Heterocyclic Building Blocks-quinoxaline

Scope of tetrazolo[1,5-a]quinoxalines in CuAAC reactions for the synthesis of triazoloquinoxalines, imidazoloquinoxalines, and rhenium complexes thereof was written by Holzhauer, Laura;Liagre, Chloe;Fuhr, Olaf;Jung, Nicole;Braese, Stefan. And the article was included in Beilstein Journal of Organic Chemistry in 2022.Quality Control of Quinoxalin-2-amine This article mentions the following:

The conversion of tetrazolo[1,5-a]quinoxalines I (R = H, i-Pr, Ph, etc.) to 1,2,3-triazoloquinoxalines II (R¹ = n-Bu, Ph, 1,3-dioxo-isoindolinylmethyl, etc.) and triazoloimidazoquinoxalines III (R¹ = Ph, n-Bu)under typical conditions of a CuAAC reaction has been investigated. Derivatives of the novel compound class of triazoloimidazoquinoxalines (TIQ) and rhenium(I) triazoloquinoxaline complexes IV and [N,N-diethyl-2-(1-(quinoxalin-2-yl)-1H-1,2,3-triazol-4-yl)ethan-1-amine]bromotricarbonylrhenium(I) as well as a new TIQ rhenium complex such as [1-butyl-4-(4-butyl-1H-1,2,3-triazol-1-yl)imidazo[1,2-a]quinoxaline]bromotricarbonylrhenium(I) were synthesized. As a result, a small 1,2,3-triazoloquinoxaline library was obtained and the method could be expanded towards 4-substituted tetrazoloquinoxalines. The compatibility of various aliphatic and aromatic alkynes R¹CCH towards the reaction was investigated and the denitrogenative annulation towards imidazoloquinoxalines V could be observed as a competing reaction depending on the alkyne concentration and the substitutions at the quinoxaline. In the experiment, the researchers used many compounds, for example, Quinoxalin-2-amine (cas: 5424-05-5Quality Control of Quinoxalin-2-amine).

Quinoxalin-2-amine (cas: 5424-05-5) belongs to quinoxaline derivatives. Compounds possessing quinoxaline derivatives were bestowed with a variety of significant biological properties such as antiviral, antimalarial, anticancer, DNA intercalation, DNA duplex stabilization, and many others. Modifying quinoxaline structure it is possible to obtain a wide variety of biomedical applications, namely antimicrobial activities and chronic and metabolic diseases treatment.Quality Control of Quinoxalin-2-amine

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Single quad mass analyzer coupled UPLC method for impurity profile of Brimonidine tartrate and Timolol maleate: Application in their binary mixture ophthalmic formulation was written by Kondra, S.;Akula Thukaram, B.;Gowrisankar, D.;Krishnamanjari, P. A.;Raju Dantuluri, H. S. N.;Maganti, S.. And the article was included in Annales Pharmaceutiques Francaises in 2021.Reference of 70359-46-5 This article mentions the following:

The main objective of the study is to develop a suitable and rapid UPLC/PDA method by coupling online to Quadrupole Dalton analyzer (QDa), a mass detector for the identification and impurity profiling of Brimonidine Tartrate (BRIM)/Timolol maleate (TIMO) in the ophthalmic formulation. Chromatog. separation was achieved on ethylene bridged hybrid octadecylsilane column having 1.7m particle size in gradient mode using high pure heptafluorobutyric acid as a buffer (A) and water, methanol, and acetonitrile (B) as mobile phase with a flow rate of 0.3 mL min^-1. Based on the spectral maxima, BRIM and its impurities were monitored at 248 nm, and TIMO and its impurities were monitored at 295 nm. During evaluation of stress conditions and stability data unknown degradants are observed and identified as m/z 218.01 (DP1) and m/z 390.03 (DP2) using QDa-ESI+ scanning mode technique. The performance of the method was systematically validated according to ICH Q2 (R1) guidelines and the method shown very good sensitivity (≥ 0.5g. mL^-1) and linearity (r² ≥ 0.999) with consistent recoveries and less than 5% RSD for all compounds Hence, the proposed UPLC/PDA/QDa method is a simple, sensitive and comprehensive technique where identification and quantification can be done. It gives for complete impurity profile evaluation of BRIM/TIMO in the ophthalmic formulation during quality control in the pharmaceutical industry. In the experiment, the researchers used many compounds, for example, 5-Bromo-N-(4,5-dihydro-1H-imidazol-2-yl)quinoxalin-6-amine (2R,3R)-2,3-dihydroxysuccinate (cas: 70359-46-5Reference of 70359-46-5).

