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1.
A concise synthesis of some new classes of heterocycles (4-aryl-11-oxo-1,2,3,11-tetrahydro-1,3a-diaza-cyclopenta[a]anthracen-6-carbonitriles and 5-aryl-12-oxo-1,3,4,12-tetrahydro-2H-1,4a-diazabenzo[a]anthracene-7-carbonitriles) has been developed by the ring transformation of suitably functionalized 2H-pyran-2-one with α-oxoketene cyclic aminals to intermediates (8-aroyl-5-aryl-2,3-dihydro-1H-imidazo[1,2-a]pyridine-7-ylidene)-acetonitriles and (9-aroyl-6-aryl-1,2,3,4-tetrahydropyrido[1,2-a]pyrimidin-8-ylidene)-acetonitriles) followed by their photocyclization either in CHCl3 or acetonitrile. This reaction was further explored for the synthesis of methyl 4-aryl-11-oxo-1,2,3,11-tetrahydro-1,3a,9-triaza-cyclopenta[a]anthracene-6-carboxylate, 4-aryl-11-oxo-1,2,3,11-tetrahydro-1,3a,9-triaza-cyclopenta[a]anthracene-6-carbonitriles, 5-aryl-12-oxo-1,3,4,12-tetrahydro-2H-1,4a,10-triazabenzo[a]anthracene-7-carbonitriles, 4-aryl-10-oxo-1,2,3,10-tetrahydro-9-thia-1,3a-diazadicyclopenta[a,g]naphthalene-6-carbonitriles and 5-aryl-11-oxo-1,3,4,11-tetrahydro-2H-10-thia-1,4a-diazacyclopenta[b]phenanthrene-7-carbonitriles from the similar reactions. 相似文献
2.
Ethyl 4-methyl-2-oxo-7-phenylthio-2,3,6,7-tetrahydro-1H-1,3-diazepine-5-carboxylate and/or ethyl 6-methyl-2-oxo-4-(phenylthiomethyl)-1,2,3,4-tetrahydropyrimidine-5-carboxylate were obtained in the reaction of ethyl 4-chloromethyl-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate with PhSNa or PhSK with or without PhSH, depending on the reagent ratio, reaction time, or temperature, as a result of ring expansion and/or nucleophilic substitution. The reaction pathway was affected strongly by the basicity-nucleophilicity of the reaction media. The results obtained were confirmed by reactions of 4-mesyloxymethyl-6-methyl-5-tosyltetrahydropyrimidin-2-one with PhSNa/PhSH and ethyl 4-chloromethyl-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate with NaCN/HCN or NaCH(COOEt)2/CH2(COOEt)2. 相似文献
3.
A number of 5-amino-2,3-dihydro-lH-1,4-benzodiazepines (II) have been prepared from the reaction of 5-methylmercapto-2,3-dihydro-1H-1,4-benzodiazepine (I) with amines. Another alternate approach based on the cyclodehydration of the ureic compounds (IV) was unsuccessful. The synthesis of I was accomplished by methylation of the 1,2,3,4-tetrahydro-5H-5-thioxo-1,4-benzodiazepine (VI) with dimethyl sulfate in methanol-dioxane. Another attempted method for the synthesis of I is also presented. J. Heterocyclic Chem., 14, 985 (1977) 相似文献
4.
The reaction of 2-chloro-3-oxo-3,4-dihydro-2H-1,4-benzothiazines with ‘push-pull’ enamines was investigated. The reaction with the enamines occurs at the β-carbon atom in the presence of a small excess of triethylamine. As a result, a set of 3-oxo-3,4-dihydro-2H-1,4-benzothiazin-2-yl derivatives of 1,3-dicarbonyl compounds and benzothiazinone spiro derivatives was prepared. On acidic hydrolysis of ethyl 2-ethyl-3-(methylimino)-2-(3-oxo-3,4-dihydro-2H-1,4-benzothiazin-2-yl)butanoate, a new rearrangement affording ethyl 11-ethyl-2,3-dimethyl-4-oxo-2,3,4,5-tetrahydro-1H-2,5-methano-6,1,3-benzothiadiazocine-11-carboxylate was discovered. A plausible mechanism and factors influencing the course of the reaction are discussed. 相似文献
5.
