Results 221 to 230 of about 358,569 (255)

Hexahydrobenzothiazolo[3,2-a]pyridinium salts

Chemistry of Heterocyclic Compounds, 1988
Salts of hexahydrobenzothiazolo[3,2-a]pyridine are obtained by exchange reactions. Anions are placed in the order [(NC)2CCHC(CN)2]- > ClO4−>I3−>Br− according to the ability to displace each other. X-ray structural and spectroscopic studies establish the cis-attachment of the thiazolidine and cyclohexane rings in the hexahydrobenzothiazolo [3,2-a ...
A. M. Shestopalov, V. N. Nesterov, Yu. A. Sharanin, V. P. Litvinov, V. E. Shklover, Yu. T. Struchkov, V. K. Promonenkov   +6 more
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Oxidation of polysubstituted pyridinium salts

Collection of Czechoslovak Chemical Communications, 1982
Oxidation of 1-substituted 2,4,6-triphenylpyridinium salts Ia-Ij with potassium ferricyanide in an alkaline medium was accompanied by contraction of the pyridine ring and formation of 1,2,3,5-tetrasubstituted pyrroles II. The derivative IIf underwent facile electrophilic substitution in the position 4. Contrary to compounds Ia-Ij, the 1-substituted-2,6-
Petr Nesvadba, Josef Kuthan
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Thiazolo [3,2‐a] pyridinium salts

Journal of Heterocyclic Chemistry, 1966
AbstractThe sulfides formed by the reaction of α‐halo ketones or α‐halo acetals with 2‐mercaptopyridine may be cyclized in good yield to form thiazolo[3, 2‐a]pyridinium salts. The presence of chloro or nitro substituents on the pyridine ring does not interfere with the synthesis.
C. K. Bradsher, D. F. Lohr
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Investigation of Methyl Pyridinium-2-aldoxime Salts

Journal of Pharmaceutical Sciences, 1961
Methyl pyridinium-2-aldoxime iodide (2-PAM iodide) has been reported to be effective in preventing and overcoming the toxic effects in animals poisoned with organic phosphorus compounds that are inhibitors of the cholinesterase enzymes. In order to obtain greater water solubility of the oxime and to eliminate undesirable side effects due to the iodide ...
A A, KONDRITZER, R I, ELLIN, L J, EDBERG
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Iridium‐Catalyzed Asymmetric Hydrogenation of Pyridinium Salts

Angewandte Chemie International Edition, 2012
As one of the most straightforward and powerful approaches for the preparation of optically active compounds, asymmetric hydrogenation has been successfully used for different types of aromatic compounds, including quinolines, isoquinolines, quinoxalines, indoles, pyrroles, furans, imidazoles, and aromatic carbocyclic ring, with excellent ...
Zhi-Shi, Ye, Mu-Wang, Chen, Qing-An, Chen, Lei, Shi, Ying, Duan, Yong-Gui, Zhou   +5 more
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Oxidation of reduced triphosphopyridine nucleotide by pyridinium salts

Archives of Biochemistry and Biophysics, 1967
Abstract Certain substituted pyridinium salts are able to support oxidation of TPNH. Ferredoxin, ferredoxin-TPN reductase, and molecular oxygen are necessary. water rather than Peroxide is formed, as shown by the stoichiometry of the reaction. During the Reaction the pyridinium salts do not undergo Spectral changes.
P, Böger, A, San Pietro
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VIBRATIONAL SPECTRA OF PYRIDINIUM SALTS

Canadian Journal of Chemistry, 1961
The vibrational spectrum of the pyridinium ion, C5H5NH+, and the N-deuterated species has been studied in several pyridinium salts. By comparison with benzene and deuterobenzene (with which the pyridinium ion is isoelectronic) a fairly complete assignment has been made. The N—H bonds, which are hydrogen bonded to the anions, have stretching vibrations
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Photoinduced Intramolecular Charge Transfer and Hyperpolarizability Coefficient in Push-Pull Pyridinium Salts with Increasing Strength of the Acceptor Group.

ChemPlusChem, 2018
The synthesis of three push-pull cationic dyes is reported here together with a photophysical study carried out by stationary and ultrafast spectroscopies.
A. Cesaretti, C. Bonaccorso, F. Elisei, C. Fortuna, L. Mencaroni, A. Spalletti   +5 more
semanticscholar   +1 more source

Azulene‐substituted pyridines and pyridinium salts. Synthesis and structure. 2. Azulene‐substituted pyridinium salts

Journal of Heterocyclic Chemistry, 2007
Abstractmagnified image4‐Azulen‐1‐yl substituted 2,6‐dimethyl‐and 2,6‐diphenyl‐pyridinium salts are obtained in yields between 50 % and 100 % in the reaction of corresponding 4‐azulen‐1‐yl‐pyranylim salts and various amines. The effects of amine structure and of substitution in the heterocycle or at azulene moieties on the synthesis have been ...
Alexandru C. Razus, Liviu Birzan, Claudia Pavel, Oana Lehadus, Andreea Corbu, Filip Chiraleu, Cristian Enache   +6 more
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Pyridinium salts and dihydropyridines; mechanistic studies of the redox reaction between pyridinium salts and alkoxides in tetrahydrofuran

Journal of the Chemical Society, Perkin Transactions 2, 1977
A model system for NAD-dependent redox reactions has been designed in an attempt to assess the involvement of covalent adducts as intermediates. The system consists of 3-substituted 1-n-heptylpyridinium salts and substituted benzyl alkoxides. Although covalent adducts were found in the reaction mixture, studies of substituent effects and other ...
Alexander Shirra, Colin J. Suckling
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