5-Bromo-N-(4,5-dihydro-1H-imidazol-2-yl)quinoxalin-6-amine (2R,3R)-2,3-dihydroxysuccinate (cas: 70359-46-5) belongs to quinoxaline derivatives. Quinoxalines have received a significant amount of attention due to their potential use in fighting various pathophysiological conditions like epilepsy, Parkinson’s, and Alzheimer’s diseases. The antitumoral properties of quinoxaline compounds have been of interest. Recently, quinoxaline and its analogs have been investigated as the catalyst’s ligands.Reference of 70359-46-5

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Regulating Photophysical Property of Aggregation-Induced Delayed Fluorescence Luminogens via Heavy Atom Effect to Achieve Efficient Organic Light-Emitting Diodes was written by Xu, Jingwen;Wu, Xing;Li, Jinshi;Zhao, Zujin;Tang, Ben Zhong. And the article was included in Advanced Optical Materials in 2022.Application In Synthesis of Dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile This article mentions the following:

Heavy atom effect is beneficial to delayed fluorescence by enlarging spin-orbit coupling (SOC). The introduction of halogen atoms to luminogenic mols. is a widely used approach to realize heavy atom effect, but the positions of halogen atoms may exert quite different impacts on the photophys. properties of the mols. To confirm this hypothesis, herein, bromine atoms are introduced on a delayed fluorescence luminogen comprised of benzoyl acceptor and phenoxazine and phenylcarbazole donors at different positions. The resultant luminogens show great differences in photoluminescence (PL) efficiencies and delayed fluorescence lifetimes in solid state, which could be attributed to different orbital contribution ratios of bromine atoms to mol. frontier orbitals and thus varied SOC interactions, as revealed by spectroscopy, crystallog., and theor. calculation The luminogens with bromine atoms on the phenylcarbazole units hold much better PL properties than those with bromine atoms on other positions, and behave efficiently as emitters in organic light-emitting diodes, furnishing high external quantum efficiencies of up to 28.6% and small efficiency roll-offs. The structure-property relationship gained in this work can provide guidance for the further design of efficient luminescent materials. In the experiment, the researchers used many compounds, for example, Dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (cas: 105598-27-4Application In Synthesis of Dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile).

Dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (cas: 105598-27-4) belongs to quinoxaline derivatives. Compounds possessing quinoxaline derivatives were bestowed with a variety of significant biological properties such as antiviral, antimalarial, anticancer, DNA intercalation, DNA duplex stabilization, and many others. The parent substance of the group, quinoxaline, results when glyoxal is condensed with 1,2-diaminobenzene. Substituted derivatives arise when α-ketonic acids, α-chlorketones, α-aldehyde alcohols and α-ketone alcohols are used in place of diketones.Application In Synthesis of Dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Highly Efficient Deep-Blue Phosphorescent OLEDs Based on a Trimethylsilyl-Substituted Tetradentate Pt(II) Complex was written by Park, Hea Jung;Jang, Jee-Hun;Lee, Jeong-Hwan;Hwang, Do-Hoon. And the article was included in ACS Applied Materials & Interfaces in 2022.HPLC of Formula: 105598-27-4 This article mentions the following:

Compared to Ir(III) complexes with octahedral geometries, Pt(II) complexes with square planar geometries show superior optical properties because their flat shapes lead to an orientation that enhances the outcoupling of organic light-emitting diodes (OLEDs). However, the flat shapes of Pt(II) complexes typically induce a bathochromic shift, limiting their application in high-performance deep-blue phosphorescent OLEDs with high color purity. In this study, bulky trimethylsilyl (TMS)-substituted blue phosphorescent Pt(II) complex (PtON7-TMS) is successfully synthesized to improve color purity. The TMS substituent containing Si atom effectively suppresses intermol. interaction and aggregation even when the complex concentration in the film state is higher than 30 wt %. As a result, the PtON7-TMS-based OLEDs exhibit a maximum external quantum efficiency of 21.4%, along with a pure-blue color of CIE (0.14, 0.09) at 20 wt % doping concentration and a full-width at half maximum of 30 nm. The pure blue color is maintained at a higher doping concentration (>30 wt %). In the experiment, the researchers used many compounds, for example, Dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (cas: 105598-27-4HPLC of Formula: 105598-27-4).

Dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (cas: 105598-27-4) belongs to quinoxaline derivatives. Compounds possessing quinoxaline derivatives were bestowed with a variety of significant biological properties such as antiviral, antimalarial, anticancer, DNA intercalation, DNA duplex stabilization, and many others. Quinoxalines are used in the treatment of bacterial, cancer, and HIV infections. Moreover, varenicline, a clinical drug is used for treating nicotine addiction, also contains quinoxaline moiety.HPLC of Formula: 105598-27-4

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Effects of inhibiting antioxidant pathways on cellular hydrogen sulfide and polysulfide metabolism was written by Olson, Kenneth R.;Gao, Yan. And the article was included in Free Radical Biology & Medicine in 2019.Computed Properties of C10H8Br2N2O2 This article mentions the following:

Elaborate antioxidant pathways have evolved to minimize the threat of excessive reactive oxygen species (ROS) and to regulate ROS as signaling entities. ROS are chem. and functionally similar to reactive sulfur species (RSS) and both ROS and RSS have been shown to be metabolized by the antioxidant enzymes, superoxide dismutase and catalase. Here we use fluorophores to examine the effects of a variety of inhibitors of antioxidant pathways on metabolism of two important RSS, hydrogen sulfide (H₂S with AzMC) and polysulfides (H₂S_n, where n = 2-7, with SSP4) in HEK293 cells. Cells were exposed to inhibitors for up to 5 days in normoxia (21% O₂) and hypoxia (5% O₂), conditions also known to affect ROS production Decreasing intracellular glutathione (GSH) with L-buthionine-sulfoximine (BSO) or di-Et maleate (DEM) decreased H₂S production for 5 days but did not affect H₂S_n. The glutathione reductase inhibitor, auranofin, initially decreased H₂S and H₂S_n but after two days H₂S_n increased over controls. Inhibition of peroxiredoxins with conoidin A decreased H₂S and increased H₂S_n, whereas the glutathione peroxidase inhibitor, tiopronin, increased H₂S. Aminoadipic acid, an inhibitor of cystine uptake did not affect either H₂S or H₂S_n. In buffer, the glutathione reductase and thioredoxin reductase inhibitor, 2-AAPA, the glutathione peroxidase mimetic, ebselen, and tiopronin variously reacted directly with AzMC and SSP4, reacted with H₂S and H₂S₂, or optically interfered with AzMC or SSP4 fluorescence. Collectively these results show that antioxidant inhibitors, generally known for their ability to increase cellular ROS, have various effects on cellular RSS. These findings suggest that the inhibitors may affect cellular sulfur metabolism pathways that are not related to ROS production and in some instances they may directly affect RSS or the methods used to measure them. They also illustrate the importance of carefully evaluating RSS metabolism when biol. or pharmacol. attempting to manipulate ROS. In the experiment, the researchers used many compounds, for example, 2,3-Bis(bromomethyl)quinoxaline 1,4-dioxide (cas: 18080-67-6Computed Properties of C10H8Br2N2O2).

2,3-Bis(bromomethyl)quinoxaline 1,4-dioxide (cas: 18080-67-6) belongs to quinoxaline derivatives. Compounds possessing quinoxaline derivatives were bestowed with a variety of significant biological properties such as antiviral, antimalarial, anticancer, DNA intercalation, DNA duplex stabilization, and many others. Quinoxaline-1,4-di-N-oxide derivatives have shown to improve the biological results and are endowed with anti-viral, anti-cancer, anti-bacterial, and anti-protozoal activities with application in many other therapeutic areas.Computed Properties of C10H8Br2N2O2