A series of novel N-benzylcarboxamide derivatives of bicyclic compounds, 3,4-dihydropyrido[3,2-f][1,4]oxazepin-5(2H)-one and 2,3,4,5-tetrahydro-6H-pyrido[2,3-b][1,5]oxazocin-6-one, were synthesized by cyclization of N-benzyl-2-chloro-N-(2-hydroxyethyl)- [and -(3-hydroxypropyl)-] nicotinamides, respectively. Atropisomerism was observed in 5-[3,5-bis(trifluoromethyl)benzyl]-7-phenyl-2,3,4,5-tetrahydro-6H-pyrido[2,3-b][1,5]oxazocin-6-ones due to steric hindrance of the carboxamide moiety and restriction of its rotation. Cyclization of N-[3,5-bis(trifluoromethyl)benzyl]-2-chloro-N-[(2S)-3-hydroxy-2-methylpropyl]-5-methyl-4-phenylnicotinamide gave (3S)-5-[3,5-bis(trifluoromethyl)benzyl]-3,8-dimethyl-7-phenyl-2,3,4,5-tetrahydro-6H-pyrido[2,3b][1,5]oxazocin-6-one, which exists predominantly in the thermodynamically stable aR-conformer in CDCl3. This compound showed excellent NK1-antagonistic activity with IC50 value (in vitro inhibition of [125I]-Bolton-Hunter-substance P binding in human IM-9 cells) of 0.47 nM, which is ca. 200-fold more potent than that of its enantiomer, indicating that the atropisomer chirality affects NK1-receptor recognition. 相似文献
6.
2,3,4,5-Tetrasubstituted 4,5-dihydro-3H-1,4-benzodiazepines were synthesized in one-pot by a new sequential Ugi 4CC/Staudinger/aza-Wittig reaction, starting from easily accessible o-azidobenzaldehyde, α-amino ketone hydrochloride, isocyanide and carboxylic acid. 相似文献
7.
When treated with an excess of MeONa in DMF, 5-benzylsulfonyl-3-chloro-4-methoxycarbonylaminoisothiazole undergoes cyclization into 3-methoxy-5-oxo-6-phenyl-5,6-dihydro-4H-isothiazolo[5,4-b]-1,4-thiazine 7,7-dioxide, the first representative of a new heterocyclic system. The starting 5-benzylsulfonyl-3-chloro-4-methoxycarbonylaminoisothiazole was prepared by the reaction of 5-benzylsulfonyl-4-carbamoyl-3-chloroisothiazole with PhI(OAc)2 in methanol. 相似文献
8.
A general synthesis of new alkyl 4-alkyl-2-hydroxy-3-oxo-3,4-dihydro-2H-1,4-benzoxazine-2-carboxylate peptidomimetic building blocks from the corresponding alkyl 3-oxo-3,4-dihydro-2H-1,4-benzoxazine-2-carboxylates through carbanion oxidation is described. 相似文献
9.
The [Cp∗IrCl2]2/K2CO3 catalyzed hydrogen transfer N-heterocyclization on a series of anilino alcohols has been investigated. The catalyst (20% loading) converts anilino alcohols to 1,2,3,4-tetrahydroquinoxalines and 2,3,4,5-tetrahydro-1H-benzo[b][1,4]diazepines in 30-84% isolated yield. 相似文献
10.
O. V. Gulyakevich K. A. Krasnov A. L. Mikhal'chuk A. A. Akhrem 《Chemistry of Heterocyclic Compounds》2004,40(8):1070-1076
5-(2-Acetyl-1,2,3,4-tetrahydro-1-isoquinolyl)-6-hydroxy-2-methylthio-1,4-dihydro-4-pyrimidinones have been obtained by the interaction of 3,4-dihydroisoquinolines with 2-methylthio-4-oxo-1,4-dihydro-6-pyrimidinyl acetate. It was shown that N,O-methyl derivatives are formed in interaction of the obtained products with diazomethane. 相似文献
11.
Iryna O. LebedyevaVictor V. Dotsenko Vladimir V. Turovtsev Sergey G. KrivokolyskoV'yacheslav M. Povstyanoy Mikhaylo V. Povstyanoy 《Tetrahedron》2012,68(47):9729-9737
3-Cyanopyridine-2(1H)-thiones have been shown to react with Biginelli-type ethyl 4-aryl-6-(bromomethyl)-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylates upon heating in DMF giving rise to ethyl 4-aryl-6-{[(3-cyanopyridin-2-yl)thio]methyl}-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylates. The latter upon treatment with an excess of NaH or t-BuOK in boiling DMF undergo a tandem Thorpe-Ziegler-type heterocyclization to give pyrido[3″,2″:4′,5′]thieno[2′,3′:5,6]pyrido[4,3-d]pyrimidine derivatives in good yields. Selected compounds were tested for antibacterial and antifungal activity. 相似文献
12.
Velanganni Paul Alex Raja 《Tetrahedron》2006,62(20):4892-4899
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
13.
Sequential Ugi reaction between p-substituted arylglyoxals, alkylamines, cyclohexyl isocyanide and 3-azido-(S)-2-(tert-butoxycarbonylamino)propanoic acid, followed by a Staudinger/aza-Wittig cyclization in the presence of triphenylphosphine, gave rise to enantiomerically pure N-cyclohexyl 4-alkyl-2-aryl-5-oxo-(S)-6-(tert-butoxycarbonylamino)-4,5,6,7-tetrahydro-1H-1,4-diazepine-3-carboxamides, that can be useful for new drug design. By the same sequence, p-substituted benzaldehydes, 2-aminobenzophenone, cyclohexyl isocyanide and (S)-3-phenyl-2-azidopropionic acid gave rise to N-cyclohexyl 2-((S)-3-benzyl-2-oxo-5-phenyl-2,3-dihydro-1H-benzo[e][1,4]diazepin-1-yl)-(R/S)-2-arylacetamides. 相似文献
14.
