Results 251 to 260 of about 14,380 (267)
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Tetrahedron, 1964
Abstract Base catalysed intramolecular cyclization of α-cyano- o -nitroacetanilides (Ia–d) to the corresponding 2-cyano-3-hydroxyquinoxaline 1-oxides (IIa-d) is described, and a mechanism proposed. The cyanoquinoxaline N-oxides (IIa-d) on reduction are deoxygenated with simultaneous loss of the nitrile group, and when heated with concentrated aqueous
M. S. Habib, Yusuf Ahmad, Ziauddin
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Abstract Base catalysed intramolecular cyclization of α-cyano- o -nitroacetanilides (Ia–d) to the corresponding 2-cyano-3-hydroxyquinoxaline 1-oxides (IIa-d) is described, and a mechanism proposed. The cyanoquinoxaline N-oxides (IIa-d) on reduction are deoxygenated with simultaneous loss of the nitrile group, and when heated with concentrated aqueous
M. S. Habib, Yusuf Ahmad, Ziauddin
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Journal of Polymer Science Part A-1: Polymer Chemistry, 1972
AbstractA series of new amide–quinoxaline ordered copolymers derived from phthaloyl, isophthaloyl, and terephthaloyl chlorides have been synthesized and characterized. The isophthaloyl and terephthaloyl polymers had decomposition temperatures between 445–495°C and were soluble in a variety of solvents. These high molecular weight polymers were prepared
James V. Duffy, Joseph M. Augl
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AbstractA series of new amide–quinoxaline ordered copolymers derived from phthaloyl, isophthaloyl, and terephthaloyl chlorides have been synthesized and characterized. The isophthaloyl and terephthaloyl polymers had decomposition temperatures between 445–495°C and were soluble in a variety of solvents. These high molecular weight polymers were prepared
James V. Duffy, Joseph M. Augl
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Quinoxalines as analytical reagents
Analytica Chimica Acta, 1967Abstract 2,3-Bis(2-pyridyl)quinoxaline and 25 substituted derivatives were prepared and assessed as spectrophotometric reagents for copper The compounds contain the copper(I)-specific “cuproine” grouping, but are much more readily prepared than most cuproine-type reagents The possible formulations of the copper(I) chelates present under various ...
W.I. Stephen, P.C. Uden
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Crosslinked polyamide‐quinoxalines
Journal of Polymer Science: Polymer Letters Edition, 1973O, S, SO OR SO2 AND Y IS O-PHENYLENE, M-PHENYLENE, P-PHENYLENE OR- 1,2-DI(NH2-),4-((3,4-DI(NH2-)PHENYL)-X-)BENZENE WITH AN AMIDE OF THE FORMULA 1,3-BIS(PHENYL-CO-CO-Y-NH-CO-),5-(R-OOC-)BENZENE THESE POLYMERS FIND USE AS FILM OR COATINGS AND CAN ALSO BE MADE INTO FIBERS.
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Quinoxaline derivatives of severalalkaloids
Chemistry of Natural Compounds, 2010New quinoxaline derivatives were prepared by reaction of 2-quinoxalinehydroximoylbromide with the alkaloids anabasine, cytisine, and salsoline.
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Quinoxaline–As a Parent Heterocycle
2016Quinoxalines are products of the spontaneous condensation of 1,2-diaminobenzene (1,2-DAB) with 1,2-dicarbonyl compounds.
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Synthesis of Quinoxaline Macrocycles
2016Macrocyclic compounds are widespread in nature. These are porphyrins (chlorophyll, heme as a part of hemoglobin, Vitamin B12), cyclic peptides (antibiotics gramicidin C, capreomycin, valinomycin, vancomycin, amato, and fallotokcins of death cup amanita (Amanita phalloides) and some toadstools), macrocyclic alkaloids (including tubocurarin–the main ...
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On the Reduction of Quinoxaline
The Journal of Organic Chemistry, 1963R. E. Holliday, Jan Hamer
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