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1.
In this paper, a straightforward and valid three-component Michael/cyclization reaction of (E)-1-methyl-3-(arylidene)piperidin-4-ones, 2-(sulfonyl)acetonitriles, and aromatic aldehydes was explored for the preparation of potentially biologically active 3-(sulfonyl)-5,6,7,8-tetrahydro-4H-pyrano[3,2-c]pyridines under mild reaction conditions. More diverse 3-(sulfonyl)-5,6,7,8-tetrahydro-4H-pyrano[3,2-c]pyridine derivatives were constructed in satisfactory yields (up to 97%). The chemical structure of newly synthesized 3-(sulfonyl)-5,6,7,8-tetrahydro-4H-pyrano[3,2-c]pyridines were identified with 1H-NMR, 13C-NMR, and mass spectrometry analysis. The recommendable method features a simple and direct workup, easy access to initial materials, high atom utilization efficiency, high final product yields, and a wide range of substrate adaptability.  相似文献   

2.
7-Acetyl-2,3,5,6,7,8-hexahydro-6-hydroxy-1,6-dimethyl-3-thioxo-8-phenyl(heteryl)isoquinoline-4-carbonitriles were obtained by reaction of 2,4-diacetyl-5-hydroxy-5-methyl-3-phenyl(heteryl)cyclohexanones with cyanothioacetamide. Structure of 7-acetyl-5,6,7,8-tetrahydro-6-hydroxy-1,6-dimethyl-3-methylthio-8-phenylisoquinoline-4-carbonitrile was proved by X-ray diffraction method.  相似文献   

3.
The cycloadducts of menthofuran with acylbromoacetylenes, (3-bromo-1,6-dimethyl-5,6,7,8-tetrahydro-2H-2,4a-epoxynaphthalen-4-yl)(aryl)methanones, rearrange (CHCl3, reflux, 1 h) to 2-(2-acylethyl)benzofurans (along with the expected 2-bromo-3-hydroxy-4,7-dimethyl-5,6,7,8-tetrahydronaphthalene-1-yl)(aryl)methanones) via 2-acylethynylmenthofurans, thus indicating the exceptionally mild and rapid transfer of four hydrogens from a cyclohexane ring to a triple bond through the furan moiety in the key intermediate 2-acylethynylmenthofuran.  相似文献   

4.
2-Amino-4-[3-methyl-3-(5,6,7,8-tetrahydro-2-naphthyl)cyclobutyl]thiazole was synthesized by reaction of 1-methyl-1-(5,6,7,8-tetrahydro-2-naphthyl)-3-chloroacetylcyclobutane with thiourea in ethanol, and its subsequent transformations afforded new derivatives which were tested in vitro for antibacterial activity against some bacteria using the disk diffusion technique.__________From Zhurnal Organicheskoi Khimii, Vol. 40, No. 12, 2004, pp. 1861–1865.Original English Text Copyright © 2004 by Koparr, Cansz, Ahmedzade.The original article was submitted in English.  相似文献   

5.
The targeted synthesis of 2-(methylsulfanyl)-6-(furan-2-yl)-4(3H)-selenoxo -pyrimidine-5-carbonitrile failed due to the formation 1-methyl-2-methylsulfanyl-6-oxo -4-(furan-2-yl)-1,6-dihydropyrimidine-5-carbonitrile. A new series of 5,6,7,8-tetrahydro-1-benzo thieno[2,3-d]pyrimidine-4-yl substituted selanyl derivatives were prepared by the reaction of sodium diselenide with 4-chloro-5,6,7,8-tetrahydro-1-benzothieno[2,3-d]pyrimidine followed by the reaction with chloroacetic acid derivatives such as ethyl chloroacetate, chloroacetamide or chloroacetonitrile. Hydrazinolysis of ethyl (5,6,7,8-tetrahydro-1-benzothieno[2,3-d]pyrimidine- 4-ylselanyl)acetate with hydrazine hydrate gave the corresponding hydrazino derivative. The latter reacted with ethyl acetoacetate, acetylacetone, diethyl malonate, ethoxymethylenemalononitrile or ethyl 2-cyano-3-ethoxyacetate to afford 5-methyl-2-[2-(5,6,7,8-tetrahydro-1-benzothieno [2,3-d]pyrimidine-4-ylselanyl)acetyl]-2,4-dihydropyrazol-3-one, 1-(3,5-dimethylpyrazol-1-yl)-2- (5,6,7,8-tetrahydro-1-benzothieno[2,3-d]pyrimidin-4-ylselanyl)ethanone, 1-[2-(5,6,7,8-tetrahydro -1-benzothieno[2,3-d]pyrimidine-4-ylselanyl)acetyl]-2,4-dihydropyrazolidine-3,5-dione and 5-Amino-1-[2-(5,6,7,8-tetrahydro-1-benzothieno[2,3-d]pyrimidin-4-ylselanyl)acetyl]-1H-pyrazol -4-yl substituted carbonitrile or ethyl carboxylate, respectively. The structure of the novel compounds was confirmed by spectroscopic tools (IR, 1H NMR 13C NMR and mass spectra) and elemental analysis.  相似文献   