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Metabolomic profitling of aqueous humor and plasma in primary open angle glaucoma patients points towards novel diagnostic and therapeutic strategy was written by Tang, Yizhen;Pan, Yiqiong;Chen, Yuhong;Kong, Xiangmei;Chen, Junyi;Zhang, Hengli;Tang, Guangxian;Wu, Jihong;Sun, Xinghuai. And the article was included in Frontiers in Pharmacology in 2021.Related Products of 70359-46-5 This article mentions the following:

Glaucoma is the second leading cause of blindness globally characterized by progressive loss of retinal ganglion cells (RGCs) and irreversible visual deficiency. As the most common type of glaucoma, primary open angle glaucoma (POAG) is currently an unmet medical need with limited therapy by lowering intraocular pressure (IOP). However, some patients continue to progress even though their IOP are controlled. Although early diagnosis and prompt treatment are crucial in preventing irreversible visual impairment, there are currently no biomarkers for screening POAG. Metabolomics has the advantages of illustrating the final downstream products of the genome and establishing the closest link to the phenotype. So far, there is no study investigating the metabolomic profiles in both aqueous humor and plasma of POAG patients. Therefore, to explore diagnostic biomarkers, unveil underlying pathophysiol. and potential therapeutic strategies, a widely targeted metabolomic approach was applied using ultrahigh-resolution mass spectrometry with C18 liquid chromatog. to characterize the metabolomic profiles in both aqueous humor and plasma of 28 POAG patients and 25 controls in our study. Partial least squares-discriminant anal. (PLS-DA) was performed to determine differentially expressed metabolites (DEMs) between POAG and age-matched controls. The area under the receiver operating characteristic curve (AUC) was calculated to assess the prediction accuracy of the DEMs. The correlation of DEMs with the clin. parameters was determined by Pearson correlation, and the metabolic pathways were analyzed using MetaboAnalyst 4.0. PLS-DA significantly separated POAG from controls with 22 DEMs in the aqueous humor and 11 DEMs in the plasma. Addnl., univariate ROC anal. and correlation anal. with clin. parameters revealed cAMP (AUC = 0.87), 2- methylbenzoic acid (AUC = 0.75), 3-sialyllactose (AUC = 0.73) in the aqueous humor and N-lac-phe (AUC = 0.76) in the plasma as potential biomarkers for POAG. Moreover, the metabolic profiles pointed towards the alteration in the purine metabolism pathway. In conclusion, the study identified potential and novel biomarkers for POAG by crosslinking the metabolomic profiles in aqueous humor and plasma and correlating with the clin. parameters. These findings have important clin. implications given that no biomarkers are currently available for glaucoma in the clinic, and the study provided new insights in exploring diagnostic biomarkers and potential therapeutic strategies of POAG by targeting metabolic pathways. In the experiment, the researchers used many compounds, for example, 5-Bromo-N-(4,5-dihydro-1H-imidazol-2-yl)quinoxalin-6-amine (2R,3R)-2,3-dihydroxysuccinate (cas: 70359-46-5Related Products of 70359-46-5).

5-Bromo-N-(4,5-dihydro-1H-imidazol-2-yl)quinoxalin-6-amine (2R,3R)-2,3-dihydroxysuccinate (cas: 70359-46-5) belongs to quinoxaline derivatives. Quinoxalines are important class of heterocyclic compounds, associated with wider pharmacological applications. Quinoxalines are used as dyes, pharmaceuticals, and antibiotics such as echinomycin, levomycin exhibiting antitumoral properties. Quinoxalines establish also the basis of anthelmintics and receptor antagonists.Related Products of 70359-46-5

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Cleaning method development and validation of brimonidine tartrate residue from brimonidine tartrate API was written by Ali, Sayyad. Kousr;Mandal, Tanmoy. And the article was included in Analytical Chemistry: An Indian Journal in 2021.Electric Literature of C15H16BrN5O6 This article mentions the following:

To Develop the Precise, Linear and Accurate Cleaning method Validation for the Brimonidine Tartrate from Brimonide tartrate Active Pharmaceutical Ingredient as per International Conference on Harmonization guidelines by using High Performance Liquid Chromatog. In this method uses a reverse phase C18 column make as inert sustain AQ C18 column (250 x 4.6 mm, 5μ), mobile phase-a as 0.1% ortho phosphoric acid and mobile phase-b as acetonitrile : methanol (50:50) volume/volume, flow rate as 1.2 mL/min, and detection of wavelength AS 248 nm, column temperature 40°C, injection volume 10μL and autosampler temperature 25°C by using Photo Diode Array Detector. In this method Brimonidine tartrate peak was eluted at 3.9 min. Brimonidine tartrate linear range was 0.5μg/mL to7.5μg/mL. In System suitability the % Relative standard deviation observed as 0.5. In swab and Rinse samples recovery was found between 97% to 103%. The limit of Quantification and limit of Detection range is found to be 0.5μg/mL and 0.15μg/mL resp. An accurate, linear and precise Reverse phase High Performance Liquid Chromatog. method was developed and validated as per International Conference on Harmonization guidelines. Hence this cleaning method validation is used for routine anal. of the residue samples in various pharmaceutical manufacturing areas. In the experiment, the researchers used many compounds, for example, 5-Bromo-N-(4,5-dihydro-1H-imidazol-2-yl)quinoxalin-6-amine (2R,3R)-2,3-dihydroxysuccinate (cas: 70359-46-5Electric Literature of C15H16BrN5O6).

5-Bromo-N-(4,5-dihydro-1H-imidazol-2-yl)quinoxalin-6-amine (2R,3R)-2,3-dihydroxysuccinate (cas: 70359-46-5) belongs to quinoxaline derivatives. Quinoxalines have received a significant amount of attention due to their potential use in fighting various pathophysiological conditions like epilepsy, Parkinson’s, and Alzheimer’s diseases. Quinoxalines are used in the treatment of bacterial, cancer, and HIV infections. Moreover, varenicline, a clinical drug is used for treating nicotine addiction, also contains quinoxaline moiety.Electric Literature of C15H16BrN5O6

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Hindered amines. Part 4. 3,3-Dialkyl-1,2,3,4-tetrahydro-2-quinoxalinones and cis- and trans-3,3-dialkyldecahydro-2-quinoxalinones was written by Lai, John T.. And the article was included in Synthesis in 1982.SDS of cas: 80636-30-2 This article mentions the following:

Tetrahydroquinoxalinones I [R = H; R¹ = Me, R² = Me, hexyl; R¹R² = (CH₂)₄, (CH₂)₅] were obtained by treating o-(H₂N)₂C₆H₄ with R¹R²CO and CHCl₃. I (R = 6-Me, 7-Me, 6-Cl, 7-Cl, R¹ = R² = Me) were obtained from 3,4-(H₂N)₂C₆H₃R and Cl₃CCMe₂OH. Rh-C hydrogenation of I (R = H) gave cis–II. trans–II were obtained from HOCR¹R²CN and 1,2-cyclohexanediamine. In the experiment, the researchers used many compounds, for example, 3,3-Dimethyl-3,4-dihydroquinoxalin-2(1H)-one (cas: 80636-30-2SDS of cas: 80636-30-2).

3,3-Dimethyl-3,4-dihydroquinoxalin-2(1H)-one (cas: 80636-30-2) belongs to quinoxaline derivatives. Quinoxaline derivatives are important constituents of pharmacologically active compounds, including antibacterial, antibiotic and antineoplastic, antifungal, anti-inflammatory and analgesic drugs. Quinoxaline and its analogues may also be formed by reduction of amino acids substituted 1,5-difluoro-2,4-dinitrobenzene (DFDNB),One study used 2-iodoxybenzoic acid (IBX) as a catalyst in the reaction of benzil with 1,2-diaminobenzene.SDS of cas: 80636-30-2

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Isolation and characterization of thermal degradation impurity in brimonidine tartrate by HPLC, LC-MS/MS, and 2DNMR was written by Baksam, Vijayakumar;Nimmakayala, Saritha;Devineni, Subba Rao;Muchumarri, Rama Mohan R.;Shandilya, Sanjeev;Kumar, Pramod. And the article was included in Journal of Pharmaceutical and Biomedical Analysis in 2021.Computed Properties of C15H16BrN5O6 This article mentions the following:

One potential unknown impurity was detected during the anal. of stability batches of brimonidine tartrate (BMT) in the level ranging from 0.03% to 0.06% by high-performance liquid chromatog. (HPLC). Based on the liquid chromatog.-mass spectrophotometry (LC-MS) anal., the unknown impurity structure was presumed as 3,6,11,13,16-pentaazatetracyclo [8.6.0.02,7.012,16] hexadeca-1,3,5,7,9,12-hexaene. The proposed structure was elucidated, after its isolation using preparative liquid chromatog. from the impurity enriched reaction crude sample, using anal. applications such as 1D NMR (1H, 13C and DEPT-135), 2D NMR (HMBC and COSY), high-resolution mass spectrometry (HRMS) and IR spectroscopy (IR). The unknown impurity was prepared from brimonidine by following Ullman coupling reaction in the presence of CuBr₂ in gram scale with optimum purity to use further in anal. developments. The identification, structural elucidation and synthesis of unknown degradation impurity such as BMT-cyclized impurity, and HPLC method validation were reported for the first time in this paper. In the experiment, the researchers used many compounds, for example, 5-Bromo-N-(4,5-dihydro-1H-imidazol-2-yl)quinoxalin-6-amine (2R,3R)-2,3-dihydroxysuccinate (cas: 70359-46-5Computed Properties of C15H16BrN5O6).

5-Bromo-N-(4,5-dihydro-1H-imidazol-2-yl)quinoxalin-6-amine (2R,3R)-2,3-dihydroxysuccinate (cas: 70359-46-5) belongs to quinoxaline derivatives. Compounds possessing quinoxaline derivatives were bestowed with a variety of significant biological properties such as antiviral, antimalarial, anticancer, DNA intercalation, DNA duplex stabilization, and many others. The parent substance of the group, quinoxaline, results when glyoxal is condensed with 1,2-diaminobenzene. Substituted derivatives arise when α-ketonic acids, α-chlorketones, α-aldehyde alcohols and α-ketone alcohols are used in place of diketones.Computed Properties of C15H16BrN5O6

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider

Highly efficient and concentration-insensitive OLEDs based on alkyl sterically modified red homoleptic phenylphthalazine iridium complexes was written by Tao, Zheng-Yu;Pan, Ze-Hui;Wang, Ying-Jie;Fu, Tian-Ling;Xu, Hui-Hui;Zhang, Qian-Feng;Tong, Bi-Hai;Fung, Man-Keung;Tian, Yong-Pan. And the article was included in Dyes and Pigments in 2022.Safety of Dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile This article mentions the following:

Four red homoleptic iridium (III) complexes (Ir1-Ir4) with steric phenylphthalazine ligands have been synthesized. Single X-ray structural anal. shows that the steric hindrance groups can prevent mol. aggregation. All complexes exhibited red emission with peaks between 614 and 629 nm in CH₂Cl₂ and photoluminescence quantum yields (QYs) of 44%-86% in doped films. They were concentration-insensitive, their QYs in neat powder and air atm. can reach a maximum of 15%. These complexes exhibited excellent thermal stability with T_d higher than 416 °C. The OLEDs based on these complexes showed good performances at 10 wt% high doping concentration Especially, the device based on Ir1 gave a peak current efficiency and external quantum efficiency (EQE) of 25.0 cd A^-1 and 24.2% with mild efficiency roll-off, which is the most efficient OLED based on phthalazine iridium complexes. The maximum EQEs of non-doped devices are between 4.0% and 5.6%, which are considerably high, compared with the reported efficiency of iridium complexes based red-emitting non-doped devices. These studies show that increasing the d. of the rigid steric groups of iridium complexes is very effective to achieve high efficiency and low concentration sensitive red phosphorescent devices. In the experiment, the researchers used many compounds, for example, Dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (cas: 105598-27-4Safety of Dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile).

Dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile (cas: 105598-27-4) belongs to quinoxaline derivatives. Quinoxalines have received a significant amount of attention due to their potential use in fighting various pathophysiological conditions like epilepsy, Parkinson’s, and Alzheimer’s diseases. Quinoxaline and its analogues may also be formed by reduction of amino acids substituted 1,5-difluoro-2,4-dinitrobenzene (DFDNB),One study used 2-iodoxybenzoic acid (IBX) as a catalyst in the reaction of benzil with 1,2-diaminobenzene.Safety of Dipyrazino[2,3-f:2′,3′-h]quinoxaline-2,3,6,7,10,11-hexacarbonitrile

Referemce:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider