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1.
The reaction of 7-acetoxyquinoline with trifluorosulfonate esters of primary alcohols in methylene chloride or acetonitrile, followed by acid hydrolysis, provides a general synthesis of 1-substituted-7-hydroxyquinolines, whose phenolate anions are fluorescent. 相似文献
2.
Yang-i Lin S. R. Petty F. M. Lovell N. A. Perkinson S. A. Lang 《Journal of heterocyclic chemistry》1980,17(5):1077-1080
The synthesis of 4-substituted-4H-1,2,4-triazole-3-thiols and 3-methylthio-4-substituted-4H-1,2,4-triazoles by the condensation of 4-substituted-3-thiosemicarbazides with dimethylformamide dimethyl acetal or dimethylacetamide dimethyl acetal is described. A discussion of the mechanistic pathway is included. 相似文献
3.
Philip E. Morris Arthur J. Elliott John A. Montgomery 《Journal of heterocyclic chemistry》1999,36(2):423-427
In a recent publication, we have the described the synthesis of 7-substituted-2-amino-1,5-dihydro-4H-pyrrolo[3,2-d]pyrimidin-4-ones which are potent inhibitors of the enzyme Purine Nucleoside Phosphorylase from the corresponding 3-aminopyrroIe-2-carboxylate esters. A key step in the synthesis is condensation of the amino group with the highly reactive guanylating reagents 3 or 4 followed by annulation. The furo[3,2-d]pyrimidin-4-one and thieno[3,2-d]pyridin-4-one are closely related rings systems. However, these rings have not been reported in the literature with a 2-amino, substituent which would arise from such guanylation reactions. In this report, the syntheses of the novel furans 5 are described based on our improved pyrrole synthesis (Scheme 1). The syntheses of the novel thiophenes 6 are described. The guanylation of 5 and 6 were studied and compared to 2. The 3-amino group of 5 and 6 failed to react with 3 or 4 under mild acid catalysis; conditions under which 2 easily condensed. Guanylation was finally achieved by generating the carbodiimide intermediate of 3 under mercury catalysis affording the guanylated adducts which were converted to the novel 2-aminothieno- and furo[3,2-d]pyrimidin-4-ones 16. 相似文献
4.
Javier Parcerisa 《Tetrahedron》2008,64(3):500-507
An easy route to the synthesis of 2-substituted-7-azaindole derivatives has been developed. The carbinol intermediate dissolved in DMF undergoes cyclization upon treatment with sodium hydride, trifluoroacetic anhydride, and trifluoroacetic acid at 120 °C in a straightforward and one-pot step. An alternative methodology using (CF3SO2)2O in acetonitrile in basic media followed by the addition of CF3COOH affords the expected 2-substituted azaindole in best yields. 相似文献
5.
Tommy J. Mccord Michael R. Warner Paul L. Shafer Rose M. Davis Disher Alvie L. Davis 《Journal of heterocyclic chemistry》1985,22(1):141-144
A new method was developed for the synthesis of some 7-substituted 3-chloro-3,4-dihydro-l-hydroxycarbostyrils 3c-g in which α-chloro-β-(4-substituted-2-nitrophenyl)propionic acids 2c-g were reductively cyclized by catalytic hydrogenation over platinum-on-carbon sulfided catalyst. In particular, this method was applied to α-chloro-β-(2-nitrophenyl)propionic acids bearing 4-methyl 2c , 4-ethyl 2d , 4-ethoxy 2e , 4-(n-butyl 2f and 4-phenyl 2g substituents to afford good yields of the corresponding 7-methyl 3c , 7-ethyl 3d , 7-ethoxy 3e , 7-(n-butyl) 3f , and 7-phenyl 3g substituted 3-chloro-3,4-dihydro-l-hydroxycarbostyrils. The various 4-substituted α-chloro-β-(2-nitrophenyl)propionic acids 2c-q were synthesized by reacting the in situ diazotized salts of the appropriate 4-substituted-2-nitroanilines in aqueous acetone with acrylic acid in the presence of cuprous chloride and hydrochloric acid. All compounds prepared in this study were characterized by microanalytical and ir and nmr spectral data. 相似文献
6.
F. Guerrera L. Salerno M. C. Sarv M. A. Siracusa 《Journal of heterocyclic chemistry》1995,32(2):591-594
The synthesis of novel 1-alkyl or 1-aryl-2-(4-substituted-1-piperazinyl)-1-H-benzothieno[2,3-d]imidazoles 7e-x starting from 2-nitro-3-bromobenzo[b]thiophene is described. These compounds were prepared as potential H1-antihistaminic agents. 相似文献
7.
Raymonde Nasielski-Hinkens Marie Benedek-Vamos Daniel Maetens 《Journal of heterocyclic chemistry》1980,17(5):873-876
The synthesis of 9-substituted-1,4,5,8-tetraazaphenanthrenes was undertaken in the course of a study aimed at the preparation of organometallic complexing agents. 相似文献
8.
The synthesis of some 7-substituted-3-azabicyclo[3.3.1]nonanes is described. Routes followed were the debenzoylation of the 7-benzoyl derivative 7 and the decarboxylation of the 7-carboxy compounds 21 and 27. The so-obtained 7-oxo-N-tosyl-3-azabicyclo[3.3.1]nonanes 8and 11 show an extremely low reactivity towards a series of nucleophilic reagents. From analysis of the 1H NMR spectral data of a series of derivatives, the twin-chain conformation for the 7-exo compounds and the chair-boat conformation for the 7-endo compounds is indicated. 相似文献
9.
Jun Segawa Masahiko Kitano Kenji Kazuno Masami Tsuda Ichiro Shirahase Masakuni Ozaki Masato Matsuda Masahiro Kise 《Journal of heterocyclic chemistry》1992,29(5):1117-1123
A series of 8-substituted-7-fluoro-5-oxo-5H-thiazolo[3,2-a]quinoline-4-carboxylic acids was prepared and evaluated for antibacterial activity. These compounds were synthesized from ethyl 2-mercaptoquinoline-3-carboxylates 17 which were obtained from anilines 11 by a route involving an intramolecular cyclization reaction. 相似文献
10.
11.
Trisubstituted 1,4,5,6,-tetrahydro-7H-indolones are obtained in a one-pot synthesis from conjugated nitroolefins and α-ketoenamines derived from α-amino esters and cyclohexane-1,2-dione. In some cases bicyclo[3.2.1]octan-8-one and 1,2-oxazine N-oxide derivatives are isolated. 相似文献
12.
Vijay V. Dabholkar Faisal Y. Ansari 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):298-305
Ultrasound accelerated synthesis of 2,3-(substituted)benzo-1,4-thiazino[5,6-b]-4H-9H-7- methyl-10-oxoquinolines (4), 7-substituted-2,2-dimethyl-2,3-dihydro-1H,10H-phenothiazin- 4-one (5), 4-substituted-3,9, 10-trihydro-11-oxo-quinolino[2,3-b]-1,3,4-thiadiazino[2,3-d]- 1,2,4-triazole (6), and 7,7-dimethyl-7,8-dihydro-3H,5H,6H-1,2,4-triazolo[3,4-b][1,3,4] benzothiadiazin-9-one (7) from carbostyril and dimedone using sulfur powder and iodine as a catalyst in THF is reported. The structures of the compounds have been elucidated on the basis of spectral and elemental analysis. 相似文献
13.
Carlos Peinador Vicente Ojea Jos Ma. Quintela 《Journal of heterocyclic chemistry》1992,29(7):1693-1702
Ready, convenient synthesis for 8-cyano-7-ethoxy-4-oxo-9-phenyl-2-substituted-1,2,3,-4-tetrahydropyrido-[3′,2′:,4,5]thieno[3,2-d]pyrimidines 5 , 8-cyano-7-ethoxy-4-oxo-9-phenyl-2-substituted-3,4-dihydropyrido[3′,2-: 4,5]thieno[3,2-d]pyrimidines 6 , 4-chloro-8-cyano-7-ethoxy-9-phenyl-2-substitutedpyrido[3′,2′:4,5]thieno[3,2-4 -pyrimidines 7 and 8-cyano-7-ethoxy-2-(2′-nitrophenyl)-9-phenyl-4-substitutedpyrido[3′,2′:4,5]thieno[3,2- d ]pyrimidines 8-18 from 2-chloro-3,5-dicyano-6-ethoxy-4-phenylpyridine 1 via 3,5-dicyano-6-ethoxy-2-mercapto-4-phenylpyridine 2 and aminocarboxamide 4 are reported. In addition, the reaction of hydrazino derivative 12 with reagents such as formic acid and triethyl orthoformate yielded the fused tetraheterocyclic 8-cyano-9- ethoxy-5-(2′-nitrophenyl)- 7-phenylpyrido[3′,2′:4,5]thieno[2,3-e]-1, 2,4-triazolo[4,3-c]pyrimidine system 19 . 相似文献
14.
M. Q. Zhang A. Haemers D. Vanden Berghe S. R. Pattyn W. Bollaert I. Levshin 《Journal of heterocyclic chemistry》1991,28(3):673-683
A series of 7-(2-substituted-4-thiazolyl and thiazolidinyl)-1-ethyl-1,4-dihydro-4-oxoquinoline-3-carboxylic acids and their 6-fluoro analogues were synthesized. The Hantzsch method was used for the preparation of the thiazolylquinolones. The thiazolidinylquinolones were synthesized by quaternization of the corresponding thiazolyl analogues, followed by reduction of the obtained thiazolium salts with sodium borohydride in aqueous solution. Antibacterial activity was tested in vitro. Most of the compounds were inactive against Gram-negative bacteria but some of them showed however good activity against Gram-positive bacteria and mycobacteria. This activity pattern is rarely found among the quinolone antibacterials. 相似文献
15.
Two improved methods have been developed for the synthesis of 5-substiluted-4-amino-3-mercapto-(4H)-1,2,4-triazoles. One of these involves the direct hydrazinolysis of potassium 3-aroyldithiocarbazates and the other involves ring-opening and reclosure of 5-substituted-2-mereapto-1,3,4-oxadiazoles to the aminomercaptotriazoles. Both of these methods offer advantages over the classic Hoggarth synthesis. 相似文献
16.
(E)-1-substituted-1,3-dienes are obtained with high stereoselectivity by the thermal extrusion of SO2 from 2-substituted-2,5-dihydrothiophene-1,1-dioxides generated by a retro Diels-Alder reaction. An application to the synthesis of (E)-9,11-dodecadien- 1-yl acetate, a sex pheromone of the red-bollworm moth is described. 相似文献
17.
Coumarins modified with dipeptides were prepared by condensation of N-hydroxysuccinimide esters of 2-(3,4,8-substituted-2-oxo-2H-7-chromenyloxy)-and 2-(3,4-substituted-7-methyl-2-oxo-2H-5-chromenyloxy)acetic and-propionic acids with amino acids and dipeptides.
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Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 239–242, May–June, 2008. 相似文献
18.
Original 2-methyl-7-nitro-5-substituted-2,3-dihydroimidazo[5,1-b]oxazoles were prepared by reacting 1-(2,5-dibromo-4-nitro-1H-imidazol-1-yl)propan-2-ol and various arylboronic acids through “one-pot” cyclization and Suzuki–Miyaura reactions under microwave irradiation. 相似文献
19.
Mercedes T. Grande Gregorio G. Trigo Mnica M. Sllhuber 《Journal of heterocyclic chemistry》1986,23(3):929-933
Some 2- and 3-substituted-1,2,3,4-tetrahydrodibenzo[f,h]isoquinolines were prepared by a synthetic scheme involving a selective Borch reduction of an amide to the corresponding amine and a Friedel-Crafts cyclization to obtain the dibenzo[f,h]isoquinoline system. The title compounds, which have a similarity to the cell growth inhibitory alkaloid cryptopleurine, failed to exhibit significant protein synthesis inhibitory activity. 相似文献
20.
Michael G. Kallitsakis Dimitra J. Hadjipavlou-Litina Aikaterini Peperidou Konstantinos E. Litinas 《Tetrahedron letters》2014
The synthesis of 4-hydroxy-3-[(E)-2-(6-substituted-9H-purin-9-yl)vinyl] coumarins has been achieved from the reactions of 4-hydroxycoumarin with 2-(6-substituted-9H-purin-9-yl)acetaldehydes in DMF under heating. The new compounds showed significant lipoxygenase inhibitory activity (e.g., 6a: IC50 = 6.25 μM). 相似文献