivatives, e.g., I were designed, synthesized and investigated their abilities for scavenging free radicals and preventing against oxidative stress-induced neuronal damage in vitro. Among them, compound, I consisting of TMP, caffeic acid and a nitrone group, showed potent radical-scavenging activity. Compound, I had broad neuroprotective effects, including rescuing iodoacetic acid-induced neuronal loss and, preventing from tert-butylhydroperoxide (t-BHP)-induced neuronal injury. Compound, I exerted its neuroprotective effect against t-BHP injury via activation of the phosphatidyl inositol 3-kinase (P13K)/Akt signaling pathway. Furthermore, in a rat model of permanent middle cerebral artery occlusion, compound, e.g., I significantly improved neurol. deficits, and alleviated the infarct area and brain edema. Thus, the results suggest that compound I could be a potential neuroprotective agent for the treatment of neurol. disease, particularly ischemic stroke. In the experiment, the researchers used many compounds, for example, (3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3Recommanded Product: 75907-74-3).

(3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3) 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 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.Recommanded Product: 75907-74-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Solvent effects on NMR. Differential shifts of ring protons of heterocyclics in dimethyl sulfoxide was written by Rao, G. Venkoba;Balakrishnan, M.;Venkatasubramanian, N.. And the article was included in Indian Journal of Chemistry in 1975.HPLC of Formula: 6924-68-1 This article mentions the following:

The NMR spectra of pyrazine, pyridine, triazine, pyrrole, imidazole, Et furan-2-carboxylate, Me 4-pyridylacetate, and Et pyrazinecarboxylate are examined in (D3C)2SO. The differential shifts of ring protons are accounted for in terms of an interaction between the lone pair on the ring hetero atom and the pos. end of the sulfoxide dipole in the solvent. In the experiment, the researchers used many compounds, for example, Ethyl pyrazine-2-carboxylate (cas: 6924-68-1HPLC of Formula: 6924-68-1).

Ethyl pyrazine-2-carboxylate (cas: 6924-68-1) 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 undergo nearly all of the same reactions as pyrimidines, from nucleophilic substitution (SNAr) to palladium-catalyzed cross coupling reactions.HPLC of Formula: 6924-68-1

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthesis and characterization of dirhodium(II,II) formamidinate complexes containing short-bite nitrogen ligands was written by Tresoldi, Giuseppe;Lo Schiavo, Sandra;Nicolo, Francesco;Cardiano, Paola;Piraino, Pasquale. And the article was included in Inorganica Chimica Acta in 2003.Formula: C7H5N3 This article mentions the following:

The Rh⁴⁺₂ complex [Rh₂(form)₂(O₂CCF₃)₂(H₂O)₂] (form = N,N’-di-p-tolylformamidinate anion) easily reacts with the short-bite ligand pyrido[2,3-b]pyrazine, molar ratio 1:2, yielding [Rh₂(form)₂(pyrido[2,3-b]pyrazine)₂(O₂CCF₃)₂] which was characterized by conductivity measurements and IR and ¹H NMR spectroscopy. The complex exhibits a lantern type structure with the two N ligands coordinated, in a cisoid arrangement, at the equatorial positions across the dirhodium unit while the axial sites are occupied by two monoligated trifluoroacetate groups. Conductivity and IR data show that in DMSO the complex undergoes dissociation of both the axial ligands leading to [Rh₂(form)₂(pyrido[2,3-b]pyrazine)₂(DMSO)₂]²⁺. The parent compound reacts also with 2-chloro-5,7-dimethyl-1,8-naphthyridine and 2,7-dichloro-5-methyl-1,8-naphthyridine leading to [Rh₂(form)₂(O₂CCF₃)(C₁₀H₉N₂O)(H₂O)] and [Rh₂(form)₂(O₂CCF₃)(C₉H₆N₂ClO)(H₂O)], resp., in which the dirhodium unit is supported by three different bridging ligands. Microanal., ¹H NMR and x-ray data unambiguously show that the reaction proceeds, unexpectedly, with elimination of a trifluoroacetate group and the substitution of a Cl atom of the naphthyridine ligands by O. In the experiment, the researchers used many compounds, for example, Pyrido[2,3-b]pyrazine (cas: 322-46-3Formula: C7H5N3).

