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1.
Y. H. R. Jois C. D. Kwong J. M. Riordan J. A. Montgomery J. A. Secrist 《Journal of heterocyclic chemistry》1993,30(5):1289-1292
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
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.
The synthesis of 1,2,4-triazolo[4,3-b]pyridazines and the unknown ring system, pyrazino[2,3-d]-1,2,4-triazolo[4,3-b]pyridazine, has been achieved. The preparation of the new tricyclic 1,2,4-triazole was accomplished first by ring closure of the triazole ring followed by formation of the pyrazine ring. Substitution of the pyrazino[2,3-d]-1,2,4-triazolo[4,3-b]pyridazine ring system was carried out in order to provide information of its reactivity and to provide a variety of interesting compounds for biological testing. 相似文献
4.
E. M. Essassi J. P. Lavergne Ph. Viallefont J. Daunis 《Journal of heterocyclic chemistry》1975,12(4):661-663
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
5.
A. Sh. Oganisyan A. S. Noravyan M. Zh. Grigoryan 《Chemistry of Heterocyclic Compounds》2004,40(1):75-78
Novel dihydro-5H-pyrano[3',4':5',6']pyrido[2,3-d]-1,2,4-triazolo[4,3-c]pyrimidines and 1,2,3,4-tetrazolo[1,5-c]pyrimidines have been synthesized from 2-amino-3-cyano-7,7-dimethyl-7,8-dihydro-5H-pyrano[4,3-b]pyridine. 相似文献
6.
Branko Stanovnik Borut Furlan Marko Kupper Lidija Male Anton timac Miha Tiler Marko
li
ar 《Journal of heterocyclic chemistry》1988,25(2):393-398
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
7.
Charles Y. Fiakpui Oludotun A. Phillips K. S. Keshava Murthy Edward E. Knaus 《Journal of heterocyclic chemistry》1999,36(2):377-380
A group of 5-(2-chlorophenyl)-10-(substituted)-7H-pyrido[4,3-f][1,2,4]triazolo[4,3-a][1,4]diazepines 7a-c were synthesized by the acid catalyzed reaction of 5-(2-chlorophenyl)-2-hydrazino-3H-pyrido[3,4-e]-[1,4]diazepine ( 6 ) with either trimethyl orthoformate, triethyl orthoacetate or triethyl orthobenzoate, respectively. 5-(2-Chlorophenyl)-7H-pyrido[4,3-f][1,2,4]triazolo[4,3-a][1,4]diazepine ( 7a ) and 5-(2-chlo-rophenyl)-10-methyl-7H-pyrido[4,3-f][1,2,4]triazolo[4,3-a][1,4]diazepine ( 7b ) exhibited good anticonvulsant activity in the subcutaneous metrazol anticonvulsant screen which serves as a model for absence (petit mal) epilepsy. 相似文献
8.
A three step synthesis of pyrido[4,3-b]quinolines is reported. Thus, treatment of 2-hydroxy-4-arylaminopyridines under Vilsmeir-Haack conditions directly afforded 1-oxo-1,2-dihydropyrido[4,3-b]quinolines. Chlorination of these compounds gave the corresponding 1-chlorinated derivatives which were then substituted by various primary and secondary amines. 相似文献
9.
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
10.
G. Kh. Khisamutdinov V. L. Korolev T. N. Parkhomenko V. M. Sharonova E. S. Artem'eva I. Sh. Abdrakhmanov S. P. Smirnov B. I. Ugrak 《Russian Chemical Bulletin》1993,42(10):1700-1702
New methods for the synthesis of 1,2,4-triazolo[4,3-d]-1,2,4-triazolo[3,4-f]furazano[3,4-b]pyrazines with functional substituents of various types are proposed and some properties of these compounds are studied.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1776–1778, October, 1993. 相似文献
11.
Claire Ducrocq Alain Civier Jeannine Andr-Louisfert Emile Bisagni 《Journal of heterocyclic chemistry》1975,12(5):963-967
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
12.
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
13.
A. Monge Vega I. Aldana M. M. Rabbani E. Fernandez-Alvarez 《Journal of heterocyclic chemistry》1980,17(1):77-80
This paper describes the synthesis of the previously unknown 11H-1,2,4-triazolo[4,3-b]pyridazino[4,5-b]indoles (2) and 11H-tetrazolo[4,5-b]pyridazino[4,5-b]indoles (3) from 4-hydrazino-5H-pyridazino[4,5-b]indoles (1) , as well as the synthesis of 1,2,4-triazolo[3,4-f]-1,2,4-triazino-[4,5-a]indoles (10) from 2-indolecarbohydrazide (4) . Compounds 2 were obtained by acylation of compounds 1 , followed of thermal cyclization and compounds 3 by treating compounds 1 with nitrous acid. The reactions of compound 4 with formic acid or ethyl orthoformiate gave 1,2-dihydro-1-oxo-1,2,4-triazino[4,5-a]indole (6) . Treating this last compound with phosphorus oxychloride or phosphorus pentasulfide, followed by hydrazine, gave 1-hydrazino-1,2,4-triazino-[4,5-a]indole (9) . Acylation of this last compound, followed of cyclization gave compounds 10 . All the compounds were characterized by elemental analysis and ir and 1H-nmr spectra. 相似文献
14.