Gundurao Kolavi 《Tetrahedron letters》2006,47(16):2811-2814
Novel heterocyclic systems 2-alkyl/aryl-9-(2-hydroxybenzylidene)-7,9-dihydro-8H-[1,3,4]thiadiazolo[2′,3′:2,3]imidazo[4,5-d][1,2]diazepin-8-one and 9-(2-hydroxy-benzylidene)-3,3-dimethyl-3,4,7,9-tetrahydro-2H-11-thia-4b,6,7,10-tetraazaindeno[1,2-a]azulene-1,8-dione are synthesized via an intramolecular amidation reaction. An interesting ring opening and cyclization of 2-alkyl/aryl-6-(2-oxo-2H-chromen-3-yl)imidazo[2,1-b][1,3,4]thiadiazole-5-carbaldehyde and 6,6-dimethyl-8-oxo-2-(2-oxo-2H-chromen-3-yl)-5,6,7,8-tetrahydroimidazo[2,1-b][1,3]benzothiazole-3-carbaldehyde are discussed. 相似文献
15.
Balendu Singh 《Tetrahedron letters》2009,50(3):366-369
An efficient one-pot, three-component synthesis of novel 2-substituted-5-aryl-1-oxo-3-thioxo-1,2,3,5,11,11a-hexahydro-6H-imidazo-[1,5-b]-β-carbolines employing 1-aryl-1,2,3,4-tetrahydro-β-carboline-3-carboxylates, primary amines (or amino acid esters) and methyl 1-imidazolecarbodithioate as the thiocarbonyl transfer reagent is reported. 相似文献
16.
A one-pot stereoselective alkenylation of 1-(3-chlorophenyl)-3-methyl-1,4-dihydro-5-pyrazolone 2 by 2H-pyran-2-ones 1 to give (E,E)-5-aryl-5-[1-(3-chlorophenyl)-3-methyl-5-oxo-1,5-dihydropyrazol-4- ylidene]-3-methylsulfanyl-pent-3-en-carbonitrile/methyl carboxylate 3 has been delineated through ring transformation in moderate yields. 相似文献
17.
Azafulvenium methides generated by the thermal extrusion of SO2 from 1-methyl- and 1,1-dimethyl-1H,3H-pyrrolo[1,2-c]thiazole-2,2-dioxides undergo [1,8]H sigmatropic shifts to give vinylpyrroles. Flash vacuum pyrolysis of the C-vinylpyrroles affords 5-oxo-5H-pyrrolizines or C-allyl-1H-pyrroles. 相似文献
18.
Ashot Martirosyan Rafael Tamazyan Marina Alexanyan Vahan Martirosyan 《Tetrahedron letters》2010,51(2):231-233
The method for the synthesis of 6-imino-5-tetrahydro-1H-2-pyrrolylidenhexahydro-2,4-pyrimidinediones is described. It is shown that the reaction of phosphorus trichloride, 2-pyrrolidones and 6-aminopyrimidines brings to condensation producing 6-imino-5-tetrahydro-1H-2-pyrrolylidenhexahydro-2,4-pyrimidinediones as intermediates for the synthesis of C-azanucleosides. The reaction of 6-imino-1,3-dimethyl-5-tetrahydro-2-pyrrolylidenhexahydro-2,4-pyrimidinedione with benzoyl chloride produces 10-benzoyl-2,4-dimethyl-6-phenyl-1,2,3,4,8,9-hexahydropyrimido[5,4-e]pyrrolo[1,2-c]pyrimidine-1,3-dione. A method for the selective reduction of the carbomethoxy group of methyl 5-(4-imino-1,3-dimethyl-2,6-dioxohexahydro-5-pyrimidinyliden)-2-pyrrolidine carboxylate by system NaBH4/1,4dioxane/CoCl2/PEG-400 is described. 相似文献
19.
An efficient and stereocontrolled synthesis of phenylalanine- and tryptophan-derived 5-phenyl-1,4-benzodiazepines is described. This new methodology involves, as a key step, the synthesis of 5-phenyl-2,3-dihydro-1H-1,4-benzodiazepines by a one-pot cyano reduction and reductive cyclization of the appropriate amino nitrile, which were obtained via a modified Strecker reaction of N-protected alpha-amino aldehydes with 2-aminobenzophenone and trimethylsilyl cyanide. The subsequent reduction of these 2,3-dihydro-1H-1,4-benzodiazepines, followed by regioselective alkylation or acylation at position 4, led to 2,4-disubstituted-5-phenyl-2,3,4,5-tetrahydro-1H-1,4-benzodiazepine. 相似文献
20.
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