Pyrido[2,3-b]pyrazine (cas: 322-46-3) 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 large number of pyrazine derivatives are known for their antitumor, antibiotic, anticonvulsant, antituberculosis, and diuretic activities.Formula: C7H5N3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Proton, carbon-13, and nitrogen-15 nuclear magnetic resonance and CNDO/2 studies on the tautomerism and conformation of amiloride, a novel acylguanidine was written by Smith, Robert L.;Cochran, David W.;Gund, Peter;Cragoe, Edward J. Jr.. And the article was included in Journal of the American Chemical Society in 1979.COA of Formula: C6H7ClN4O2 This article mentions the following:

The favored ground-state structures were determined for the novel acylguanidine diuretic, amiloride (I), and its free base using natural-abundance ¹H, ¹³C, and ¹⁵N NMR techniques and CNDO/2 theor. calculations I existed primarily in the acylamino tautomer form as planar conformer F1, whereas the free base preferred the acylimino tautomer form as planar conformer A1 (and/or A4). The dynamic mechanism(s) for the exptl. observed rapid equilibrium of the terminal amino groups in I and the free base and, when N-substituted, their substituents were explored by the CNDO/2 method. Of the six possible pathways considered for effecting N-10-N-11 interconversion in the free base a novel mechanism involving a synchronous rotation around ϕ₂ and ϕ₃ was calculated to have the lowest barrier to interconversion. Exptl. verification of this novel mechanism was attempted, but not found, by preparation of an appropriate model, II and subsequent determination of the ΔG^ values (14.7-14.8 kcal/mol) for II and pyrazine analogs using the dynamic ¹³C NMR technique in Me₂SO-d₆-CD₃OI). The free base is likely to undergo N-10-N-11 interconversion via simple ϕ₃ rotation and/or ϕ₂ rotation plus inversion. Accordingly, I must equilibrate by a ϕ₃ rotation mechanism. In the experiment, the researchers used many compounds, for example, Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate (cas: 1458-01-1COA of Formula: C6H7ClN4O2).

Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate (cas: 1458-01-1) belongs to pyrazine derivatives. Pyrazine derivatives have antitumor, antibiotic, anticonvulsant, antituberculous and diuretic effects as well as kinase, enzymatic and potent tubulin and FtsZ polymerization inhibitory activities. 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.COA of Formula: C6H7ClN4O2

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthesis of tetramethylpyrazine derivatives by Mitsunobu reaction was written by Wang, Hui-ying;Sun, Ping-hua;Chen, Wei-min. And the article was included in Hecheng Huaxue in 2011.Application of 75907-74-3 This article mentions the following:

Three tetramethylpyrazine derivatives I(R = H, MeO), and II in yields of 87%∼92% were synthesized by Mitsunobu reaction from tetramethylpyrazine. The structures were characterized by ¹H NMR, ¹³C NMR and ESI-MS. In the experiment, the researchers used many compounds, for example, (3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3Application of 75907-74-3).

(3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3) 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. 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.Application of 75907-74-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Research of metabolic kinetics and reaction phenotyping of ligustrazin by using liver microsomes and recombinant human enzymes was written by Tan, Yan;Zhuang, Xiao-mei;Shen, Guo-lin;Li, Hua;Gao, Yue. And the article was included in Yaoxue Xuebao in 2014.Synthetic Route of C8H12N2O This article mentions the following:

