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1.
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   

2.
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   

3.
Several new bis-s-triazolo[4,3-b:4,3-d]-1,2,4-triazepines were synthesized from appropriate 8-hydrazino-s-triazolo[4,3-b]-1,2,4-triazepines by condensation with formic and acetic acid.  相似文献   

4.
2-, 3-, and 4-Fluorinated analogs of the carcinogenic [1]-benzothiopyrano[4,3-b]indoles and of 6H[1]benzothiopyrano-[4,3-b]quinolines have been synthesized from the corresponding fluorothiochromanones. Nmr spectral data (at 60 Mc) of the six base molecules are reported. Biological tests for the possible carcinogenic activity of these new compounds, currently under way, have already shown one of them to be a powerful sarcomagen.  相似文献   

5.
In boiling diphenylether phenylhydrazine reacts with 1,2-dihydro-2-oxo-4-hydroxypyridines to give 3,4-dihydro-4-oxo(9H)-pyrido[4,3-b]indoles (γ-carbolines) in one step. Nucleophilic displacement of their 4-chloro derivatives by secondary amines affords both 3,4-disubstituted γ-carbolines and chlorination of 2,3-dimethyl-4-oxo(9H)pyrido[4,3-b]indoles, as well as methylation of 2-methyl-4-chloro-(9H)pyrido[4,3-b]indole leads to derivatives in the (3H)4-substituted pyrido[4,3-b] indole series.  相似文献   

6.
Schiff bases generated in situ from substituted anilines and 2-allyloxybenzaldehyde underwent acid-catalyzed intramolecular Diels-Alder reaction followed by dehydrogenation to give 6H-chromeno[4,3-b]-quinolines. Under analogous conditions, derivatives of 2-allyloxynaphthalene-1-carbaldehyde were converted into 8a,9,14,14a-tetrahydro-8H-benzo[5,6]chromeno[4,3-b]quinolines. Possible dehydrogenation mechanisms are discussed. Original Russian Text ? M.M. Tomashevskaya, O.A. Tomashenko, A.A. Tomashevskii, V.V. Sokolov, A.A. Potekhin, 2007, published in Zhurnal Organicheskoi Khimii, 2007, Vol. 43, No. 1, pp. 75–80.  相似文献   

7.
Several thieno[2,3-b]quinolines 6a-i have been synthesized. These compounds were used as key intermediates in the synthesis of oxazino[4′,5′:4,5]thieno[2,3-b]quinoline 8 , pyrimido[4′,5′:4,5]-thieno[2,3-b]quinolines 9–12 , triazino[4′,5′:4,5]thieno[2,3-b] quinolines 14 and imidazo[4′,5′:4,5]-thieno[2,3-b]quinolines 17 .  相似文献   

8.
The nucleophilic and electrophilic substitutions of 6-substituted 9,9-dimethyl-9H-imidazo[1,2-b]pyrazolo- [4,3-d]pyridazines 2 , nucleophilic substitutions of 6-substituted 9,9-dimethyl-9H-pyrazolo[4,3-d]-s-triazolo- [4,3-b]pyridazines 7 and some other transformations to give compounds 3 and 8 , respectively, were studied. It was shown that both heterocyclic systems are stable under the conditions employed in these transformations.  相似文献   

9.
Ribosylation of 3-amino-5H-[1,2,4]triazolo[4,3-b][1,2,4]triazole ( 1 ) with l-O-acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose and stannic chloride resulted in the following protected nucleoside analogs: 3-amino-1-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)[1,2,4]triazolo[4,3-β][1,2,4]triazole ( 4 ), 3-amino-1-(2,3,5-tri-O-benzoyl-α-D-ribofuranosyl)[1,2,4]triazolo[4,3-β][1,2,4]triazole ( 5 ), 3-amino-1-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)[1,2,4]triazolo[4,3-β][1,2,4]triazole ( 5 ), and 3-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl) amino-5H-[1,2,4]triazolo[4,3-b]-[1,2,4]triazole ( 7 ). Compounds 4–6 were deprotected to 3-amino-1-β-D-ribofuranosyl[1,2,4]triazolo[4,3-b][1,2,4]-triazole ( 3 ), 3-amino-1-α-D-ribofuranosyl[1,2,4]triazolo[4,5-b][1,2,4]triazole ( 8 ), and 3-imino-2H-2-β-D-ribo-furanosyl[1,2,4]triazolo[4,3-b][1,2,4]triazole ( 9 ), while 7 could not be deprotected without decomposition. Compounds 1, 4, 6, 7 , and 9 were screened and found to have no antiviral activity.  相似文献   

10.
Syntheses of substituted pyrazolo[3,4-b]quinolines, 3,4-dihydro-4-oxopyriraido[4′,5′:4,5]theino[2,3-b]quinoline and 12-phenylpyrido[1′,2′:1,2[pyrimido[4,5-b]quinoline are described.  相似文献   

