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1.
The condensation of 1,5-diaminoimidazoles with ethyl aceto-acetate gives two types of compounds: imidazo[1,5-b]-1,2,4-triazepinones and imidazo[4,5-b]pyridinones. The structure of these compounds is demonstrated by rmn and mass spectroscopy. The formation of imidazo[4,5-b]pyridinones from imidazo[1,5-b]-triazepinones through a new transposition is also shown. 相似文献
2.
R. Faure J. P. Galy E. J. Vincent J. Elguero 《Magnetic resonance in chemistry : MRC》1978,11(10):507-509
We have demonstrated that the compounds obtained by quaternization of thiazolo[3,2-d]tetrazole, and two of its derivatives, 3-phenyl-thiazolo[3,2-d]tetrazole and tetrazolo[5,1-b]benzothiazole, are tetrazolium salts. The quaternization effects are discussed as a function of the 13C NMR results. 相似文献
3.
Michel Farnier Michle Brost Bernard Hanquet Roger Guilard 《Journal of heterocyclic chemistry》1986,23(2):513-516
Thermal decomposition of azido-1,2-dithienylethenes 1 gave thienyl 4H-thieno[3,2-b]pyrroles 3 . For the 3,4-disubstituted thiophene derivatives 2 , the same reaction led to the amino-1,2-dithienylethenes 4 . In contrast, only azido-1,2-dithienylethanes 7 led to thienyl-5,6-dihydro-4H-thieno[3,4-b]pyrroles 8 . The structure of the obtained derivatives was established on the basis of 1H nmr, ir, and mass spectral data. 相似文献
4.
An example of stereospecific and stereoselective reactions is described concerning the cycloaddition of benzonitrile oxyde with 1,2-dimethyl-5-diphenyl-3-pyrazoline. The structure of the two epimeric 5,6-dimethyl 3,4-dimethyl[4,3-d]pyrazolidinoisoxazo-lines-2 was proved by the means of chemical and physical methods. The conversion of one epimeric product to another more stable is achieved and discussed. 相似文献
5.
Jean-Marie Webert Denise Cagniant Paul Cagniant Gilbert Kirsch Jean-Victor Weber 《Journal of heterocyclic chemistry》1983,20(1):61-64
The influence of annelaction and of the heteroatom upon the reactity of some haterocyclic analogus of phenanthrene with a pyrrole nucleos was tested toward acetylation and lithiation. If methy-l[1]benzofuro-[3,2-b]pyrrole was acetylated only in the 2-position, the sulfer and selenious analogues with [3,2-b] and [2,3-b] annelarion were acetylated in the -2 and -3 position. No reaction at all or only with poor yield (in the oxygenated series) was observed with butyllithium except on the case of l-methyl[1]benzoselenono[2,3-b]pyrrole, where the opening of the selenophene nucleos gives, after carbonation and action of diazomethane, l-methyl-2-methoxycarbony 1-3-(o-methylselenophenyl) pyrrole. 相似文献
6.
Henri Jolibois Joël Vebrel Lahcene Ouahab Ahmed Boultif Daniel Grandjean 《Helvetica chimica acta》1988,71(1):254-257
Hydrogenation of Flavylium Salts: Formation of Heptacyclic compounds; X-Ray Crystal Structure of 2-[10b,10c,16,16a-Tetrahydro-16,16a-dimethyl-10b,16-methylene-5aH-di[1]benzopyrano[4,3-b:3′,4′ -c; 2,3:2′,3′][1]benzoxepin-5a-yl]phenol The hydrogenation of flavylium salts 1 either by catalytic reduction or by chemical reduction afforded the unexpected heptacyclic compound 2 , the structure of which was determined by X-ray analysis. The latter was confirmed by 1H-NMR and mass spectra. 相似文献
7.
Jean-Paul Affane-Nguema Jean-Pierre Lavergne Philippe Viallefont 《Journal of mass spectrometry : JMS》1977,12(3):136-144
The mass spectra of 21 1,4-pyrazolo[3,4-b]diazepines are reported and analysed. Each of the five structures of the diazepine ring present is characterized by a particular group of fragmentations; among them one is common to all the compounds under study: the cleavage of C-5? C-6 and C-7? N-8 bonds leading to pyrazoloimidazoles ions. 相似文献
8.