6.
The five-component reaction of ethyl 2-[(2-oxopropyl)sulfanyl]acetate, aromatic aldehydes, and ammonium acetate affords two diastereomers of 5,7-diaryl-5,6,7,8-tetrahydro-1H-pyrido[3,4-b][1,4]thiazin-2(3H)-ones via a novel tandem Mannich-enamine-substitution sequence. Presumably, they are generated from ethyl 2-[(4-oxo-2,6-diaryl-3-piperidinyl)sulfanyl]acetates. During the formation of the trans-5,7-diaryl-5,6,7,8-tetrahydro-1H-pyrido[3,4-b][1,4]-thiazin-2(3H)-ones from ethyl 2-[(4-oxo-2,6-diaryl-3-piperidinyl)sulfanyl]acetates, the configuration at the carbon bearing an aryl group adjacent to the enamide CC double bond is inverted via ring opening and closure. When o-substituted benzaldehydes were employed in this reaction, 5,7-diaryl-5,6-dihydro-1H-pyrido[3,4-b][1,4]thiazin-2(3H)-ones were obtained via air oxidation, along with trans-5,7-diaryl-5,6,7,8-tetrahydro-1H-pyrido[3,4-b][1,4]-thiazin-2(3H)-ones.  相似文献   

7.
Three-component condensation of dimedone with phenylglyoxal hydrate and malononitrile gave a polyfunctional 5,6,7,8-tetrahydro-4H-chromene derivative, 2-amino-4-benzoyl-7,7-dimethyl-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile, which reacted with ammonium acetate to produce pyrrolo[3,4-c]quinoline ring system. Reactions of the condensation product with primary and secondary amines and hydroxylamine hydrochloride afforded polysubstituted pyrroles, whereas the reaction with hydrazine hydrate led to 3-amino-6-phenylpyridazine-4-carbonitrile.  相似文献   

8.
The synthesis of 1-chloro-4,5,6,7-tetrahydrobenzo[c]-4-thiophenone and 1-chloro-5,6,7,8-tetrahydro-4H-cyclohepta[c]-4-thiophenone was accomplished by the cyclization of the acid chlorides of -(2,5-dichloro-3-thienyl)butyric acid and -(2,5-dichloro-3-thienyl)valeric acid, respectively, to 1,3-dichloro-4,5,6,7-tetrahydrobenzo[c]-4-thiophenone and 1,3-dichloro-5,6,7,8-tetrahydro-4H-cyclohepta[c]-4-thiophenone and by partial dehalogenation of the latter by heating with copper metal in propionic acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1358–1360, October, 1971.  相似文献   

9.
Isomeric 1- and 3-isoquinolinols (11 and 12) when activated in CF(3)SO(3)H-SbF(5) acid system undergo selective ionic hydrogenation with cyclohexane to give 5,6,7,8-tetrahydro-1(2H)- and 5,6,7,8-tetrahydro-3(2H)-isoquinolinones (22 and 27). Under the influence of aluminum chloride similar products were also obtained along with 3,4-dihydro-1(2H)- and 1,4-dihydro-3(2H)-isoquinolinones (23 and 28), respectively. Compounds 11 and 12 also condense with benzene in the presence of aluminum halides, under mild conditions, to give 3,4-dihydro-3-phenyl-1(2H)- and 1,4-dihydro-1-phenyl-3(2H)-isoquinolinones (24 and 29), respectively. Prolonged reaction time or catalysis under strongly acidic HBr-AlBr(3) provides an alternative reaction pathway to yield 5,6-dihydro-6,8-diphenyl-1(2H)- and 5,6,7,8-tetrahydro-6,8-diphenyl-3(2H)-isoquinolinones (25 and 30), respectively. Products 24 and 29 were also found to revert back to 11 and 12 in the presence of aluminum halides in o-dichlorobenzene. The mechanism of these intriguing reactions, which involves superelectrophilic dicationic intermediates, is discussed.  相似文献   