11.
A new snythesis of 6H-pyrido[4,3-b]carbazoles is described starting from substituted cyclohexanones involving the combination of Borsche's carbazole preparation and Cranwell and Saxton's ellipticine synthesis where the starting materials are easily available. The dehydrogenation step is accomplished at an early stage. In some cases (11-desmethyl ellipticines derivatives), 7H-pyrido[3,4-c]carbazoles were also obtained.  相似文献   

12.
The condensation of 3,4-diamino 1,2,4-triazole with ethyl aceloacelate gave 6-methyl-8,9-dihydro(7H)-s-triazolo[4,3-b]-1,2,4-triazepin-8-one ( 2 ); 2 has been caracterized by nmr spectroscopy and by comparison with its methylated derivative prepared in an unambigous manner.  相似文献   

13.
The reactions of 2-dicyanomethylidene-3-ethoxymethylidene-2,3-dihydroindole with hydrazine hydrate and phenylhydrazine afforded 2,3-diamino-4-cyanopyrido[4,3-b]indole and 3-amino-2-anilino-4-cyanopyrido[4,3-b]indole, respectively, and the reactions of the latter compounds with dimethylformamide diethyl acetal were studied. The reactions of 2,3-diamino-4-cyanopyrido[4,3-b]indole with benzaldehyde, ethyl acetoacetate, and acetylacetone were investigated. First representatives of new heterocyclic systems, viz., [1,2,4]triazolo[1’,5’:1,6]-pyrido[4,3-b]indole and pyrazolo[1’,5’:1,2]pyrido[4,3-b]indole, were synthesized. The structure of ethyl 6-cyano-5-[(E)-(dimethylamino)methylideneamino]-2-methyl-7H-pyrazolo-[1’,5’:1,2]pyrido[4,3-b]indole-1-carboxylate was established by X-ray diffraction.  相似文献   

14.
An efficient and convenient one-pot intramolecular aza Diels-Alder approach for the synthesis of dihydrochromeno[4,3-b]pyrrolo[3,2-f]quinolines has been reported. Particularly valuable features of this methodology include simple execution, inexpensive catalyst, and good product yields.  相似文献   

15.
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   

16.
Substituted amides of 2-hydrazino- and 2-ethylhydrazinocinchoninic acids react with pyruvic acid and its ethyl ester to give amides of 3-methyl-4-oxo-1,2,4-triazino[4,3-a]quinoline-10-carboxylic acid. On reaction with aromatic aldehydes they are converted into amides of 2-ethyl-3-phenyl-2,3-dihydro-1,2,4-triazolo[4,3-a]quinoline-9-carboxylic acid, or, in the case of unsubstituted hydrazines, into amides of 2-arylidene-hydrazinocinchoninic acid, which was oxidized to substituted 1,2,4-triazolo[4,3-a]quinolines.Perm Pharmaceutical Academy, Perm 614600. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 701–705, May, 1977.  相似文献   

17.
Summary. The reactions of 5-arylidene derivatives of Meldrum’s acid with ethyl vinyl ether or N-vinyl-2-oxazolidinone yielded trans-trans-(2,4:4,7)-pyrano[4,3-b]pyrans, cis-trans-(2,4:4,7)-pyrano[4,3-b]pyrans, or diastereoisomeric mixtures of pyrano[4,3-b]pyrans and reactions with 3,4-dihydro-2H-pyran afforded Michael adducts. The reactions of 5-arylidene derivatives of Meldrum’s acid with cyanoacetic acid derivatives do not provide appropriate pyrans.  相似文献   

18.
Reactions of 2-dicyanomethylidene-3-ethoxymethylidene-2,3-dihydroindole with various amines afforded enamino dinitriles and the corresponding pyrido[4,3-b]indoles (γ-carbolines). 3-Amino-4-cyano-5H-pyrido[4,3-b]indole reacted with cyclohexanone to give pentacyclic 13-amino-2,3,4,12-tetrahydro-1H-benzo[b]indolo[2,3-f]-1,8-naphthyridine. Alkylation of pyrido[4,3-b]indoles with various alkylating agents was studied.  相似文献   

19.
A new method has been developed for the synthesis of derivatives of indolo[3,2-b]quinolines-11 based on N-oxidization of 2-nitro-10-substituted indolo[3,2-b]quinolines with subsequent conversion of the mixtures obtained into 2-nitro-11-substituted indolo[3,2-b]quinolinones-11. A series of 2-nitro-11-substituted indolo[3,2-b]quinolines was prepared.  相似文献   

20.
Starting from the substituted 4,5-diaminopyrazolo[3,4-b]pyridine, derivatives of a number of tricyclic systems, viz., imidazo[4,5-d]pyrazolo[3,4-b]pyridine, pyrazolo[3,4-b][1,2,5]thiadiazolo[3,4-d]pyridine, pyrazolo[3,4-b][1,2,3]triazolo[4,5-d]pyridine, and [1,3]oxazolo[5,4-b]pyrazolo[4,3-e]pyridine, were synthesized and reaction schemes for the processes were proposed.  相似文献   

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