The orientation of the cycloaddition of diazomethane on unsaturated branchedchain sugars has been studied. For 3-C-cyanomethylidene-3-deoxy-1,2-O-isopropylidene-α-D-glycero-tetrofuranose the orientation was ‘normal’ and did not depend on the configuration at the double bond. The same situation prevailed with derivatives of 3-deoxy-1,2:5,6-di-O-isopropylidene-3-C-methylidene-α-D-xylo-hexofuranose. For the 3-C-acylmethylidene- and the 3-C-cyanomethylidene-3-deoxy-1,2:5,6-di-O-isopropylidene-α-D-ribo-hexofuranoses, the trans-(H–C(3′)–C(2))-isomer gave the ‘normal’ cycloadduct whereas the cis-isomer gave predominantly the αabnormal spiro-pyrazoline. This observation represents the first instance where the regioselectivity of a cycloaddition reaction is affected by the geometrical isomerism of the dipolarophile. The most probable explanation of the phenomenon is the conformational perturbation about the C(4)--C(5) bond of the unsaturated sugars induced by a change in the configuration at C(3). The consequence of that ‘conformational transmission’ of a difference in configuration at C(3) is that the steric crowding on the cis- than in the trans-isomer. Several novel examples of a new series of C-glycosylidenic derivatives, the spiro-pyrazolines, are described. 相似文献
9.
Electrochemical reduction of [1]benzopyranno[4,3-e]-as-triazinones gives 1,4-dihydro derivatives which can either rearrange into 4,4a-dihydro compounds or be reduced with ring contraction into benzopyranno-imidazolones. The reaction of Grignard reagents on benzopyrannotriazines leads to a reduction in –α position of the benzene ring (4,4a-dihydro). Electrochemical reduction gives the 1,4-dihydro derivative which rearrange into the 1,10a-dihydro compound. The 1,4-dihydro derivatives are reduced with triazine ring contraction to give benzopyrannoimidazoles. Dihydro-1,10a compounds can be reduced into imidazoles or into tetrahydro derivatives. 相似文献
10.
1,4-Diphenyl-2,3-dibenzylbutadiene is a good precursor of o-dibenzylated compounds by cycloaddition reactions. It gives a naphthacene derivative by a three step synthesis from ethyl oxalate. Sulfur treatment of new o-dibenzylated aromatic compounds gives benzo[c]thiophens, and also naphtho[2,3-c]thio-phens. Carbocyclization reactions appear with benzo[a]ace-anthrylene and dihydroindeno[2,l-a]fluorenc formation. 相似文献
11.
The reaction of 3,4-diamino-5-oxo-4,5-dihydro-l,2,4-triazine or its 6-methyl or 6-phenyl substituted derivatives and ethyl acetoacetate gave three compounds: 4,7-dioxo-9-methyl-1,4,6,7-tetrahydro-as-triazino[4,3-b]-1,2,4-triazepine in poor yield, isomeric 4,9-dioxo-7-methyl-1,4,8,9-tetrahydro-as -triazino[4,3-b]-1,2,4-triazepine and by competitive cyclisation, 2-methyl-7-oxo-3,7-dihydro-s-triazolo[3,2-c]-1,2,4-triazine. By condensation of 3-methylamino-4-amino-5-oxo-4,5-dihydro-1,2,4-triazine with ethyl acetoacetate, the formation of 4,9-dioxo-7,10-dimethyl-4,8,9,10-tetrahydro-as-triazino[4,3-b]-1,2,4-triazepine was strongly favored. 相似文献
12.
Reaction of 2-t-butylthiobenzaldehyde with N-(2-dialkylaminoethyl)-cyanacetamides followed by heating of the resulting 3-(2-t-butylthiophenyl)-2-cyanoacrylamides in polyphosphoric acid leads to the formation of 3-carboxamido-2-imino-2H-benzo[b][l]thiopyrann intermediates which afford thiocoumarins on hydrolysis. The authors postulate the intermediate formation of a thiophenate ion by an electronic mechanism involving six centers. 相似文献
13.
Colette Deschamps-Vallet Michle Meyer-Dayan Jean Andrieux Jacques Riboulleau Bernard Bodo Darius Molho 《Journal of heterocyclic chemistry》1977,14(3):489-492
5-Oxo-5H,7H-[2]benzopyrano[4,3-b][1]benzopyran ( 2 ) has been synthesized from 3-(o-hydroxybenzylidene)isochroman-1,4-dione ( 3 ) by reductive cyclization, and from 5H,7H[2]benzo-pyrano[4,3-b][1]benzopyran-5,7-dione ( 4 ) by selective hydro-genation. This second method affords the dihydro compound 6 or 6a,12a-dihydro-5H,7H-[2]benzopyrano[4,3-b] [1 ]benzopyran-5-one as reaction time increases. 相似文献
14.