10.
Sterically hindered 2,4-disubstituted 3-(5-tetrazolyl)pyridines were synthesized from corresponding nicotinonitriles using microwave technology. 2-Methylnicotinonitriles were converted into the 2-azidomethyl-3-cyanopyridines via 2-hydroxymethyl and 2-chloromethyl derivatives. Intramolecular [3+2] cycloaddition of an heteroaromatic cyano group to side azido group was carried out to form a novel heterocyclic system containing a (tetrazolo)azaisoindole unit. Condensation of the 2-methylnicotinonitriles and aldehydes gave rise to the corresponding 2-vinyl derivatives, which were then transformed into novel heterocyclic system (5,6-dihydrotetrazolo[5,1-f]-1,6-naphthyridine) by intramolecular N-alkylation reaction of tetrazole ring with olefinic fragment. The 3-(5-tetrazolyl)pyridines obtained were alkylated to give the various N- and C-benzyl derivatives as well as acylated to afford the 3-(1,3,4-oxadiazol-2-yl)pyridines in good yields. A majority of above-mentioned reactions was carried out under microwave irradiation.  相似文献   

11.
Substituted 2-aminobenzo[b]pyrans were synthesized by three-component condensation of aromatic aldehydes, cyanoacetic acid derivatives, and cyclic 1,3-diketones. The molecular and crystal structure of 2-amino-3-(2-methoxyethoxycarbonyl)-4-(2-nitrophenyl)-5-oxo-5,6,7,8-tetrahydro-4H-benzo[b]pyran was established by X-ray diffraction analysis.  相似文献   

12.
The syntheses of 4-(benzo[b]furan-3-yl)piperidines, 4-(benzo[b]furan-2-yl)piperidines and 4-(benzo[b]thiophen-3-yl)piperidines with 5-HT2 antagonist activity are described. Reaction of 1-acetyl-4-(2,4-difluorobenzo-yl)piperidine 2 with methyl glycolate gave methyl 6-fluoro-3-(1-acetylpiperidin-4-yl)benzo[b]furan-2-carboxylate 3 , which was converted to 2-[2-[4-(benzo[b]furan-3-yi)piperidin-1-yl]ethyl-5,6,7,8-tetrahydro-1,2,4-triazolo-[4,3-a]pyridin-3(2H)-one hydrochloride 9 . Analogous benzo[b]furans 17a-d and benzo[b]thiophenes 10a,b and 18a were prepared by a similar method. Cyclization of 4-fluoro-2-(4-pyridinylmethoxy)acetophenones 20a,b afforded 4-(benzo[b]furan-2-yl)pyridines 21a,b , which were converted to 2-[2-[4-(benzo[b]furan-2-yl)-piperidin-1-yl]ethyl-5,6,7,8-tetrahydro-1,2,4-triazolo[4,3-a]pyridin-3(2H)-one hydrochlorides 24a,b. Among them, benzo[b]furans 9 and 17a,d and benzo[b]thiophenes 10 and 18a showed potent 5-HT2 antagonist activity in vitro.  相似文献   

13.
Methods have been developed for the synthesis of new 8-amino-3-benzyl-5-(morpholin-4-yl)-1,2,3,4-tetrahydropyrimido[4′,5′: 4,5]thieno[2,3-c][2,7]naphthyridine starting from 7-benzyl-3-chloro-1-(morpholin-4-yl)-5,6,7,8-tetrahydro-2,7-naphthyridine-4-carbonitrile. 8-Hydrazinyl-3-benzyl-5-(morpholin-4-yl)-1,2,3,4-tetrahydropyrimido[4′,5′: 4,5]thieno[2,3-c][2,7]naphthyridine has been converted to isomeric pentacyclic structures with a triazole ring fused through the [c] side of the pyrimidine ring, and their Dimroth rearrangement has been accomplished in both acidic and basic media. New heterocyclic systems containing pyrrolo[1,2-a]pyrimidinone and pyrimido[1,2-a]azepinone fragments were obtained on the basis of the thieno-[2,3-c][2,7]naphthyridine derivative.  相似文献   

