共查询到20条相似文献,搜索用时 671 毫秒
1.
Treatment of 4-chloro-3-nitropyridine (I) with hydrazine hydrate followed by catalytic reduction gave 3-amino-4-hydrazinopyridine (III). Acid-catalyzed cyclizations of III and subsequent dehydrogenation gave pyrido[3,4- e]- as-triazines (V). Treatment of I with guanidine followed by base-catalyzed cyclization gave 3-aminopyrido[4,3- e]- as-triazine 1-oxide (VII). The 1-oxide function was removed by reduction and subsequent dehydrogenation gave the 3-amino derivative (IX). On treatment with hot alkali VII rearranged to a triazolo[4,5- c]pyridine (X). The ultraviolet and nmr spectra of derivatives of the title ring systems are reported. 相似文献
2.
3-Hydrazino-7-methyl-5-phenyl-5 H-pyrazolo[3,4- c]- as-triazine 1 underwent ring closure and/or condensation reaction with formic acid, acetic acid, acetic anhydride and benzoyl chloride to afford 1 H-pyrazolo-[3,4- d]- s-triazolo[3,4- c]- as-triazines 2, 5 and 7a and/or N-acyl derivatives 3, 4 and 6 . N-Acyl derivatives 3 and 6 underwent cyclisation reaction on treatment with phosphoryl chloride to give 5 and 7a . 3-Methyl-1-phenyl-8-aryl-1 H-pyrazolo[3,4- e]- s-triazolo[34,- c]- as-triazines 7 were also prepared by the reaction of the hydrazono derivatives 8 wit thionyl chloride. On treatment of 1 with nitrous acid gave the 8 H-pyrazolo[3,4- e]tetrazolo-[5,1- c]- as-triazine 9 . Compound 1 underwent ring closure with carbon disulphide or ethyl chloroformate to 1,7-dihydro-8 H-pyrazolo[3,4- e]- s-triazolo[3,4- c]- as-triazine derivatives 10 and 12 . Reaction of 1 with ethyl acetoacetate or acetylacetone gave 3-pyrazolo derivatives 13 and 14 . 相似文献
3.
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
4.
The synthesis of 11H-1,2,4-triazolo[4,3-b]pyridazino[4,5-b]indoles,11H-tetrazolo[4,5-b]pyridazino[4,5-b]indoles and 1,2,4-triazolo[3,4-f]-1,2,4-triazino[4,5-a]indoles
This paper describes the synthesis of the previously unknown 11 H-1,2,4-triazolo[4,3- b]pyridazino[4,5- b]indoles (2) and 11 H-tetrazolo[4,5- b]pyridazino[4,5- b]indoles (3) from 4-hydrazino-5 H-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
5.
The reaction of 2,6-dichloroquinoxaline 4-oxide 4 with methylhydrazine gave 6-chloro-2-(1-methylhydrazino)quinoxaline 4-oxide 5, whose reaction with dimethyl acetylenedicarboxylate or 2-chloroacrylonitrile resulted in the 1,3-dipolar cycloaddition reaction to afford 7-chloro-3,4-bismethoxycarbonyl-1-methyl-1,2-dihydropyridazino[3,4- b]quinoxaline 6 or 6-chloro-3-hydroxymethylene-1-methyl-2,3-dihydro-1 H-pyrazolo[3,4- b] quinoxaline hydrochloride 7, respectively. 相似文献
6.
Reaction of 4-chloro-2-methyl-5-(1-methylhydrazino)-3(2 H)-pyridazinone ( 1 ) with carbon disulfide followed by alkylation yielded 2-alkylthio-4 H-pyridazino[4,5- e][1,3,4]thiadiazine derivatives 2 . Oxidative cyclization of 5-(4-substituted 1-methylthiosemicarbazido)-3(2 H)-pyridazinone derivatives 4 with N-bromosuccinimide also gave 2-substituted amino-4 H-pyridazino[4,5- e][1,3,4]thiadiazine derivatives 5 . Heating of 2 and 5 resulted in ring contraction to afford the corresponding pyrazolo[3,4- d]pyridazine derivatives 6, 7 via sulfur extrusion. A possible mechanism for the desulfurization reaction is discussed, comparing with a structural difference between a type of pyridazino[4,5- e][1,3,4]thiadiazine ( 2,5 ) and another one ( 9,11,13,15 ). 相似文献
7.
