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Three-Component One-Pot Synthesis of Novel Benzo[ ]1,8-naphthyridines Catalyzed by Bismuth(III) Chloride
Tangali R. Ravikumar Naik,Halehatty S. Bhojya Naik,Halehatty R. Prakasha Naik,P. J. Bindu
Organic Chemistry International , 2008, DOI: 10.1155/2008/594826
Abstract: A novel and efficient three-component one-pot synthesis of benzo[]1,8-naphthyridines by 2-amino-4-methylquinoline, aromatic aldehydes, and malononitrile was done. The reaction was catalyzed by an acidic Bismuth(III) chloride, functionalized Bismuth(III) chloride, at room temperature to give various benzo[]1,8-naphthyridines in high yields. The Bismuth(III) chloride is an environmentally friendly catalyst.
Simple and Efficient Synthesis of 2,7-Difunctionalized-1,8-Naphthyridines  [PDF]
S. Goswami,R. Mukherjee,R. Mukherjee,S. Jana,A. Maity,A. Adak
Molecules , 2005, DOI: 10.3390/10080929
Abstract: The syntheses in good yields of some new difunctionalized 1,8-naphthyridines 4, 6, 8 and 9 and a novel triethylene glycol ether-linked dinaphthyridine, 10a, along with the mononaphthyridine-linked ether alcohol 10b are described. An improved and milder method for the synthesis of 2,7-diamino-1,8-naphthyridine (14) is also reported.
General Pathway for a Convenient One-Pot Synthesis of Trifluoromethyl-Containing 2-amino-7-alkyl(aryl/heteroaryl)-1,8-naphthyridines and Fused Cycloalkane Analogues  [PDF]
Helio G. Bonacorso,Rosália Andrighetto,Nícolas Krüger,Nilo Zanatta,Marcos A. P. Martins
Molecules , 2011, DOI: 10.3390/molecules16042817
Abstract: A convenient and general method for the synthesis in 26–73% yields of a new series of 7-alkyl(aryl/heteroaryl)-2-amino-5-trifluoromethyl-1,8-naphthyridines from direct cyclocondensation reactions of 4-alkoxy-1,1,1-trifluoroalk-3-en-2-ones [CF3C(O)CH=C(R1)OR, where R1 = H, Me, Ph, 4-MePh, 4-OMePh, 4-FPh, 4-BrPh, 4-NO2Ph, 2-furyl, 2-thienyl and R = Me, Et] with 2,6-diaminopyridine (2,6-DAP), under mild conditions, is described. Another synthetic route also allowed the synthesis of 2-amino-5-trifluoromethyl-cycloalka[b][1,8]naphthyridines in 33–36% yields, from direct or indirect cyclo-condensation reactions of five-, six- and seven-membered 2-trifluoroacetyl-1-methoxy-cycloalkenes with 2,6-DAP.
Fluorescent 2,7-Dialkylamino-[1,8]-Naphthyridines: Preparation and Spectroscopic Properties
Christoph Hoock,J?rg Reichert,M. Schmidtke
Molecules , 1999, DOI: 10.3390/41000264
Abstract: Substitution of 4-methyl-[1,8]-naphthyridine in 2 and 7 position by alkylamines leads to highly fluorescent compounds. The arrangement of hydrogen donor and acceptor groups of these naphthyridines allows interactions with guanine and guanine cytosine base pairs. The described synthesis offers easy access to these small and stable fluorescent probes.
Spectral Characteristics of 2,7-Naphthyridines  [PDF]
Eugen Barbu,Dan Mihaiescu,Flavian Cuiban
Molecules , 2000, DOI: 10.3390/50700956
Abstract: Substituent increments for the calculation of 1H- and 13C-NMR spectra and the MS characteristics of 2,7-naphthyridines substituted on one ring are presented.
The radicals of (Braided) Lie algebras  [PDF]
Lingwei Guo,Shouchuan Zhang,Junqin Li
Mathematics , 2009,
Abstract: The general theory of the radicals of Lie algebras are established. Baer radicals of untwisted affine Lie algebras are found.
A Class of Continued Radicals  [PDF]
Costas J. Efthimiou
Mathematics , 2012,
Abstract: We compute the limits of a class of continued radicals extending the results of a previous note in which only periodic radicals of the class were considered.
Electron transfer reactions of piperidine aminoxyl radicals
Fa Zhang,YouCheng Liu
Chinese Science Bulletin , 2010, DOI: 10.1007/s11434-010-3255-8
Abstract: This review article summarizes the electron transfer reactions of piperidine aminoxyl radicals. Electrochemical studies revealed the single electron transfer nature of piperidine aminoxyl radicals. In solution, piperidine aminoxyl radicals serve as single electron transfer oxidation reagent to react with various biologically interesting molecules such as glutathione, cysteine, ascorbic acid, and amines. The reaction product distribution, reaction kinetics, intermediates, and the reaction features in biological mimic environments including micelles and cyclodextrins were investigated. Oxoammonium salts, the one-electron transfer oxidation products of piperidine aminoxyl radicals, are agents of organic synthesis to selectively generate ketones or di-ketones from alcohols or ketones bearing α-methylene group under mild conditions. The new reactions of oxoammonium salts with aromatic amines, phenols, heterocycles including phenothiazines, papaverine, and bilirubin are also illustrated.
Physiology of free radicals  [PDF]
Stevanovi? Jelka,Borozan Sun?ica,Jovi? Slavoljub,Ignjatovi? Igor
Veterinarski Glasnik , 2011, DOI: 10.2298/vetgl1102095s
Abstract: Free radicals imply that every atom, molecule, ion, group of atoms, or molecules with one or several non-paired electrons in outer orbital. Among these are: nitrogenoxide (NO ), superoxide-anion-radical (O2 -), hydroxyl radical (OH ), peroxyl radical (ROO ), alcoxyl radical (RO ) and hydroperoxyl radical (HO2 ). However, reactive oxygen species also include components without non-paired electrons in outer orbital (so-called reactive non-radical agents), such as: singlet oxygen (1O2), peroxynitrite (ONOO-), hydrogen-peroxide (H2O2), hypochloric acid (eg. HOCl) and ozone (O3). High concentrations of free radicals lead to the development of oxidative stress which is a precondition for numerous pathological effects. However, low and moderate concentrations of these matter, which occur quite normally during cell metabolic activity, play multiple significant roles in many reactions. Some of these are: regulation of signal pathways within the cell and between cells, the role of chemoattractors and leukocyte activators, the role in phagocytosis, participation in maintaining, changes in the position and shape of the cell, assisting the cell during adaption and recovery from damage (e.g.caused by physical effort), the role in normal cell growth, programmed cell death (apoptosis) and cell ageing, in the synthesis of essential biological compounds and energy production, as well as the contribution to the regulation of the vascular tone, actually, tissue vascularization.
Solution of Polynomial Equations with Nested Radicals  [PDF]
Nikos Bagis
Mathematics , 2014,
Abstract: In this note we present solutions of arbitrary polynomial equations in nested periodic radicals.
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