14.
Regioselective alkylation of 2-alkyl-5,6,7,8-tetrahydro-3H-cycloheptimidazol-4-one (1) and 2-alkyl-3H-cycloheptimidazol-4-one (2) was investigated. 3-[2'-(1-tert-Butyl-1H-tetrazol-5-yl)biphenyl-4-ylmethyl]-2-propyl-5,6,7,8-tetrahydro-1H-cycloheptimidazol-4-one (6) was preferentially obtained under the conditions by using NaH in DMF or THF. On the other hand, 3-[2'-(1-tert-butyl-1H-tetrazol-5-yl)biphenyl-4-ylmethyl]-2-propyl-5,6,7,8-tetrahydro-3H-cycloheptimidazol-4-one (5), the synthetic intermediate compound of Pratosartan, was obtained selectively in the presence of n-Bu(4)NBr in toluene by using aqueous sodium hydroxide as a base. In this reaction, it was found that the concentration of the alkaline solution influences its regioselectivity. This selectivity was observed even for aldehyde and ester derivatives.  相似文献   

15.
Michael reactions of isopropylidenemalononitrile with cyanothioacetamide (in the presence of 4-methoxyphenacyl bromide), cyclohexane-1,3-dione, and 4-hydroxycoumarin, gave 6-amino-2-(4-methoxy-benzoylmethylsulfanyl)-4,4-dimethyl-1,4-dihydropyridine-3,5-dicarbonitrile, 2-amino-4,4-dimethyl-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile, and 2-amino-4,4-dimethyl-5-oxo-4H,5H-pyrano[3,2-c]-chromene-3-carbonitrile, respectively. In the reaction of isopropylidenemalononitrile with cyanoacetamide, only dimerization product of the former, 2-amino-4,6,6-trimethylcyclohexa-2,4-diene-1,1,3-tricarbonitrile, was isolated. Its structure was proved by X-ray analysis.  相似文献   

16.
Abstract

The synthesis of acetic 2-{[1-methyl-2-(4-oxo-5,6,7,8-tetrahydro-4H-benzo [4,5]-thieno [2,3-d] [1,3-oxazin-2-yl)ethylidene]amino}-4,5,6,7-tetrahydrohenzo[b]thiophene ?3-carboxylic acid anhydride 5 and 2-(oxopropyl)-5,6,7,8-tetrahydro-4H-benzo-[4,5] thieno[2,3-d][1,3]oxazin-4-one 7, has been achieved in three steps from ethyl 2-amino-4,5,6,7-tetrahydrobenzo(b]thiophene-3-carboxlate 1 via the reaction with ethyl acetoacetate followed by hydrolysis and acetic anhydride-induced cyclization. The 2-substituent in compound 5 has two functional groups i.e. active methylene and acid anhydride which are suitably located for intramolecular transformation. Thermal and/or base catalyzed intramolecular cyclization of 5 afforded 2-(4-acetoxy-(hydroxyl)-2-methyl-5,6,7,8-tetrahydrobenzo[4,5] thieno[2,3-b]pyridin-3-yl)-5,6,7,8- tetrahydro-4H-benzo[4,5]thieno[2,3-d] [1,3]oxazin-4-one 10 and 9 respectively. Treatment of 5 with hydrazine hydrate, aromatic and/or heterocyclic amines induced the same intramolecular cyclization with a concomitant oxazine-pyrimidine interconversion to give 3-amino(aryl or heteryl)-2-(4-hydroxy-5,6,7,8-tetrdhydrobenzo-[4,5]thieno[2,3-b]pyridin-3-yl)-3,4,5,6,7,8-hexahydrobenzo[4,5] thieno[2,3-d] pyrimid in-4-one 11–14 respectively.  相似文献   

17.
The oxidation of methyl (4-acetylphenyl)carbamate with selenium dioxide in dioxane–water (30: 1) gave methyl [4-(oxoacetyl)phenyl]carbamate whose condensation with ethyl acetoacetate or diethyl malonate and hydrazine hydrate afforded ethyl 3-methyl-6-[4-(methoxycarbonylamino)phenyl]pyridazine-4-carboxylate and methyl {4-[5-(hydrazinecarbonyl)-6-oxo-1,6-dihydropyridazin-3-yl]phenyl}carbamate, respectively. The reaction of methyl [4-(oxoacetyl)phenyl]carbamate with o-phenylenediamine in dimethylformamide–ethanol on heating led to the formation of methyl [4-(quinoxalin-2-yl)phenyl]carbamate. Methyl {4-(5,7-dioxo- 4,4a,5,6,7,8-hexahydropyrimido[4,5-c]pyridazin-3-yl)phenyl}carbamate and methyl {4-(5-oxo-7-sulfanylidene- 4,4a,5,6,7,8-hexahydropyrimido[4,5-c]pyridazin-3-yl)phenyl}carbamate were synthesized by reactions of methyl [4-(oxoacetyl)phenyl]carbamate with barbituric and thiobarbituric acids, respectively, and hydrazine hydrate in the presence of zirconyl chloride octahydrate at room temperature.  相似文献   

