• Journal of the Korean Chemical Society
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• v.43 no.3
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• pp.302-306
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• 1999

The 1,3-dipolar cycloaddition reaction of the quinoxaline 4-oxide 10 with 2-chloroacrylonitrile gave the 2,3-dihydro-lH-1,2-diazepino[3,4-blquinoxalines lla, b, respectively, which were converted into the 2,3,4,6-tetrahydro-lH-l,2-diazepino[3,4-b]quinoxaline 12. The reaction of compound lla with selenium dioxide in acetic acid/water resulted in ring transformation to give the 1,4-dihydro-4-oxopyridazino[3,4-blquinoxaline 13.

• Journal of the Korean Chemical Society
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• v.46 no.6
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• pp.581-584
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• 2002

• Korean Chemical Engineering Research
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• v.57 no.6
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• pp.847-852
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• 2019

In this study, the effect of additives on the performance of aqueous organic redox flow battery (AORFB) using quinoxaline and ferrocyanide as active materials in alkaline supporting electrolyte is investigated. Quinoxaline shows the lowest redox potential (-0.97 V) in KOH supporting electrolyte, while when quinoxaline and ferrocyanide are used as the target active materials, the cell voltage of this redox combination is 1.3 V. When the single cell tests of AORFBs using 0.1 M active materials in 1 M KCl supporting electrolyte and Nafion 117 membrane are implemented, it does not work properly because of the side reaction of quinoxaline. To reduce or prevent the side reaction of quinoxaline, the two types of additives are considered. They are the potassium sulfate as electrophile additive and potassium iodide as nucleophilie additive. Of them, when the single cell tests of AORFBs using potassium iodide as additive dissolved in quinoxaline solution are performed, the capacity loss rate is reduced to $0.21Ah{\cdot}L^{-1}per\;cycle$ and it is better than that of the single cell test of AORFB operated without additive ($0.29Ah{\cdot}L^{-1}per\;cycle$).

• Journal of the Korean Chemical Society
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• v.45 no.4
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• pp.325-333
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• 2001

The 4-substituted tetrazolo[1,5-a]quinoxalines were synthesized from 4-chlorotetrazolo-[1,5-a]quinoxaline(8) or 4-hydrazinotetrazolo[1,5-a]quinoxaline(9). Refluxing of the tetrazolo[1,5-a]quinoxaline(12) in N,N-dimethylformamide gave the 1,2,4-triazolo[3,4-c]tetrazolo[1,5-a]quinoxaline(13), which was also obtained by the reaction of compound 9 with ethyl chloroformate in N,N-dimethylformamide. The reaction of compound 9 with isothiocyanates in ethanol provided the tetrazolo[1,5-a]quinoxalines(14), whose reaction with dimethyl acetylenedicarboxylate afforded the tetrazolo[1,5-a]quinoxalines(15). The tetrazolo [1,5-a]quinoxalines(18) were obtained by the reaction of compound 9 with alkyl (ethoxymethylene)cyanoacetates. Some of the compounds showed antibacterial, antifungal or algicidal activities against some strains.

• Journal of the Korean Chemical Society
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• v.49 no.4
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• pp.363-369
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• 2005

• Journal of the Korean Chemical Society
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• v.48 no.4
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• pp.385-393
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• 2004

2-Ethoxycarbonyl-3-methylquinoxaline 1,4-dioxide (8) was synthesized from benzofuroxan and ethyl acetoacetate. The reaction of compound 8 with hydrazine hydrate or selenium dioxide gave 2-hydrazinocarbonyl-3-methylquinoxaline 1,4-dioxide (9) or 2-ethoxycarbonyl-3-formylquinoxaline 1,4-dioxide (10), respectively. The reaction of compound 9 with alkanoyl chlorides, benzoyl chlorides, heteroacyl chlorides, and benzenesulfonyl chlorides afforded 3-methyl-2-(substituted hydrazinocarbonyl)quinoxaline 1,4-dioxides (11-14), respectively. The reaction of compound 9 with sodium azide gave 2-azidocarbonyl-3-methylquinoxaline 1,4-dioxide (15), and then its refluxing in dioxane/alcohols resulted in the Curtius rearrangement to give N-(3-methyl-1,4-dioxoquinoxalin-2-yl)-alkyl carbamates (16). The reaction of compound 15 with substituted anilines afforded 2-(3-substituted phenylureido)-3-methylquinoxaline 1,4-dioxides (17). The reaction of compound 10 with benzoic hydrazide or substituted anilines provided quinoxaline 1,4-di-oxides (18, 19), respectively. The herbicidal and fungicidal activities of the synthesized compounds were investigated.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2581-2584
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• 2012

Hexafluoroisopropanol (HFIP) is explored as an effective medium for the synthesis of quinoxaline derivatives in high yields at room temperature. The solvent (HFIP) can be readily separated from reaction products and recovered in excellent purity for direct reuse.

• Journal of the Korean Chemical Society
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• v.55 no.2
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• pp.235-239
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• 2011

Fe/Al-MCM-41was found to be an effective catalyst for the synthesis of quinoxaline derivatives from the condensation of the 1,2-diamines and 1,2-dicarbonyl compounds in good yields. The catalyst is recyclable and reusable.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2005.05a
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• pp.85-86
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• 2005

• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2260-2266
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• 2011

4-Chlorotetrazolo[1,5-a]quinoxaline (III) was synthesized by azide (2+3) cycloaddition of 2,3-dichloroquinoxaline (II). Compound (III) on further refluxing with hydrazine hydrate furnished 4-hydrazinotetrazolo[1,5-a]quinoxaline (IV). Further refluxing of (IV) with different aromatic aldehydes in methanol yielded corresponding Schiff's bases V(a-j). Various 4-aminotetrazolo[1,5-a]quinoxaline based azetidinones VII(a-j) were synthesized by stirring the compounds V(a-j), at low temperature, with equimolar mixture of chloroacetylchloride & triethylamine in dry benzene, while 4-aminotetrazolo[1,5-a]quinoxaline based thiazolidinones VIII(a-j) were synthesized by refluxing Schiff's bases V(a-j) with thioglycolic acid in oil-bath. The structures of all the compounds were confirmed on the basis of $^1H$-NMR & FT-IR spectral data. All the newly synthesized compounds were screened for in-vitro antimicrobial activity against E. coli, S. aureus, K. pneumoniae & P. aeruginosa & antifungal activity against C. albicans. Few of them have exhibited the promising activity.