Untersuchungen an quartären Pyridinium-Salzen, III / Investigations of Quaternary Pyridinium Salts, III

Four molecules of quaternary salts of nicotinamide form a condensation product of structure 2. It has been studied with the model substances 1d—q which elements of structure promote or prevent formation of the cyclocondensation product.

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Untersuchungen an quartären Pyridinium-Salzen, II / Investigation of Quaternary Pyridinium-Salts, II

Zeitschrift für Naturforschung B ◽

10.1515/znb-1973-7-817 ◽

1973 ◽

Vol 28 (7-8) ◽

pp. 471-474 ◽

Cited By ~ 8

Author(s):

Wolf-Hellmut Gündel

Keyword(s):

Condensation Product ◽

Pyridinium Salts ◽

Quaternary Pyridinium Salts ◽

Quaternary Salts

Four molecules of quaternary salts of nicotinamide (1 and 4) form a chloroform-soluble condensation product of structure 2 and 5 by action of base under elimination of HX.

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Untersuchungen an quartären Pyridinium-Salzen, XVII Cyclopeptidartige Verbindungen aus Salzen von Nikotinoylaminosäureamiden/Investigations of Quaternary Pyridinium Salts, XVII Cyclopeptide-like Substances from Salts of the Amides of Nicotinoylamino Acids

Zeitschrift für Naturforschung B ◽

10.1515/znb-1985-0227 ◽

1985 ◽

Vol 40 (2) ◽

pp. 305-312 ◽

Cited By ~ 3

Author(s):

Wolf-H. Gündel

Keyword(s):

Amino Acid ◽

Pyridinium Salts ◽

Acid Moiety ◽

Quaternary Pyridinium Salts ◽

Quaternary Salts ◽

Amino Acid Moiety

Abstract The amides of nicotinoylamino acids were prepared and alkylated to the quaternary salts 1f-n. The α-amino acid moiety in 1 is S configurated. The salts 1 cyclise under the influence of base to give the cyclopeptide-like substances 4, 5 and 7, with seven-or fourteen (sixteen, eighteen-) membered rings, respectively.

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Untersuchungen an quartären Pyridiniumsalzen, IX [1] Pyridiniumsalze mit Amidingruppe. Darstellung und Reaktion mit Base / Investigations of Quaternary Pyridinium Salts, IX [1] Pyridinium Salts with Amidine Group. Preparation and Reaction with Base

Zeitschrift für Naturforschung B ◽

10.1515/znb-1979-0727 ◽

1979 ◽

Vol 34 (7) ◽

pp. 1019-1023 ◽

Cited By ~ 3

Author(s):

Wolf-Hellmut Gündel

Keyword(s):

Primary Amine ◽

Alkylating Agents ◽

Pyridinium Salts ◽

Quaternary Pyridinium Salts ◽

Quaternary Salts ◽

Derivatives Of

Abstract 3-Pyridinecarboximidamide gave with alkylating agents quaternary salts (2), that rearrange on addition of anionic base to 2-amino-pyridinecarbaldehyde (3). Derivatives of 3 can be obtained by reaction of 3-cyano-pyridinium salts with primary amine on addition of anionic bases

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Untersuchungen an quartären Pyridinium-Salzen, IV / Investigations of Quaternary Pyridinium Salts, IV

Zeitschrift für Naturforschung B ◽

10.1515/znb-1975-7-828 ◽

1975 ◽

Vol 30 (7-8) ◽

pp. 616-621 ◽

Cited By ~ 6

Author(s):

Wolf-Hellmut Gündel

Keyword(s):

Pyridinium Salts ◽

Quaternary Pyridinium Salts ◽

Quaternary Salts

Quaternary salts of nicotinamide react in presence of bases with chlorofrom to substituted 2- (or 3-)azabicyclo[4,1,0]hepten-3 (or -4). An intermediate is isolated.

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ChemInform Abstract: STUDIES ON QUATERNARY PYRIDINIUM SALTS, VIII. CYCLOTETRACONDENSATES WITH ADDITIONAL FUNCTIONAL GROUPS FROM QUATERNARY SALTS OF NICOTINAMIDE

Chemischer Informationsdienst ◽

10.1002/chin.197840253 ◽

1978 ◽

Vol 9 (40) ◽

Author(s):

W.-H. GUENDEL ◽

W. KRAMER

Keyword(s):

Functional Groups ◽

Pyridinium Salts ◽

Quaternary Pyridinium Salts ◽

Quaternary Salts

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A new heterocyclic ring closure in ferricyanide oxidation of 2,4,6-triphenylpyridinium salts

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19833307 ◽

1983 ◽

Vol 48 (11) ◽

pp. 3307-3314 ◽

Cited By ~ 6

Author(s):

Petr Nesvadba ◽

Petr Štrop ◽

Josef Kuthan

Keyword(s):

Alkaline Solution ◽

Heterocyclic Ring ◽

Potassium Ferricyanide ◽

Probable Mechanism ◽

Ring Closure ◽

Pyridinium Salts ◽

Mechanism Of Formation ◽

Pyrrole Derivatives ◽

Quaternary Pyridinium Salts ◽

Heterocyclic Derivatives

The quaternary pyridinium salts Ia-Ic react with alkaline solution of potassium ferricyanide to give the condensed heterocyclic derivatives IIIa, b, IV, whereas the salts Id-If give the pyrrole derivatives IIa-IIc under the same conditions. The diaza heterocycle IIIa reacts with methyl iodide to give methoiodide V, whereas by action of bromine it produces two monobromo derivatives VIa, b. The pyrrole derivatives IIa, b give monobromo derivatives IId, e on bromination. A probable mechanism of formation of the heterocyclic derivatives is discussed.

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Sterically Crowded Heterocycles. III. A General Approach to Imidazo[1,2-a]pyridines by Ferricyanide Oxidation of Quaternary Pyridinium Salts

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19960126 ◽

1996 ◽

Vol 61 (1) ◽

pp. 126-138 ◽

Cited By ~ 6

Author(s):

Richard Kubík ◽

Stanislav Böhm ◽

Iveta Ruppertová ◽

Josef Kuthan

Keyword(s):

Potassium Hydroxide ◽

Potassium Ferricyanide ◽

Pyridinium Salts ◽

Oxidizing Agents ◽

Quaternary Pyridinium Salts ◽

Substituted 1

Substituted 1-(pyridin-2-yl)-2,4,6-triphenylpyridinium perchlorates 1b-1e were converted with potassium ferricyanide and potassium hydroxide to sterically crowded 2-phenyl-3-[(Z)-1,3-diphenyl-3-oxopropenyl]imidazo[1,2-a]pyridines 2b-2e accompanied by minor isomeric 2-benzoyl-3,5-diphenyl-1-(pyridin-2-yl)pyrroles 3c-3e. 4-Phenyl-2,6-di(4-substituted phenyl)-1-(pyridin-2-yl)pyridinium salts 4a, 4b gave exclusively corresponding imidazo[1,2-a]pyridines 5a, 5b while the ferricyanide oxidation of 1-(5-iodo- and 5-cyanopyridin-2-yl)-2,4,6-triphenylpyridinium perchlorates 6a, 6b led to mixtures of major imidazo[1,2-a]pyridines 7a-7c and minor pyrroles 8a-8c. Some mechanistic aspects of the oxidation procedure are discussed in connection with a resistance of 2,6-diphenyl-1,3,5-trimethylpyridinium perchlorate (9c) towards the oxidizing agents.

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