Etienne Rougeot Henri Moskowitz Marcel Miocque 《Journal of heterocyclic chemistry》1983,20(5):1407-1409
Acetylenic amindines HC≈?C·(CH2)n·C(?NH)NH2 give, by condensation with β-ketoesters, pyrimidones substituted on carbon 2 by an acetylenic chain. Two types of evolution are observed when compounds are heated without any catalyst. The minor route is a cyclization by attack on a triple bond by the amidic nitrogen atom. The main reaction is a cycloaddition involving the non activated triple bond and an azadienic system, leading to non isolated tricyclic intermediates which retrocyclize to stable bicyclic compounds. 相似文献
15.
Henri J.-M. Dou Maria Ludwikow Parina Hassanaly Jacky Kister Jacques Metzger 《Journal of heterocyclic chemistry》1980,17(2):393-395
A general study of the chemical behavior of heterocyclic anions, dianions and dianionic reagents under phase transfer catalysis conditions allowed us to synthesize various heterocyclic compounds such as imidazo[2,1-b]thiazole and derivatives; imidazo[2,1-b]thiazine and imidazo[2,1-b]benzothiazepine. Reaction conditions e.g., catalyst, solvent, temperature, etc., are indicated. 相似文献
16.
Max Robba Jean-Charles Lancelot Daniel Maume Alain Rabaron 《Journal of heterocyclic chemistry》1983,20(2):427-430
The 3H-5-(3′-indazolyl)-1,3,4-oxadiazol-2-one was obtained by cyclising the hydrazide of the 3-indazolecarboxylic acid with carbonyl chloride. The structure was assigned by 13C nmr and mass spectrometry comparing the 2H, 3H-triazino-1,2,3[4,5-b]indazoledione-1,4. Rearrangement into 3H-5-(3′-indazolyl)-1,3,4-oxadiazol-2-one precedes the fragmentation of 2H,3H-triazino-1,2,4-[4,5-b]indazoledione-1,4 upon electron-impact. 相似文献
17.
Generally, 4,5-dihydro-3triazinones have been prepared by a basic hydrolysis of 3-methylmercapto-4,5-dihydrotriazines. Of the serveral methylation methods, namely, diazomethane, methyliodide, dimethyl sulfate all in the presence of sodium methylate or silver carbonate, only methyl bromide in the presence of phase transfer catalyst was sucessful in producing all of the N-2 and/or N-4 methylate compounds. Two unequivocal syntheses of dihydrotriazolo[4,3-b]triazine are reported. 相似文献
18.
C -Glycosylic derivatives XXXII. Synthesis of spiro-C -glycosylidenic derivatives via nucleophilic cyclization. On treatment with compounds bearing two nucleophilic groups as ethylenediamine, o-phenylenediamine or their monooxa or monothia analogues, 1,2:5, 6-di-O-isopropylidene-α-D -ribo-hexofuranos-3-ulose gave with excellent yields the corresponding spiro-C-glycosylidenic derivative; for example, when using o-phenylenediamine, a spirobenzimidazoline ( 5 ) was obtained. The latter compound underwent, on oxidation, a ring expansion to a morpholinobenzimidazole ( 8 ). Spirobenzodiazepines, spirobenzooxazepines and spirobenzothiazepines were formed when applying the same type of cyclization reaction to 3-C-acetylmethylene-3-deoxy-1,2:5,6-di-O-isopropylidene-α-D -ribo- and α-D -xylo-hexofuranoses. 相似文献
19.
Bernard Laude Mohamed Soufiaoui Et Jean Arriau 《Journal of heterocyclic chemistry》1977,14(7):1183-1190
The reactivity of N-methylindole towards diarylnitrilimines has been studies. The cycloadducts are 8-methyl-3a,8a-dihydro-pyrazolo[3,4-b] indole derivatives. The structure reported was assigned on the bases of satisfactory analytical, spectroscopic and chemical data. An interpretation based on the second order perturbation method of frontier orbitals is in agreement with the observed regiospecificity. 相似文献
20.
J.-P. Affane-Nguma J.-P. Lavergne Ph. Viallefont 《Journal of heterocyclic chemistry》1977,14(6):1013-1019
Reduction and methylation of pyrazolo[ 3,4-b ]diazepines have been effected by several methods. According to the reducing agents used, it has been possible to reduce selectively the C?N double bond, the carbonyl group, to reduce the diazepinone rings completely and to reduce partially or completely the insaturated parts of the (6H)pyrazolodiazepines. Methylation on the amide nitrogen, on oxygen of the same function, and in a few cases on the C6 carbon of the pyrazolodiazepinones and finally on the 4 position in tetrahydropyrazolodiazepinones have been obtained. 相似文献