- Synthesis of new quinolinones from 3-nitropyranoquinolinones
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Alkaline hydrolysis of 3-nitropyranoquinolinones (6-alkyl-4-hydroxy-3-nitro-2H-pyrano[3,2-c]quinoline-2,5(6H)-diones) for different reaction times gave five products which were formed by the progressive degradation of the nitropyrano ring. Varying amounts of 3-nitroacetylquinolinones, quinolinones with side-chains of β- And β-ketoacids, quinolinone-3-carboxylic acids and 4-hydroxyquinolinones were isolated. With the aim of preparing new biologically active quinolone derivatives, the products of reaction of the 3-nitropyranoquinolinones with side-chains of α- And β-ketoacids with some nitrogen and carbon nucleophiles were also studied, some giving rise to annulated products.
- Morsy, Jehan M.,Hassanin, Hany M.,Ismail, Mostafa M.,Abd-Alrazk, Marwa M.A.
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- Enzymatic formation of quinolone alkaloids by a plant type III polyketide synthase
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(Chemical Equation Presented) Benzalacetone synthase from Rheum palmatum efficiently catalyzed condensation of N-methylanthraniloyl-CoA (or anthraniloyl-CoA) with malonyl-CoA (or methylmalonyl-CoA) to produce 4-hydroxy-2(1H)-quinolones, a novel alkaloidal scaffold produced by a type III polyketide synthase (PKS). Manipulation of the functionally divergent type III PKSs by a nonphysiological substrate thus provides an efficient method for production of pharmaceutically important quinolone alkaloids.
- Abe, Ikuro,Abe, Tsuyoshi,Wanibuchi, Kiyofumi,Noguchi, Hiroshi
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- Substituted quinolinones. Part 19. New and unexpected results from oxidation of 3-acetyl-1-alkyl- 4-hydroxyquinolin-2(1H)-ones using selenium dioxide
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Oxidation of 3-acetyl-1-alkyl-4-hydroxyquinolin-2(1H)-ones using selenium dioxide under Riley conditions was described. The oxidation reaction produced a mixture of 2 unexpected α-keto acid and its dehydrated dimer derivatives. The oxidation reaction was studied under different reaction conditions in order to maximize the yields and optimize reaction conditions. Also, 1-alkyl-4-hydroxy-3-(2-nitroacetyl)quinolin-2(1H)-one and/or 3-acetyl-1-alkyl-4-diflouro-boryloxyquinolin-2(1H)-one derivatives were subjected to the same oxidation reaction giving rise improved reaction yields and selectivity in case of the boron-complex. Alkaline degradation of the dehydrated dimers led to formation of the 4-hydroxy-2-oxoquinoline-3-carboxylic acids while under the same conditions the α-keto acids underwent deoxalylation.
- Abass, Mohamed,Allimony, Hassan A.,Hassan, Heba
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- Methylation of 4-Hydroxy-2-quinolone
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The reaction of 4-hydroxy-2-quinolone (1a) with methyl iodide/potassium hydroxide in boiling acetone gave a mixture of 1-methyl-4-methoxy-2-quinolone (1d), 1,3-dimethyl-4-methoxy-2-quinolone (1e), and 1,3,3-trimethyl-2,4-dioxo-1,2,3,4-tetrahydroquinoline (2).As by-product 2,4-dimethoxyquinoline (3) was identified.Under the same conditions 4-methoxy-2-quinolone (1c) yielded 1d, 1e, 2 and 3, while 1-methyl-4-hydroxy-2-quinolone (1b) gave 1d, 1e and 2.
- Reisch, Johannes,Mester, Iuliu
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- BACTERIOSTATIC HETEROCYCLES FROM EUODIA LUNU-ANKENDA
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A new constituent characterized as 8-acetyl-3,4-dihydroxy-5,7-dimethoxy-2,2-dimethylchroman has been isolated together with alloevodionol-7-methyl ether, 4-methoxy-1-methyl-2(1H) quinolinone, evolitrine, isoevodionol and its methyl ether from the aerial parts of Euodia lunu-ankenda.Its structure was confirmed by its transformation to alloevodionol-7-methyl ether. 4-Methoxy-1-methyl-2(1H)quinolinone and its isomer were synthesized by a modified procedure.Key Word Index - Euodia lunu-ankenda; Rutaceae; 8-acetyl-3,4-dihydroxy-5,7-dimethoxy-2,2-dimethylchroman; alloevodionol-7-methyl ether; 4-methoxy-1-methyl-2(1H)quinolinone; isoevodionol; isoevodionol methyl ether; antibacterial activity.
- Manandhar, Mangala D.,Hussaini, Falak A.,Kapil, Randhir S.,Shoeb, Aboo
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- Rapid preparation of pyranoquinolines using microwave dielectric heating in combination with fractional product distillation
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4-Hydroxy-6-methyl-2H-pyrano[3,2-c]quinoline-2,5(6H)-dione was prepared by microwave-assisted cyclocondensation of N-methylaniline with 2 equiv of diethyl malonate. Key to the success of the synthesis was the use of open vessel controlled microwave heating technology, allowing the simultaneous removal of the formed ethanol from the reaction mixture by fractional distillation.
- Razzaq, Tahseen,Kappe, C. Oliver
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- One-step Synthesis of 3-Unsubstituted 4-Hydroxy-2(1H)-Quinoline
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3-Unsubstituted 4-hydroxy-2(1H)-quinolone (DHQ) derivatives were synthesized from aniline derivatives and diethyl malonate at low temperature using AlCl3 as catalyst and Eaton reagent as acidic environment. A reaction mechanism was proposed and elucidated. Different synthetic intermediates are specially prepared or purified and used to understand the reaction and validation mechanism.
- Menglin, Ma,Qingrong, Sun,Weiqing, Yang,Xingyi, Wang,Yinan, Xu
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p. 435 - 441
(2021/11/22)
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- Asymmetric synthesis of tetrahydropyran[3,2-c]quinolinones via an organocatalyzed formal [3 + 3] annulation of quinolinones and MBH 2-naphthoates of nitroolefin
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An efficient asymmetric and enantio-swithchable organocatalytic [3 + 3] annulation reaction using MBH-2-naphthoates of nitroalkenes and 4-hydroxyquinolin-2(1H)-ones has been developed. Densely substituted tetrahydropyrano[3,2-c]quinolinones scaffolds with two adjacent stereogenic centers are obtained with high yield (up to 95% yield) and good stereoselectivities (up to >20:1 dr and 96% ee) in an enantio-switchable manner. Furthermore, gram scale synthesis was achieved and the nitro group could easily transform into an amino group without any appreciable loss in the diastereo- and enantioselectivity.
- Li, Jian,Hu, Qi-Long,Chen, Xue-Ping,Hou, Ke-Qiang,Chan, Albert S.C.,Xiong, Xiao-Feng
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p. 697 - 700
(2019/09/30)
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- Engineered Biosynthesis of Fungal 4-Quinolone Natural Products
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Quinolone-containing natural products are widely found in bacteria, fungi, and plants. The fungal quinolactacins, which are N-methyl-4-quinolones, display a wide spectrum of biological activities. Here we uncovered a concise nonribosomal peptide synthetase pathway involved in quinolactacin A biosynthesis from Penicillium by using heterologous reconstitution and in vitro enzymatic synthesis. The N-desmethyl analog of quinolactacin A was accessed through the construction of a hybrid bacterial and fungi pathway in the heterologous host.
- Liu, Mengting,Ohashi, Masao,Tang, Yi
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p. 6637 - 6641
(2020/09/02)
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- Novel Pyrazoloquinolin-2-ones: Design, synthesis, docking studies, and biological evaluation as antiproliferative EGFR-TK inhibitors
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Two new series of diethyl 2-[2-(substituted-2-oxo-1,2-dihydroquinolin-4-yl)hydrazono]-succinates 6a-g and 1-(2-oxo-1,2-dihydroquinolin-4-yl)-1H-pyrazoles 7a-f have been designed and synthesized. The structures of the synthesized compounds were proved by IR, mass, NMR (2D) spectra and elemental analyses. The target compounds were evaluated for their in vitro cytotoxic activity against 60 cancer cell lines according to NCI protocol. Consequently, seven compounds were further examined against the most sensitive cell lines, leukemia CCRF-CEM, and MOLT-4. 5-Amino-1-(6-bromo-2-oxo-1,2-dihydroquinolin-4-yl)-1H-pyrazole-3,4-dicarbonitrile (7f) was the most active product, with IC50 = 1.35 uM and 2.42 uM against MOLT-4 and CCRF-CEM, respectively. Also, it showed a remarkable inhibitory activity compared to erlotinib on the EGFR TK with IC50 = 247.14 nM and 208.42 nM, respectively. Cell cycle analysis of MOLT-4 cells treated with 7f showed cell cycle arrest at G2/M phase (supported by Caspases, BAX and Bcl-2 studies) with a significant pro-apoptotic activity as indicated by annexin V-FITC staining. Moreover, the docking study indicated that both the pyrazole moiety and the quinolin-2-one ring showed good fitting into EGFR (PDB code: 1M17). In order to interpret SAR of the designed compounds, and provide a basis for further optimization, molecular docking of the synthesized compounds to known EGFR inhibitors was performed. The study illustrated the effect of several factors on the compounds’ activity.
- Elbastawesy, Mohammed A.I.,Aly, Ashraf A.,Ramadan, Mohamed,Elshaier, Yaseen A.M.M.,Youssif, Bahaa G.M.,Brown, Alan B.,El-Din A Abuo-Rahma, Gamal
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- Stereoselective synthesis of natural product inspired carbohydrate fused pyrano[3,2-: C] quinolones as antiproliferative agents
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Pyrano[3,2-c]quinolone structural motifs are commonly found in natural products with diverse biological activities. As part of a research programme aimed at developing the efficient synthesis of natural product-like small molecules, we designed and developed the microwave assisted, facile stereoselective synthesis of two series of carbohydrate fused pyrano[3,2-c]quinolone derivatives (n = 23) starting from 2-C-formyl galactal and 2-C-formyl glucal, reacting with various 4-hydroxyquinolones in shorter reaction times (15-20 min). The antiproliferative activity of these synthesized pyrano[3,2-c]quinolones was determined against MCF-7 (breast) and HepG2 (liver) cancer cells. The selected library members displayed low micromolar (3.53-9.68 μM) and selective antiproliferative activity. These findings on carbohydrate fused pyrano[3,2-c]quinolone derivatives are expected to provide new leads for anticancer drug discovery.
- Kumari, Priti,Narayana, Chintam,Dubey, Shraddha,Gupta, Ashish,Sagar, Ram
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supporting information
p. 2049 - 2059
(2018/03/26)
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- Water-mediated, green, and efficient synthesis of bisquinolones under catalyst-free conditions
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Water-mediated, green, and efficient synthesis involving condensation of 4-hydroxy-1-methylquinoline-2(1H)-one (3) with different aromatic and heterocyclic aldehydes (4a–n) leading to 3,3′-(arylmethylene)-bis-(4-hydroxy-1-methylquinolin-2(1H)-one) 5(a–n) under catalyst-free conditions is described. This reaction has an easy workup without using column chromatography and provides excellent yields of the products in shorter reaction times. It does not require any catalyst and uses water as the medium which is the greenest solvent. 3 required in this work was itself obtained by condensation of N-methylaniline (1) with malonic acid (2) in the presence of POCl3using a previously reported procedure.
- Madhu, Bandi,Reddy, Ch. Venkata Ramana,Dubey, Pramod Kumar
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p. 421 - 427
(2017/02/24)
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- Natural product Hirtellanine B and its derivatives in the preparation process for the preparation of medicine for treating tumor with the application of the
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The present invention provides a preparation method of a natural product Hirtellanine B, wherein 2,4,6-trihydroxyacetophenone is adopted as a raw material, and steps of compound a preparation, compound b preparation, compound c preparation, compound d preparation, compound e preparation, compound f preparation, compound g preparation, and the like are performed to prepare the natural product Hirtellanine B. According to the present invention, biological activity screening is performed on Hirtellanine B and 14 Hirtellanine B derivatives, and results show that the natural product Hirtellanine B can inhibit proliferations of Jurkat cells, Raji cells and K562 cells, and the compounds provide a certain inhibition activity for tumor cells. The method has characteristics of easily available raw material, high reaction yield and reasonable operation, and is suitable for industrial production. The Hirtellanine B and the derivatives thereof can be used for preparing tumor treatment drugs, and have great clinical values. The natural product Hirtellanine B preparation method reaction formulas are as the follows.
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- Synthesis of Unnatural 2-Substituted Quinolones and 1,3-Diketones by a Member of Type III Polyketide Synthases from Huperzia serrata
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A curcuminoids, benzalacetone-, and quinolone-producing type III polyketide synthase (HsPKS3) from Huperzia serrata uniquely catalyzes the formation of unnatural 2-substituted quinolones and 1,3-diketones via head-to-head condensation of two completely different substrates. The broad range of substrate tolerance of HsPKS3 facilitates accessing structurally diverse 2-substituted quinolones and 1,3-diketones.
- Wang, Juan,Wang, Xiao-Hui,Liu, Xiao,Li, Jun,Shi, Xiao-Ping,Song, Yue-Lin,Zeng, Ke-Wu,Zhang, Le,Tu, Peng-Fei,Shi, She-Po
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supporting information
p. 3550 - 3553
(2016/08/16)
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- Cloning and structure-function analyses of quinolone- and acridone-producing novel type III polyketide synthases from citrus microcarpa
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Background:Type III polyketide synthases (PKSs) synthesize various polyketide and alkaloid scaffolds. Results:QNS synthesizes quinolone as the single product, whereas ACS produces acridone as the major product. Conclusion:QNS and ACS are novel quinolone- and acridone-producing type III PKSs, respectively. Significance:Structure-function analyses of QNS and ACS provide insights into molecular bases for alkaloid biosyntheses.
- Mori, Takahiro,Shimokawa, Yoshihiko,Matsui, Takashi,Kinjo, Keishi,Kato, Ryohei,Noguchi, Hiroshi,Sugio, Shigetoshi,Morita, Hiroyuki,Abe, Ikuro
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p. 28845 - 28858
(2013/10/22)
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- Efficient synthesis of bicyclo[3.3.1]nonane systems via tandem 1,3-dinucleophilic addition of 4-hydroxy-2-quinolinones to quinolinium salts
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The synthesis of bicyclo[3.3.1]nonane systems is reported. The synthesis is based on the tandem 1,3-dinucleophilic addition of 4-hydroxy-2-quinolinone to quinolinium salts.
- Moghaddam, Firouz Matloubi,Mirjafary, Zohreh,Saeidian, Hamdollah,Foroushani, Behzad Koushki,Nourian, Saghar
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scheme or table
p. 1941 - 1949
(2012/06/29)
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- Synthesis of 4-hydroxy-3-formylideneamino-lH/methyl/phenylquinolin-2-ones
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An efficient method for the synthesis of 4-hydroxy-3-formylideneamino-l H/methyl/phenylquinolin-2-ones by the condensation of corresponding 4-hydroxy-3-formyl-l///methyl/phenylquinolin-2-one with substituted anilines/aliphatic primary amines is reported. The carboxaldehyde in turn is prepared starting either from substituted anilines or benzoic acid. The structures of compounds are established by the elemental analysis and spectral data.
- Bhudevi,Ramana,Mudiraj, Anwita,Reddy
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experimental part
p. 255 - 260
(2009/12/03)
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- A convenient one-pot synthesis of pyrano[3,2-c]quinolin-2,5(6H)-dione and 2H,5H-pyrano[3,2-c]chromene-2,5-dione derivatives
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The preparation of novel pyrano[3,2-c]quinolin-2,5(6H)-dione and 2H,5H-pyrano[3,2-c]chromene-2,5-dione derivatives starting from 4-hydroxyquinolin-2(1H)-ones and 4-hydroxy-2H-chromene-2-one with chlorocarbonyl ketenes is described. This method provides a new route to produce fused pyrano derivatives in good to excellent yields in a short experimental time. Georg Thieme Verlag Stuttgart.
- Sheibani, Hassan,Mosslemin, Mohammad Hossein,Behzadi, Soheila,Islami, Mohammad Reza,Saidi, Kazem
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p. 435 - 438
(2007/10/03)
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- Synthesis of coumarins, 4-hydroxycoumarins, and 4-hydroxyquinolinones by tellurium-triggered cyclizations
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Coumarins, 4-hydroxycoumarins, and 4-hydroxyquinolin-2(1H)-ones can be conveniently prepared by treatment of α-halocarboxylic acid esters of salicylaldehyde, o-hydroxyacetophenone, methyl salicylate, and methyl N-methyl- or N-phenylanthranilates with sodium or lithium telluride. Phenylketene formation competes with cyclization of the α-chlorophenylacetate ester of methyl salicylate as demonstrated by a trapping experiment with benzylamine. Elemental tellurium may be recovered and reused.
- Dittmer, Donald C.,Li, Qun,Avilov, Dimitry V.
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p. 4682 - 4686
(2007/10/03)
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- A new synthesis of 4-alkyl/aryl-5,6-dihydro-2H-pyrano[3,2-c]quinoline-2,5-diones and molecular rearrangement of their 3-bromo derivatives to 2-alkyl/aryl-4-oxo-4,5-dihydrofuro[3,2-c]quinoline-3-carboxylic acids
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The treatment of 3-acyl-4-hydroxy-1H-quinolin-2-ones (1) with ethyl (triphenylphosphoranylidene)acetate leads to 5,6-dihydro-2H-pyrano[3,2-c]quinoline-2,5-diones (2), which were brominated to 3-bromo derivatives (4). Alkaline hydrolysis of 4 gives 2-alkyl/aryl-4-oxo-4,5-dihydrofuro[3,2-c]quinoline-3-carboxylic acids (6), which were decarboxylated to 2-alkyl/aryl-5H-furo[3,2-c]quinolin-4-ones (8). The reaction of 3-acetyl-4-hydroxy-1-methyl-1H-quinolin-2-one (1a) with ethyl (triphenylphosphoranylidene)chloroacetate proceeds not only at the acetyl but also at the amide group to give a mixture of ethyl 3,5-dimethyl-4-oxo-4,5-dihydrofuro[3,2-c]quinoline-2-carboxylate (11a) and ethyl 4,6-dimethyl-2-oxo-5,6-dihydro-2H-pyrano[3,2-c]quinolin-5-ylidene- (chloro)acetate (12a). The reaction mechanism of the molecular rearrangement of 4 to 6 is discussed.
- Klasek, Antonin,Koristek, Kamil,Sedmera, Petr,Halada, Petr
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p. 799 - 815
(2007/10/03)
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- Rhodium-Mediated Dipolar Cycloaddition of Diazoquinolinediones
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As an entry to furoquinoline structures of natural origin, the rhodium-mediated dipolar cycloaddition of diazoquinolinediones with alkenes and alkynes has been examined. Because of the unsymmetrical nature of the diazo compounds, both linear and angular furoquinoline products are possible. For the most part, a mixture of regioisomers is generated in moderate to good yields, though in a few cases dominant products are obtained in high yields. The products can be further converted to naturally occurring alkaloids such as isodictamnine. A novel observation in this work is that catalytic quantities of acid enhance the yield and regiochemical control in the cycloaddition.
- Pirrung, Michael C.,Blume, Florian
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p. 3642 - 3649
(2007/10/03)
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- 4-hydroxy-2-quinolones. 31. 3-amino-1R-2-oxo-4-hydroxyquinolines and their acyl derivatives
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An alternative method has been developed for preparing and studying the antioxidant activity of 3-acylamino-2-oxo-4-hydroxyquinolones. Results are presented from an investigation of the antithyroid and antimicrobial action of the intermediate 2-oxo-3-(1-pyridinio)quinolin-4-olates and the 3-amino-2-oxo-4-hydroxyquinolines. 1997 Plenum Publishing Corporation.
- Ukrainets,Taran,Sidorenko,Gorokhova,Ogirenko,Turov,Filimonova
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p. 960 - 970
(2007/10/03)
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- Ethyl Esters of Malonanilic Acids. Synthesis and Pyrolysis
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The pyrolysis under 170-220 deg C or boiling in DMF of malonanilic acids ethyl esters (2) is accompanied by formation of malonic acids symmetric dianilides (7) with high yields.A possible mechanism for this transformation has been suggested.
- Ukrainets, Igor V.,Bezugly, Peter A.,Treskach, Vladimir I.,Taran, Svetlana G.,Gorokhova, Olga V.
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p. 10331 - 10338
(2007/10/02)
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- Pyranopyran-2,5-diones, 1. - Convenient Synthesis of Pyranopyrano-quinolinetriones
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Reaction of malondiamides 1 with malonyl chloride (5) leads to 2,5-dioxo-2H,5H-pyranopyrans 7, which readily react with diazomethane to give the corresponding methyl ethers 8.Thermically induced cyclisation of 8 affords 7,12-dihydro-2H,5H-pyranopyranoquinoline-2,5,12-triones 9.Acidic hydrolysis of 9 yields 4H-pyranoquinoline-4,5(10H)-diones 10, while basic hydrolysis of 9 gives 4-hydroxy-2(1H)-quinolinones 11. Key Words: 2H,5H-Pyranopyrans, 2,5-dioxo- / 2H,5H-Pyranopyranoquinoline-2,5,12-triones, 7,12-dihydro- / 4H-Pyranoquinoline-4,5-diones, 5,10-dihydro-
- Saalfrank, Rolf W.,Hoerner, Bernd
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p. 841 - 844
(2007/10/02)
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- Heck reactions of 3-iodo-N-methyl-quinolin-2(1H)-ones with 2-methylbut-3-en-2-ol
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Treatment of 4-acetoxy-3-iod-N-methyl-quinolin-2(1H)-one, 3-iod-N-methyl-4-tosyloxy-quinolin-2(1H)-one and 3-iod-4-methoxy-N-methyl-quinolin-2(1H)-one with 2-methylbut-3-en-2-ol under Heck conditions led to the related (E)-3-(3-methylbut-1-en-3-olyl)-derivatives, potential precursors of dimeric quinolines. Dehydration of the tertiary hydroxy group of 4-methoxy-(E)-3-(3-methylbut-1-en-3-olyl)-N-methyl-quinolin-2(1H)-one with acetic acid gave 4-methoxy-(E)-3-(3-methylbut-1,3-dienyl)-N-methyl-quinolin-2(1H)-one.
- Reisch,Iding
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p. 579 - 582
(2007/10/02)
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- Organic Azides in Heterocyclic Synthesis, 11. Ring Closure of 3-Acetyl-4-azido-2-quinolones to Isoxazoloquinolones
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Thermolysis of the 3-acetyl-4-azido-2-quinolone 6, which was obtained from the corresponding 4-tosyloxy derivative 5, afforded the ring closed isoxazoloquinolone 7 in good yield.
- Roschger, Peter,Stadlbauer, Wolfgang
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p. 821 - 823
(2007/10/02)
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- MUSHROOM TYROSINASE CATALYSED SYNTHESIS OF COUMENTANS, BENZOFURAN DERIVATIVES AND RELATED HETEROCYCLIC COMPOUNDS
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Full details of an improved synthesis of coumestan derivatives and their structural analogues, viz., wedelolactone, 11-hydroxy aureol, 11-hydroxy coumestrol along benzofuran derivatives and related heterocyclic systems are reported by coupling of in situ generated o-quinones from catechols catalysed by mushroom tyrosinase with various reatants.
- Pandey, G.,Muralikrishna, C.,Bhalerao, U. T.
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p. 6867 - 6874
(2007/10/02)
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- Ylides of Heterocycles, VIII. Reactions of Iodonium-Ylides with Acids
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The reaction of various organic and inorganic acids (HX) with iodonium ylides 2 leads to nucleophilic substitution of the iodobenzene substituent by the anion X(-) to yield the heterocycles 5.Some of them are hydrolyzed to the hydroxy compounds 3 or reduced to the starting compounds 1 under the reaction conditions.Reaction of the iodonium ylide 2b with monomethyl sulfate gives the salt 9, which with bases undergoes nucleophilic substitution to compounds 8 and 10-12, respectively, or is converted to 2b again. - Keywords: 3-Acetoxy-4-hydroxy-2-quinolones; 2-Oxoquinoline-4-olates; 3-Substituted 4-hydroxy-2-quinolones
- Pongratz, Erik,Kappe, Thomas
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p. 231 - 242
(2007/10/02)
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- The Chemistry of 2H-3,1-Benzoxazine-2,4-(1H)-dione (Isatoic Anhydride). 10. Reactions With Ester Enolates. Synthesis of 4-Hydroxy-1-methyl-3-prenyL-2(1H)-quinolinones, Crucial Intermediates in the Synthesis of Quinoline Alkaloids
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N-Methylisatoic anhydride reacts with the lithium enolates of ester to produce β-ketoesters 4 in nearly quantitative yield.Thermal cyclization of these relatively unstable intermediates afford the corresponding 3-substituted-4-hydroxy-1-methyl-2(1H)quinolinones (5) in good yields.The reaction of the lithium enolate of 5-methyl-4-hexenoic acid ethylester (14) with various nuclear substituted isatoic anhydrides gives 4-hydroxy-1-methyl-3-prenyl-2(1H)-quinolinones 8,9 and 18 which are highly desirable intermediates in the synthesis of a variety of quinoline alkaloids.Treatment of 18 with DDQ furnishes oricine in 73percent yield.
- Coppola, Gary M.
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p. 1217 - 1221
(2007/10/02)
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- Anti-allergenic carbostyril derivatives
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A class of 4-hydroxy-3-nitroearbostyril derivatives are useful in the inhibition of certain types of antigen antibody reactions.
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