Z. Arghiani S. M. Seyedi M. Bakavoli H. Eshghi 《Journal of heterocyclic chemistry》2015,52(4):1099-1107
A number of new [1,2,4]triazolo[4,3‐b]pyridazines were prepared by either cyclocondesation of substituted hydrazinopyridazines with orthoesters or oxidative cyclization of their hydrazone analogs in nitrobenzene as an oxidizing agent. A host of other new [1,2,4]triazolo[4,3‐b]pyridazine derivatives were synthesized by sequential treatment of the latter compounds with carbon disulfide and alkyl halides. 相似文献
15.
4-Amino-5-ethyl-4H-1,2,4-triazole-3-thiol was used as a key intermediate for the synthesis of triazolo[3,4-b][1,3,4]thiadiazines, triazolo[4,3-b][1,2,4,5]tetrazines and Schiff’s base via reactions with various hydrazonoyl halides and salicyaldehyde, respectively. Moreover triazolyl-N-N′-triazole derivatives were prepared from reaction of Schiff’s base with various hydrazonoyl halides. The structures of all the newly synthesized heterocyclic compounds were established by considering elemental analysis and spectral data. 相似文献
16.
Ila Sircar 《Journal of heterocyclic chemistry》1985,22(4):1045-1048
The synthesis of novel 6-[4-(1H-imidazol-1-yl)phenyl]-1,2,4-triazolo[4,3-b]pyridazines 8a-f and related compounds is described. Although the intermediate hydrazine derivatives 7 and 9 possess good positive inotropic activity, the fused bicyclic pyridazines 8a-f are significantly less potent than the 3(2H)-pyridazinone 5. Compounds 8a-f are potent but nonselective inhibitors of cardiac phosphodiesterase. 相似文献
17.
V. M. Kisel E. O. Kostyrko V. A. Kovtunenko 《Chemistry of Heterocyclic Compounds》2002,38(9):1130-1133
We propose a convenient preparative method for synthesis of derivatives of novel heterospirane systems with a benzo[5,6][1,2,4]thiadiazino[4,3-b]isoquinoline ring, based on the reaction of 1-(2-bromomethylphenyl)-1-cyclopentanecarbonitrile and 4-(2-bromomethylphenyl)-3,4,5,6-tetrahydro-2H-pyran-4-carbonitrile with o-aminobenzenesulfamide. 相似文献
18.
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
19.
Brigitte Bouteau Jean-Charles Lancelot Max Robba 《Journal of heterocyclic chemistry》1990,27(6):1649-1651
The synthesis of 1,2,4-triazolo[4,3-a] and [2,3-a]pyridines 7, 8 was achieved by cyclization of 2-hydrazino-8-nitropyridine 3a with formic acid. The 4,5,6,7-tetrahydro-1,2,4-triazolo[2,3-a]pyridine 13 and 8-amino-1,2,4-triazolo[2,3-a]pyridine 9 were obtained by catalytic hydrogenation. The reduction of triazolo pyridine 8 using stannous chloride led to the intermediate compound 10 which with acetic anhydride afforded 8-acetylamino-5-chloro-1,2,4-triazolo[2,3-a]pyridine 10a . The structure of the derivatives was determined by 1H-nmr (DMSO-d6). 相似文献
20.
Norton P. Peet 《Journal of heterocyclic chemistry》1984,21(5):1389-1392
The reactions of secondary amines (pyrrolidine, piperidine and morpholine) with 3,4,5-trichloropyridazine ( 4 ) was investigated. With 4 and excess amine, disubstitution occurred in good yield and selectively at positions 3 and 5. Treatment of 4 with 2 equivalents of the amine in ethanol afforded high yields of products resulting from monosubstitution at position 5. 3,4-Dichloro-5-(1-pyrrolidinyl)pyridazine ( 6a ), resulting from 4 and 2 equivalents of pyrrolidine, was converted cleanly to 4-chloro-3-hydrazino-5-(1-pyrrolidinyl)pyridazine ( 8 ) with hydrazine hydrate. Pyridazine 8 was cyclized with formic acid to give a 1:1 complex ( 9 ) of formic acid and 8-chloro-7-(1-pyrrolidinyl)-1,2,4-triazolo[4,3-b]pyridazine ( 13 ). Triazolopyridazine 13 also formed a monohydrate ( 12 ) and a monohydrochloride salt ( 14 ). Catalytic hydrogenation of 9 gave 7-(1-pyrrolidinyl)-1,2,4-triazolo[4,3-b]pyridazine ( 3 ), which was a target compound of this investigation. 相似文献