The metabolic characteristics of ligustrazin (TMPz) in liver microsomes were studied. The reaction phenotyping of TMPz metabolism was also identified by in vitro assessment using recombinant human cytochrome P 450 enzymes (CYP) and UDP glucuronosyltransferases (UGT). TMPz was incubated at 37°C with human (HLM) and rat liver microsomes (RLM) in the presence of different co-factors. The metabolic stability and enzyme kinetics of TMPz were studied by determining its remaining concentrations with a LC-MS/MS method. TMPz was only metabolically eliminated in the microsomes with NADPH or NADPH+UDPGA. In the HLM and RLM with NADPH+UDPGA, t_1/2, K_m, and V_max of TMPz were 94.24±4.53 and 105.07±9.44 min, 22.74±1.89 and 33.09±2.74μmol·L^-1, 253.50±10.06 and 190.40±8.35 nmol·min^-1·mg^-1 (protein), resp. TMPz showed a slightly higher metabolic rate in HLM than that in RLM. Its primary oxidative metabolites, 2-hydroxymethyl-3,5,6-trimethylpyrazine (HTMP), could undergo glucuronide conjugation. The CYP reaction phenotyping of TMPz metabolism was identified using a panel of recombinant CYP isoforms (rCYP) and specific CYP inhibitors in HLM. CYP1A2, 2C9, and 3A4 were the major CYP isoforms involved in TMPz metabolism Their individual contributions were assessed by using the method of the total normalized rate to be 19.32, 27.79, and 52.90%, resp. It was observed that these CYP isoforms mediated the formation of HTMP in rCYP incubation. The UGT reaction phenotyping of HTMP glucuronidation was also studied preliminarily by using a panel of 6 UGT isoforms (rUGT). UGT1A1, 1A4, and 1A6 were the predominant isoforms mediated the HTMP glucuronidation. The results above indicated that the metabolism of TMPz involves multiple enzymes mediated phase I and phase II reactions. In the experiment, the researchers used many compounds, for example, (3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3Synthetic Route of C8H12N2O).

(3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3) 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. Substituted pyrazines have been found as subunits of multiple synthetically constructed therapeutic agents, as well as several natural products.Synthetic Route of C8H12N2O

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Structural determinants for AMPA agonist activity of aryl or heteroaryl substituted AMPA analogues. Synthesis and pharmacology was written by Sorensen, Ulrik S.;Falch, Erik;Stensbol, Tine B.;Jaroszewski, Jerzy W.;Madsen, Ulf;Krogsgaard-Larsen, Povl. And the article was included in Archiv der Pharmazie (Weinheim, Germany) in 2001.Reference of 6924-68-1 This article mentions the following:

We have previously reported the synthesis and pharmacol. characterization of analogs of 2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl)propionic acid (AMPA) in which the Me group was replaced by a Ph group (APPA) or heteroaryl groups. While 2-amino-3-[3-hydroxy-5-(2-furyl)-4-isoxazolyl]propionic acid and its 3-pyridyl analog 2-amino-3-[3-hydroxy-5-(3-pyridyl)-4-isoxazolyl]propionic acid (3-Py-AMPA) show very low affinity for AMPA receptors, introduction of heteroaryl substituents containing heteroatom in the 2-position provides potent AMPA receptor agonists. We here report the synthesis and pharmacol. of 2-amino-3-(3-hydroxy-5-pyrazinyl-4-isoxazolyl)propionic acid (IC₅₀ = 1.2 μM; EC₅₀ = 11 μM), which is weaker as an AMPA agonist than AMPA (IC₅₀ = 0.040 μM; EC₅₀ = 3.5 μM) but comparable in potency with 2-amino-3-[3-hydroxy-5-(2-pyridyl)-4-isoxazolyl]propionic acid (IC₅₀ = 0.57 μM; EC₅₀ = 7.4 μM), as determined in radioligand binding and electrophysiol. experiments, resp. The AMPA analogs containing 2-, 3-, or 4-methoxyphenyl substituents, resp., and the corresponding hydroxyphenyl analogs were also synthesized and evaluated pharmacol. With the exception of 2-amino-3-[3-hydroxy-5-(2-hydroxyphenyl)-4-isoxazolyl]propionic acid, which is a very weak AMPA agonist (IC₅₀ = 45 μM; EC₅₀ = 324 μM), none of these compounds showed detectable effect at AMPA receptors. In the experiment, the researchers used many compounds, for example, Ethyl pyrazine-2-carboxylate (cas: 6924-68-1Reference of 6924-68-1).