The deoxygenated derivative of 3-azidobenzo- as-triazine 1-oxide (II) exists in solution predominantly as 3-azidobenzo- as-triazine form (IVa) but in the crystalline state as tetrazolo[5,]- c]-benzo- as-triazine (IVb), a new fused heteroaromatie ring system. With the pyrido[2,3- e]- as-triazine derivatives, however, both 3-azidopyrido[2,3- e]- as-triazine (X) and pyrido[2,3- e] tetra-zolo[5,1- e]- as-triazine (XI) can be isolated in crystalline form, and these are interconvertible. Another new ring system, the pyrido[2,3- e] triazolo [3,4- c]- as-triazine (XVII) and its derivatives has also been synthesized. 相似文献
8.
A series of pyrido[3,2- e]- as-triazines (VI) was prepared via acid-catalyzed cyclization of suitable 2-substituted 3-aminopyridines obtained by reduction of the corresponding 3-nitro-pyridines. Cyclization of 3-amino-2-hydrazinopyridines (III) with triethyl orthoformate and hydrochloric acid, or cyclodehydration of 2-(2-acetylhydrazino)-3-aminopyridines (IV) with alcoholic hydrogen chloride gave 1,2-dihydropyrido[3,2- e]- as-triazine hydrochloride (V). Mild dehydrogenation with alkaline potassium ferricyanide yielded heteroaromatic pyrido[3,2- e]- as-triazines (VI), for which ultraviolet and nmr spectral data are reported. 相似文献
9.
This paper describes the synthesis of 1-chloro-4-hydrazino-5 H-pyridazino[4,5- b]indole ( 4 ) and some of the triazoles ( 6–8 ), tetrazoles ( 10–11 ), triazolotetrazoles ( 9 ) and bis-tetrazoles ( 12 ) derived from it. All of these were previously unknown compounds. Treating 1,4-dioxo-1,2,3,4-tetrahydro-5 H-pyridazino[4,5- b]indole ( 1 ) with phosphorus oxychloride gave 1,4-dichloro-5 H-pyridazino[4,5- b]indole ( 2 ), which reacts regioselectively with hydrazine to give compound 4 . The reactions of 4 with formic and acetic acids gave 6-chloro-11 H-1,2,4-triazolo[4,3- b]pyridazino[4,5- b]indoles ( 6a-6b ), respectively. Reaction of compound 6a with hydrazine gave 6-hydrazino-11 H-1,2,4-triazolo[4,3–6]-pyridazino[4,5,- b]indole ( 8 ). This with nitrous acid gave 6-azido-11 H-1,2,4-triazolo[4,3- b]pyridazino[4,5- b]-indole ( 9 ). Compound 4 reacted with nitrous acid to give 6-chloro-11 H-tetrazolo[4,5- b]pyridazino[4,5- b]-indole ( 10 ), which gave 1,4-diazydo-5 H-pyridazino[4,5- b]indole ( 12 ), through successive reactions with hydrazine and nitrous acid. All compounds were characterized by elemental analysis, ir and 1H-nmr spectra. 相似文献
10.
Diels-Alder adducts were formed in the lead tetraacetate oxidations of substituted cyclic hydrazides of furan, pyridazine and pyrrole dicarboxylic acids in the presence of 1,3-cyclo-hexadiene or 1,3-cyclopentadiene. The products resulting were furo[3,4- g]pyridazino[1,2- a]-pyridazine-6,10-diones, pyridazino[4,5- g]pyridazino[1,2- a]pyridazine-6,11-diones, and pyrrolo-[3,4- g]pyridazino[1,2- a]pyridazine-6,10-diones, respectively. Some hydrogenations and ring opening reactions were studied. 相似文献
11.
6-Allyl(diallyl, prop-2-yn-1-yl)amino-1-R-pyrazolo[3,4- d]pyrimidin-4(5 H)-ones reacted with iodine to give angularly fused 8-iodomethyl-7,8-dihydro-1-R-imidazo[1,2- a]pyrazolo[4,3- e]pyrimidin-4(6 H)-ones which were treated with sodium acetate to obtain 8-methylidene-1-R-7,8-dihydroimidazo[1,2- a]pyrazolo-[4,3- e]pyrimidin-4(6 H)-ones as a result of elimination of hydrogen iodide. 8-Methylidene-1-R-7,8-dihydroimidazo[1,2- a]pyrazolo[4,3- e]pyrimidin-4(6 H)-ones were converted into 8-methyl-1-R-imidazo[1,2- a]pyrazolo-[4,3- e]pyrimidin-4(5 H)-ones on heating to the melting point. 8-Methylidene-1-phenyl-7,8-dihydroimidazo-[1,2- a]pyrazolo[4,3- e]pyrimidin-4(6 H)-one underwent isomerization into linearly fused 6-methyl-1-phenyl-1,8-dihydro-4 H-imidazo[1,2- a]pyrazolo[3,4- d]pyrimidin-4-one on heating in sulfuric acid. 相似文献
12.
