- Chemoselective synthesis of 3,6,7-trisubstituted 2-(2,3:5,6-di-O-isopropylidene-β-D-mannofuranosyloxy]- and 2-(2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-β-D-glucopyranosyloxy)quinoxaline derivatives
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[Figure not available: see fulltext.] A series of quinoxaline O-nucleosides, 3,6,7-trisubstituted 2-(2,3:5,6-di-O-isopropylidene-β-D-mannofuranosyl-1-yl)quinoxalines and 2-(2-acetamido-2-deoxy-3,4,6-tri-O-acetyl-β-D-glucopyranosyl)quinoxalines, was prepared by the reaction of 3,6,7-trisubstituted quinoxalin-2(1H)-ones with the corresponding protected α-chlorosugars in the presence of NaH. The reaction proceeded chemoselectively to give products of O-substitution with β-configuration at anomeric carbon, as proved by NMR data. The deprotection of the 1-(2-acetamido-2-deoxy-3,4,6-tri-O-acetyl-β-D-glucopyranosyl)quinoxalines was achieved by stirring in ammonia-methanol mixture to afford free O-quinoxaline nucleoside analogs.
- Fathalla, Walid
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- [Ir(P-OP)]-catalyzed asymmetric hydrogenation of diversely substituted C=N-containing heterocycles
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Iridium(I) complexes of enantiomerically pure phosphine-phosphite ligands ([Ir(Cl)(cod)(P - OP)]) efficiently catalyze the enantioselective hydrogenation of diverse C=N-containing heterocyclic compounds (benzoxazines, benzoxazinones, benzothiazinones, and quinoxalinones; 25 examples, up to 99% ee). A substrate-to-catalyst ratio as high as 2000:1 was reached.
- Nunez-Rico, Jose Luis,Vidal-Ferran, Anton
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supporting information
p. 2066 - 2069
(2013/06/04)
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- Citric acid: An efficient and green catalyst for rapid one pot synthesis of quinoxaline derivatives at room temperature
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The condensation of o-phenylenediamines with 1,2-dicarbonyl compounds in the presence of citric acid afforded the corresponding quinoxaline derivatives in higher yields at room temperature in ethanol, and most of the reactions were completed in less than 1 min.
- Mahesh, Radhakrishnan,Dhar, Arghya Kusum,Sasank T.v.n.v., Tara,Thirunavukkarasu, Sappanimuthu,Devadoss, Thangaraj
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experimental part
p. 389 - 392
(2012/01/05)
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- Synthesis of substituted 1,3-dimethyl-1H-quinoxalin-2-ones from aniline derivatives
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Substituted 1,3-dimethyl-1H-quinoxalin-2-ones (7) have been synthesized through the procedures of acylation, nitration, reduction, intramolecular alkylation, oxidation, and N-methylation starting from 3,4-disubstituted aniline.
- Li, Xun,Wang, Donghua,Wu, Jifeng,Xu, Wenfang
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p. 2741 - 2751
(2007/10/03)
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- Novel approach to 3-methyl-1H-quinoxalin-2-ones
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A novel approach to the synthesis of 3-methyl-1H-quinoxalin-2-ones has been described. These compounds were regioselectively prepared by starting from substituted phenylamines and α-chloropropionyl chloride through the efficient procedures of acylation, nitration, reduction, intramolecular alkylation, and oxidation. Copyright Taylor & Francis, Inc.
- Li, Xun,Wang, Donghua,Wu, Jifeng,Xu, Wenfang
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p. 2553 - 2560
(2007/10/03)
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- Quinoxalinone compounds useful for expanding the lumina or air passages in mammals
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Compounds of the formula below are useful for expanding the lumina or air passages in a mammal in need of said treatment. The compounds are also useful for treating atopic eczema and urticaria. STR1 wherein X and Y are the same or different and are hydrogen, fluoro, chloro, bromo, nitro, trifluoromethyl, alkyl of one to four carbon atoms, inclusive, alkoxy of one to four carbon atoms, inclusive, and cyano; R1 is hydrogen, methyl or ethyl; R2 is hydrogen, alkyl of one to six carbon atoms, inclusive, phenyl, benzyl, CH2 Z wherein Z is fluoro, chloro, or bromo, CO2 M, CH2 CO2 M, CH2 CH2 CO2 M and CHR3 CO2 M wherein M is hydrogen, alkyl of one to four carbon atoms, inclusive, or a physiologically acceptable metal or amine cation and R3 is alkyl of one to three carbon atoms, inclusive, with the proviso that M is not hydrogen when R2 is CH2 CO2 M or a CHR3 CO2 M.
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