18.
Condensation of 3-(3,5-dimethylphenyl)-2-oxocyclopentanecarboxamide (11) with oxalyl chloride and condensation of ethyl 2-benzylamino-5-methyl-3-phenylcyclopent-1-enecarboxylate (17a) with trimethylsilyl isothiocyanate gave 7-(3,5-dimethylphenyl)-6,7-dihydro-5H-cyclopenta[e][1,3]oxazine-2,4-dione (12) and 1-benzyl-5-methyl-7-phenyl-2-thioxo-1,2,3,5,6,7- hexahydrocyclopentapyrimidin-4-one (18a), respectively. Acid catalyzed ring-closure of 6-(4-methyl-1-phenylpent-3-enyl)-2-thioxo-2,3-dihydro-1H-pyrimidin-4-one (26) and radical mediated ring-closure of 1,3-bis(benzyloxymethyl)-5-bromo-6-(1-phenylbut-3-enyl)-1H-pyrimidine-2,4- dione (32a) gave 5,5-dimethyl-8-phenyl-5,6,7,8-tetrahydro-1H-quinazoline-2,4- dione (28) and 1,3-bis(benzyloxymethyl)-5-methyl-7-phenyl-1,5,6,7- tetrahydrocyclopentapyrimidine-2,4-dione (33), respectively. Annelated emivirine analogues 7-(3,5-dimethylphenyl)-1- ethoxymethyl-1,5,6,7-tetrahydrocyclopentapyrimidine-2,4-dione (4), 1-ethoxymethyl-5,5-dimethyl-8-phenyl-5,6,7,8-tetrahydro-1H-quinazoline- 2,4-dione (5) and 1-ethoxymethyl-5-methyl-7-phenyl-1,5,6,7- tetrahydrocyclopentapyrimidine-2,4-dione (6) were obtained in few steps from 12, 28 and 18a/33, respectively. These new analogues can be considered as conformationally locaTed analogues of emivirine. However, the compounds 4 6 showed lower activities against HIV-1 than emivirine and it is concluded that the locked conformation disfavours activity against HIV-1.  相似文献   

19.
Treatment of 5,6,7,8-tetrahydro-5,8-methanoisoquinoline N-oxide ( 2 ) with fuming nitric acid afforded 3-nitro-5,6,7,8-tetrahydro-5,8-methanoisoquinoline N-oxide ( 3 ), an example of formation of an α-nitropyridine N-oxide derivative by nitration of N-oxides. Further reaction of 3 resulted in deoxygenation giving 3-nitro-5,6,7,8-tetrahydro-5,8-methanoisoquinoline ( 4 ). No aromatic nitration was observed by similar treatment of 5,6,7,8-tetrahydro-5,8-methanoisoquinoline ( 1 ) or 5,6,7,8-tetrahydroisoquinoline N-oxide ( 11 ). Some other aromatic substitutions with 1 and 2 were caried out to obtain mainly the 3-substituted derivatives. Significant mutagenicity of 3 is briefly reported.  相似文献   

20.
An isomerization-ring-closing metathesis (RCM) strategy afforded N-substituted 4H-1,4-benzoxazines from the protected N-allyl-2-(allyloxy)anilines. In addition, RCM was used to synthesize the N-substituted, 8-membered benzo-fused heterocycles from the respective diallyl compounds: 1,2,5,6-tetrahydro-1,6-benzodiazocine, 5,6-dihydro-2H-1,6-benzoxazocine, 5,6,9,10-tetrahydropyrido[2,3-b][1,4]diazocine and 5,6-dihydro-2H-1,6-benzothiazocine 1,1-dioxide. The isomerization-RCM approach also afforded the 7-membered ring system, 2,5-dihydro-1,5-benzothiazepine 1,1-dioxide, from the protected N-allyl-2-(allylsulfonyl)aniline. Furthermore, the structure of 1,6-bis[(4-methylphenyl)sulfonyl]-1,2,5,6-tetrahydro-1,6-benzodiazocine was confirmed by a single crystal X-ray determination.  相似文献   

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