This paper describes the synthesis of 1-hydrazinopyridazino[4,5- b]quinoxaline ( 10 ), tetrazolo[4,3- b]pyridazino[4,5- b]quinoxaline ( 11 ) and some 1,2,4-triazolo[4,3- b]pyridazino[4,5- b]quinoxalines 13 . Starting with 2-ethoxycarbonyl-3-methylquinoxaline 1,4-dioxide ( 1 ), 1,2-dihydro-1-oxopyridazino[4,5- b]quinoxaline ( 5 ) was prepared by three different ways: (a) chlorination of 1 in acetic acid gave 2-ethoxycarbonyl-3-dichloromethylquinoxaline 1,4-dioxide, which reacts with an excess of hydrazine to give about 60% of 5 ; (b) oxidation of 1 with selenium dioxide gave 90% of 2-ethoxycarbonyl-3-formylquinoxaline 1,4-dioxide ( 3 ), which reacts with hydrazine to give 5 (63%); (c) compound 3 was treated with hydrazine to give 1,2-dihydro-1-oxopyridazino-[4,5- b]quinoxaline 1,4-dioxide ( 4 ) (70%), which by reduction with sodium dithionite gave 5 (80%). Compound 5 reacts with phosphorus pentasulfide or the Lawesson reagent to give 1,2-dihydro-1-thiocarbonylpyridazino[4,5- b]quinoxaline ( 9 ), which treated with hydrazine gave 5 (80%). This last compound reacts with nitrous acid to give 11 . Some hydrazones 12 from 10 are described. Heating the aldehyde hydrazones 12a,c,d with dimethylsulfoxide some 1,2,4-triazolo[4,3- b]pyridazino[4,5- b]quinoxalines 13 were obtained. Compound 13a was also obtained in the reaction of 10 with benzoyl chloride. Reaction of 3 with phenylhydrazine gave 1,2-dihydro-1-oxo-2-phenylpyridazino[4,5- b]quinoxaline ( 6 ). Reactions of 5 with acetic anhydride and dimethylsulfate gave, respectively, 1-acetoxypyridazino[4,5- b]quinoxaline ( 8 ) and 1,2-dihydro-1-oxo-2-methylpyridazino-[4,5- b]quinoxaline ( 7 ). All the compounds were characterized by elemental analysis and 1H-nmr spectra. Compounds 5 and 10 showed antihypertensive activity in rats. 相似文献
13.
When dissolved in liquid ammonia 5-chloro-1,2-dihydropyrimido[5,4- e]-1,2,4-triazine ( 1 ) and 5-methoxy-pyrimido[5,4 e]-1,2,4-triazine ( 4 ) quickly convert into 5-aminopyrimido[5,4- e]-1,2,4-triazine ( 2 ). When 2 is kept in liquid ammonia containing an excess of potassium permanganate, 3,5-diaminopyrimido[5,4- e]-1,2,4-triazine ( 5 ) is formed. 相似文献
14.
10-Methyl-7-aryl-7,12-dihydro-6H,8H-chromeno[4,3-b]pyrano[3,4-e]pyridine-6,8-dione derivatives are significant class of compounds and this is critical to develop methods in water using commercially available and non-toxic catalysts. In this paper, an efficient method is introduced for the synthesis of 10-methyl-7-aryl-7,12-dihydro-6H,8H-chromeno[4,3-b]pyrano[3,4-e]pyridine-6,8-dione derivatives. For the synthesis of the desired products, a multicomponent reaction was designed and performed between 4-hydroxycoumarin, an aldehyde, 6-methyl-2H-pyran-2,4(3H)-dione, and ammonium acetate. The products are obtained under green conditions in water in the presence of a catalytic amount of L-proline (10 mol%). The advantage of this method is no need to any toxic solvent, which is critical from the environmental viewpoint. A possible mechanism was suggested, which confirms the role of L-proline in the reaction as the catalyst. 相似文献
15.
Reactions of 6-arylidenehydrazino-1,3-dimethyluracil derivatives with N-bromosuccinimide leading to pyrazolo[3,4- d]pyrimidines, pyrimido[5,4- e]- as-triazines, and pyrimido[4,5- c]pyridazines are described. 相似文献
16.
New organic nitrates. II. Synthesis of 2H-pyrido[2,3-e]-1,3-oxazine-2,4(3H)-diones, 2H-pyrido[4,3-e]-1,3-oxazine-2,4(3H)-diones, 2H-pyrido[4,3-e]-1,3-oxazin-4(3H)-ones, 2H-thieno[2,3-e]-1,3-oxazin-4(3H)-ones and 2H-thieno[3,4-e]-1,3-oxazin-2,4(3H)-diones
The preparation and the physico-chemical characterization of 2 H-pyrido[2,3- e]-1,3-oxazine-2,4(3 H)-diones, 2 H-pyrido[4,3- e]-1,3-oxazine-2,4(3 H)-diones, 2 H-pyrido[4,3- e]-1,3-oxazin-4(3 H)-ones, 2 H-thieno[2,3- e]-1,3-oxazin-4(3 H)-ones and 2 H-thieno[3,4- e]-1,3-oxazine-2,4(3 H)-diones are reported. 相似文献
17.
The synthesis of various 2-methylpyrazolo[4,3- e]- and thiazolo[4,5- e][1,2]thiazine 1,1-dioxide derivatives is described. 相似文献
18.
Novel 4-chlorophenylhydrazono-3-oxo-1,2,3,4-tetrahydropyridazino[3,4- b]quinoxalines 10a-c were synthesized by the cyclization of the α-hydrazonohydrazides 8a-c. The chlorination of 10a with phosphoryl chloride afforded 3-chloro-4-[2-( o-chlorophenyl)hydrazino]pyridazino[3,4- b]quinoxaline 12. 相似文献
19.
The reaction of 7-chloro-4-ethoxycarbonylmethylene-4,5-dihydro-1,2,4-triazolo[4,3- a]quinoxaline 6 with 4-ethoxycarbonyl-1-methyl-1 H-pyrazole-5-diazonium chloride or 4-cyano-1,3-dimethyl-1 H-pyrazole-5-diazonium chloride gave 7-chloro-4-[α-(4-ethoxycarbonyl-1-methyl-1 H-pyrazol-5-ylhydrazono)-ethoxycarbonylmethyl]-1,2,4-triazolo[4,3- a]quinoxaline 8a or 7-chloro-4-[α-(4-cyano-1,3-dimethyl-1 H-pyrazol-5-ylhydrazono)ethoxycarbonylmethyl]-1,2,4-triazolo[4,3- a]quinoxaline 8b , respectively, while the reaction of 7-chloro-4-ethoxycarbonylmethylene-4,5-dihydrotetrazolo[1,5- a]quinoxaline 7 with 4-ethoxycarbonyl-1-methyl-1 H-pyrazole-5-diazonium chloride or 4-cyano-1,3-dimethyl-1 H-pyrazole-5-diazomum chloride provided 7-chloro-4-[α-(4-ethoxycarbonyl-1-methyl-1 H-pyrazol-5-ylhydrazono)ethoxycarbonylmethyl]tetrazolo[1,5- a]quinoxaline 9a or 7-chloro-4-[α-(4-cyano-1,3-dimethyl-1 H-pyrazol-5-ylhydrazono)ethoxycarbonylmethyl]tetrazolo[1,5- a]quinoxaline 9b , respectively. Compounds 8a,b and 9a,b showed the tautomeric equilibria between the hydrazone imine C and diazenyl enamine D forms in dimethyl sulfoxide and/or trifluoroacetic acid, and the effects of solvent and temperature on the tautomer ratios of C to D were studied by the nmr measurements in a series of mixed trifluoroacetic acid/dimethyl sulfoxide media (compounds 8a,b and 9a,b ) and at various temperatures (compounds 8a,b ). 相似文献
20.
Reaction of 5-arylazo-6-arylidenehydrazino-1,3-dimethyluracils (II), prepared by the treatment of 6-aryl-idenehydrazino-1,3-dimethyluracils (I) with diazotized arylamines, with dimethylformamide dimethylacetal resulted in the formation of pyrimido[5,4- e]- as-triazine (V) system, while the thermolysis of II resulted in the formation of purine (X), v-triazolo[4,5- d]pyrimidine (XII), and pyrazolo[3,4- d]pyrimidine (XIV, XIX) systems in lieu of the expected V. Reasonable mechanisms have been proposed for the formation of the various ring systems in these reactions. 相似文献
|