Results 221 to 230 of about 14,696 (253)

Quinoxaline-Bridged Porphyrinoids

Journal of the American Chemical Society, 2002
Quinoxaline-bridged porphyrinoids (3), the first macrocycles containing dipyrrolylquinoxaline (DPQ, 1) subunits, were synthesized from the condensation of the diformyl-substituted DPQ derivatives (2) and 1,8-diaminoanthracene. The resulting structures were confirmed by X-ray analyses, which showed encapsulation of CHCl(3) molecules within the columnar ...
Jonathan L, Sessler, Hiromitsu, Maeda, Toshihisa, Mizuno, Vincent M, Lynch, Hiroyuki, Furuta   +4 more
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Structures of quinoxaline antibiotics

Acta Crystallographica Section B Structural Science, 1995
The crystal structures of three quinoxaline antibiotics-echinomycin 2QN, triostin C and the C222(1) form of triostin A--have been determined, and the structure of the P2(1)2(1)2(1) form of triostin A has been re-refined against our previously reported data. The molecular conformations are compared with those deduced from NMR data and those reported for
G M, Sheldrick, A, Heine, K, Schmidt-Bäse, E, Pohl, P G, Jones, E, Paulus, M J, Waring   +6 more
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Synthesis of fused quinoxalines

Mendeleev Communications, 2002
AbstractFor Abstract see ChemInform Abstract in Full Text.
Michail G. Ponizovsky, Artem M. Boguslavsky, Mikhail I. Kodess, Valery N. Charushin, Oleg N. Chupakhin   +4 more
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Pyrrolo[1,2-a]quinoxalines based on quinoxalines (Review)

Chemistry of Heterocyclic Compounds, 2010
Published data on methods for the synthesis of pyrrolo[1,2-a]quinoxalines, based on derivatives of quinoxalines and also on compounds that are not initially derivatives of quinoxalines or pyrroles are summarized and classified.
V. A. Mamedov, A. A. Kalinin
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Alkynyl- and dialkynyl-quinoxalines. Synthesis of condensed quinoxalines

Journal of the Chemical Society, Perkin Transactions 1, 1980
Condensation of 2-chloro- and 2,3-dichloro-quinoxalines with alk-1-ynes in the presence of bis(triphenylphosphine)palladium(II) dichloride and copper(I) iodide gives mono- and di-alkynylquinoxalines. Addition of amines to these products gives stable enamines; hydration gives 2′-oxoalkyl compounds which exist predominantly in the intramolecularly ...
Donald E. Ames, M. Ismail Brohi
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Quinoxaline-Based Cyclo(oligophenylenes)

The Journal of Organic Chemistry, 2015
A series of fully conjugated quinoxaline-based oligophenylene macrocycles is synthesized by Ni(0)-mediated Yamamoto-type diaryl homocoupling of (fluorinated) 2,3-bis(4'-bromophenyl)quinoxaline precursors. Cyclotrimers and cyclotetramers are obtained as the dominant reaction products.
Lidia, Marin, Julija, Kudrjasova, Pieter, Verstappen, Huguette, Penxten, Koen, Robeyns, Laurence, Lutsen, Dirk J M, Vanderzande, Wouter, Maes   +7 more
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ChemInform Abstract: Pyrrolo[1,2‐a]quinoxalines Based on Quinoxalines

ChemInform, 2011
AbstractReview: 65 refs.
V. A. Mamedov, A. A. Kalinin
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Amide–quinoxaline copolymers

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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Quinoxaline derivatives—III

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
Yusuf Ahmad, M.S. Habib, null Ziauddin
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Quinoxaline/phenylquinoxaline copolymers

Journal of Applied Polymer Science, 1977
AbstractThe thermal crosslinkability of the quinoxaline moiety incorporated within poly(phenylquinoxalines) was demonstrated by differential scanning calorimetry (DSC), torsional braid analysis (TBA), and high‐temperature adhesive evaluation. Several homopolymers, random copolymers, and polymer blends were prepared and evaluated.
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