- The Structure of +. and + Ions Formed from Vinylimidazoles, Studied by Collisionally Activated Dissociation Mass Spectrometry
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Mass spectra of the three isomeric vinylimidazoles have been compared and the structures of the fragment ions +. and + have been investigated by collisionally activated dissociation mass spectrometry.The greater part of the non-decomposing ions m/z 68 from 2-vinylimidazole and from 2-imidazolecarboxylic acid methyl ester, and a minor part of this ion formed from the free acid, all have the same structure: the imidazole ring system, with hydrogens at both nitrogen atoms but none at C(2).An analogous structure, with an ethynyl group at C(2), is proposed for the m/z 93 ion from 2-vinylimidazole.
- Tilborg, M. W. E. M. van,Houte, J. J.,Thuijli, J. van
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- 5-(1-(IMIDAZOL)METHYL)-3,3-DISUBSTITUTED-2(3H)FURANONE DERIVATIVES
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Furanone compounds and compositions having anticholinergic activity are described. The compounds have the formula: STR1 wherein: the dashed line indicates either the 4,5-unsaturated or the 4,5-dihydrofuranone ring;R 1 and R 2 may be the same or different and are hydrogen, thienyl, furanyl, or cycloalkyl (C. sub.3-C 6), benzyl, phenyl, substituted phenyl or substituted benzyl wherein the phenyl or benzyl group may be substituted with halogen, trifluoromethyl, lower alkyl, lower alkoxy or hydroxy;R. sub.3, R 4 and R 5 may be the same or different and are hydrogen, lower alkyl, lower alkyl substituted with a halogen, alkoxy, amino or carboxylic acid group, an alkyl or alkylene bridge between R 4 and R. sub.5 or R 3 and the ring N, trifluoromethyl, nitro, a cycloalkyl group containing 3 to 6 carbons, halogen, benzyl, phenyl, substituted phenyl or substituted benzyl, for which the substituents are the same as those set forth for R 1 and R 2 substituted benzyl or phenyl.R 6 in the dihydrofuranone series is hydrogen or lower alkyl.Also described are the pharmaceutically acceptable quaternary alkyl and acid addition salts of such compounds. The compounds are particularly useful in the treatment of neurogenic bladder disorder and chronic obstructive pulmonary diseases.
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- Diazafulvenones. Thermal Isomerizations and Eliminations in Alkoxycarbonyl and Anilinocarbonyl Derivatives of Imidazole
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4-Carbonyl-4H-imidazole (10) and 2-carbonyl-2H-imidazole (11) are formed by flash vacuum pyrolysis of methyl 4- and 2-imidazolecarboxylates, respectively. 10 and 11 dimerize to diketopiperazines 14 and 16, respectively.The same products are also obtained from 4- and 2-(anilinocarbonyl)imidazoles, respectively.Methyl imidazole-1-carboxylate (4) on pyrolysis gives a ca. 1:1 mixture of the same ketenes 10 and 11, which dimerizes to a 1:2:1 ratio of diketopiperazines 14-16.In contrast, ethyl imidazole-1-carboxylate gave CO2, ethylene, and imidazole as the major products.The pyrolysis reactions were monitored by low-temperature infrared and high-temperature mass spectrometry.
- Maquestiau, A.,Tommasetti, A.,Pedregal-Freire, C.,Elguero, J.,Flammang, R.,et al.
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p. 306 - 309
(2007/10/02)
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