Ethyl pyrazine-2-carboxylate (cas: 6924-68-1) 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.Reference of 6924-68-1

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

A Specific Blend of Drakolide and Hydroxymethylpyrazines: An Unusual Pollinator Sexual Attractant Used by the Endangered Orchid Drakaea micrantha was written by Bohman, Bjoern;Tan, Monica M. Y.;Phillips, Ryan D.;Scaffidi, Adrian;Sobolev, Alexandre N.;Moggach, Stephen A.;Flematti, Gavin R.;Peakall, Rod. And the article was included in Angewandte Chemie, International Edition in 2020.COA of Formula: C8H12N2O This article mentions the following:

Bioactive natural products underpin the intriguing pollination strategy used by sexually deceptive orchids. These compounds, which mimic the sex pheromones of the female insect, are emitted in particular blends to lure male insect pollinators of specific species. By combining methods from field biol., anal. chem., electrophysiol., crystallog., and organic synthesis, we report that an undescribed β-hydroxylactone, in combination with two specific hydroxymethylpyrazines, act as pollinator attractants in the rare hammer orchid Drakaea micrantha. This discovery represents an unusual case of chem. unrelated compounds being used together as a sexual attractant. Furthermore, this is the first example of the identification of pollinator attractants in an endangered orchid, enabling the use of chem. in orchid conservation. Our synthetic blend is now available to be used in pollinator surveys to locate suitable sites for plant conservation translocations. In the experiment, the researchers used many compounds, for example, (3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3COA of Formula: C8H12N2O).

(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, α-hydroxyketone, α-methyl ketone. 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.COA of Formula: C8H12N2O

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Red-Light-Emitting System Based on Aggregation of Donor-Acceptor Derivatives in Polar Aqueous Media was written by Ishi-i, Tsutomu;Ikeda, Kei;Kichise, Yuki;Ogawa, Michiaki. And the article was included in Chemistry – An Asian Journal in 2012.Reference of 148231-12-3 This article mentions the following:

The authors have demonstrated that an efficient red-light-emitting system can be created in polar water media based on the aggregation of donor-acceptor dyes triphenylamine benzothiadiazole, triphenylamine benzoselenodiazole, and triphenylamine quinoxaline aggregates. The UV/Vis absorption and fluorescence spectra of the dyes were measured in a THF/water mixture, in which the concentration was kept at 1 × 10^-5 M and only the water fraction (volume%) was changed from 0% to 90%. The aggregation leads to the restriction of the solvation-induced nonradiative deactivation to recover and enhance the emission. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3Reference of 148231-12-3).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazine is an N-heterocyclic moiety, and it can be easily prepared from ethylenediamine and 1,2-diketone, α-hydroxyketone, α-methyl ketone. A number of pyrazine-based derivatives were used as dyes or fluorescent probes.Reference of 148231-12-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthesis, Properties, and Reactivity of Bis-BN Phenanthrenes: Stepwise Bromination of the Main Scaffold was written by Zi, Lingjian;Zhang, Jinyun;Li, Chenglong;Qu, Yi;Zhen, Bin;Liu, Xuguang;Zhang, Lei. And the article was included in Organic Letters in 2020.Electric Literature of C8H4Br2N2 This article mentions the following:

Two bis-BN phenanthrenes I (7, R² = H; 8, R²-R² = CH₂CH₂) have been synthesized. Their photophys. properties are different from those of the reported mono-BN phenanthrenes. Moreover, the stepwise bromination of bis-BN phenanthrene 8 gave a series of brominated bis-BN phenanthrenes, with all of the mono-, di-, tri-, and tetrabrominated bis-BN phenanthrenes being successfully isolated and characterized. In addition, preliminary results showed that mono- and dibrominated species can be further functionalized by cross-coupling reactions. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3Electric Literature of C8H4Br2N2).

5,8-Dibromoquinoxaline (cas: 148231-12-3) 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). Pyrazines are chemical compounds (technically called “methoxypyrazines”) found in grape skin and stems that are responsible for many “green” flavors in wine. Levels of pyrazines are dependent on viticultural practices, climate, and grape variety.Electric Literature of C8H4Br2N2

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem