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1.
The development of a preparative route to a series of novel 4-(1H-indol-6-yl)-1H-indazole compounds as potential PDK1 inhibitors is described. The synthetic strategy centres on the late-stage Suzuki cross-coupling of N-unprotected indazole and indole fragments. The use of a monoligated palladium catalyst system was found to be highly beneficial in the cross-coupling reaction. The indazole and indole fragments were constructed by diazotisation/cyclisation and SNAr/reductive cyclisation sequences, respectively. 相似文献
2.
Synthetic strategies to gain access to all four isomers of 3-(3-chloro-1H-pyrazol-5-yl)quinoxalin-2(1H)ones with monosubstituted benzo core (i.e., compounds 8a–d) are described. Preparation of these heterocyclic compounds succeeded starting from only two different substituted 2-nitroanilines (i.e., 3-methoxy- and 4-methoxy-2-nitroaniline) in three or five steps, respectively. 相似文献
3.
Zhiyong Wang 《Tetrahedron》2008,64(8):1736-1742
An efficient and novel route for the synthesis of 1H-indol-2-yl-(4-aryl)-quinolin-2(1H)-one 1 via palladium-catalyzed site-selective cross-coupling reaction and cyclization process was described. Reaction of 3-bromo-4-trifloxy-quinolin-2(1H)-one 3 with arylboronic acid catalyzed by PdCl2(PPh3)2 afforded 3-bromo-4-aryl-quinolin-2(1H)-one 4, which then reacted with 2-ethynylaniline 5 via Pd-catalyzed Sonogashira coupling and CuI-mediated cyclization leading to the desired 1H-indol-2-yl-(4-aryl)-quinolin-2(1H)-one 1 in good yields. 相似文献
4.
Zwitterionic 4-hydroxy-2(1H)-quinolinone derivatives were synthesized through a unique reaction of 4-hydroxy-2(1H)-quinolinone with p-benzoquinone and N-heterocyclic aromatics. The zwitterions possessed astropisomeric nature. A possible mechanism of the reaction was presented. 相似文献
5.
A series of 2,3-dihydroquinazolin-4(1H)-ones and quinazolin-4(3H)-ones have been synthesized in good to excellent yields and high selectivity by one-pot reaction using isatoic anhydride, ammonium acetate (or amines), and aldehydes in ethanol or in DMSO under mild conditions, respectively. The reaction was efficiently promoted by 1 mol % Ga(OTf)3 and the catalyst could be recovered easily after the reactions and reused without evident loss of reactivity. 相似文献
6.
Shin-ichi NayaMakoto Nitta 《Tetrahedron》2003,59(21):3709-3718
Novel condensation reaction of tropone with N-substituted and N,N′-disubstitued barbituric acids in Ac2O afforded 5-(cyclohepta-2′,4′,6′-trienylidene)pyrimidine-2(1H),4(3H),6(5H)-trione derivatives (8a-f) in moderate to good yields. The 13C NMR spectral study of 8a-f revealed that the contribution of zwitterionic resonance structures is less important as compared with that of 8,8-dicyanoheptafulvene. The rotational barriers (ΔG‡) around the exocyclic double bond of mono-substituted derivatives 8a-c were obtained to be 14.51-15.03 kcal mol−1 by the variable temperature 1H NMR measurements. The electrochemical properties of 8a-f were also studied by CV measurement. Upon treatment with DDQ, 8a-c underwent oxidative cyclization to give two products, 7 and 9-substituted cyclohepta[b]pyrimido[5,4-d]furan-8(7H),10(9H)-dionylium tetrafluoroborates (11a-c·BF4− and 12a-c·BF4−) in various ratios, while that of disubstituted derivatives 8d-f afforded 7,9-disubstituted cyclohepta[b]pyrimido[5,4-d]furan-8(7H),10(9H)-dionylium tetrafluoroborate (11d-f·BF4−) in good yields. Similarly, preparation of known 5-(1′-oxocycloheptatrien-2′-yl)-pyrimidine-2(1H),4(3H),6(5H)-trione derivatives (14a-d) and novel derivatives 14e,f was carried out. Treatment of 14a-c with aq. HBF4/Ac2O afforded two kinds of novel products 11a-c·BF4− and 12a,c·BF4− in various ratios, respectively, while that of 14d-f afforded 11d-f. The product ratios of 11a-c·BF4− and 12a-c·BF4− observed in two kinds of cyclization reactions were rationalized on the basis of MO calculations of model compounds 20a and 21a. The spectroscopic and electrochemical properties of 11a-f·BF4− and 12a-c·BF4− were studied, and structural characterization of 11c·BF4− based on the X-ray crystal analysis and MO calculation was also performed. 相似文献
7.
Majid M. Heravi Bita Baghernejad Hossein A. Oskooie Rahim. Hekmatshoar 《Tetrahedron letters》2008,49(42):6101-6103
A simple and efficient synthesis of 2-(cyclohexylamino)-6,7-dihydro-3-aryl-1H-indole-4(5H)-ones was achieved via a one-pot multi-component reaction of cyclohexyl isocyanide, an aldehyde, a 1,3-dicarbonyl compound, and ammonium acetate in the presence of a catalytic amount of KHSO4 in acetonitrile. 相似文献
8.
The disclosure herein describes the rapid synthesis of 4-hydroxy-3-phenylquinolin-2(1H)-ones and variants via a solvent-free microwave cyclocondensation reaction using di-(2,4,6-trichlorophenyl)-2-phenylmalonate, which improves the general scope of this reaction. 相似文献
9.
Nina A. Larina Jerome Berthet Gaston Vermeersch Vladimir Khodorkovsky 《Tetrahedron》2010,66(42):8291-8299
Synthesis and characterization of a series of new 2-unsubstituted 3-(2-benzylbenzoyl)quinolin-4(1H)-ones is described. In addition to their potential biological activity, these compounds exhibit photoreversible photochromic properties in anaerobic conditions. Using the 1 and 2D NMR techniques we demonstrated that the coloration occurred owing to the formation of fluorescent 5a,6-dihydrobenzo[b]acridin-(5H)-ones. The photoreaction is stereoselective and the S,R-isomers are the major products (83%) whereas the S,S-isomers are the minor (6%). In addition, the irreversible formation of two oxidation products, 3-(2-benzoylbenzoyl)quinolin-4(1H)-ones, and acridin-12(5H)-one derivatives was observed in the presence of air. 相似文献
10.
Pd(PPh3)4 catalyzed Suzuki-Miyaura cross-coupling reactions of 4-tosyloxycoumarins or 4-tosyloxyquinolin-2(1H)-one with various potassium aryl trifluoroborates afforded the corresponding 4-substituted coumarins or 4-substituted quinolin-2(1H)-ones in good to excellent yield. 相似文献
11.
H.G Bonacorso I.S Lopes A.D Wastowski N Zanatta M.A.P Martins 《Journal of fluorine chemistry》2003,120(1):29-32
The synthesis of a novel series of eleven 6-aryl(5-methyl)-4-trifluoromethyl-2(1H)-pyrimidinones, where aryl=Ph, 4-CH3Ph, 4-FPh, 4-ClPh, 4-BrPh, 4-OCH3Ph and alkyl=H, CH3, from the reaction of 4-aryl-4-methoxy-1,1,1-trifluoro-3-buten-2-ones with urea in the presence of hydrochloric acid, is reported. Trifluoroacetylation of acetophenone- and propiophenone-dimethylacetals derived from phenones, was employed to obtain the precursors. 相似文献
12.
Ir catalysed alkylation of 4-hydroxy coumarin, 4-hydroxy-2-quinolones and quinolin-4(1H)-one with a range of substituted benzyl and aliphatic alcohols under solvent free thermal conditions afforded the corresponding monoalkylated products in high to excellent yield and in certain cases produced bis-(3,3′-1-methyl-4-hydroxy)methenes. 相似文献
13.
A series of 3-(N-substituted)-aminoquinolin-2(1H)-ones have been synthesized by the palladium-catalyzed C-N coupling reaction starting from 3-bromoquinolin-2-(1H)-ones. Various nucleophiles including amines, amides, sulfonamides, carbamates and ureas have been used successfully. In all the cases, the reactions take place rapidly in 1,4-dioxane and proceed in good to excellent yield using palladium acetate as a catalyst, Xantphos as a ligand and Cs2CO3 as a base. 相似文献
14.
An efficient synthesis of 4-phenylquinolin-2(1H)-one derivatives has been achieved in a one-pot reaction from N-acyl-o-aminobenzophenones 1a-c (a: acyl=acetyl; b: acyl=propanoyl; c: acyl=heptanoyl) using NaH as a base. Treatment of 1 with NaH provided the quinolones 2a-c with 62-83% yields, whereas the reaction in the presence of alkyl iodide (alkyl=methyl, ethyl, n-octyl) gave the corresponding N-alkylated quinolones 3a-g in 75-95% yields. The alkylation reaction of 4-phenylquinolin-2(1H)-one 2a with alkyl halide gave a mixture of N-alkylated and O-alkylated products. Comparison of IR and NMR data of the N-alkylated and O-alkylated compounds with those of 2a-c indicated that 2a-c exist as the lactam form. 相似文献
15.
Kazumi OkuroHoward Alper 《Tetrahedron letters》2012,53(36):4816-4818
Palladium-catalyzed intermolecular cyclocarbonylation of diethyl (2-iodoaryl)malonates with N-tosylimines produces 4-ethoxycarbonyl-3,4-dihydroisoquinolin-1(2H)-ones in moderate to good yields. This reaction is highly stereoselective. This protocol involves Mannich addition, and subsequent cyclocarbonylation. 相似文献
16.
A combinatorial library of 4-(2-hydroxyaryl)-3-nitro-4H-chromenes was synthesized in high yield by C4-SMe substitution in N-alkyl/phenyl 4-(methylthio)-3-nitro-4H-chromen-2-amines with a variety of phenols. The reaction always provided C2 substitution in the phenol ring, dictated by hydrogen bond interactions between the phenolic hydroxyl group and the nitro group in 3-nitro-4H-chromenes. Reduction of the nitro group with concomitant hydrolysis of the enamine in 4-(2-hydroxyaryl)-3-nitro-4H-chromenes with Zn, Ac2O in AcOH furnished hybrid amino-acid lactone incorporating ortho-tyrosine and phenyl alanine moieties. 相似文献
17.
Min-Ruei Tsai 《Tetrahedron》2004,60(47):10637-10644
An original alternative approach to isoquinolines based on the installation of a benzene nucleus on a performed heterocyclic ring. Synthesis of 3,4-dihydrobenzo[g]isoquinoline-1(2H)-ones and 3,4-dihydroisoquinoline-1(2H)-ones via intramolecular electrophilic cyclization of 3,4-disubstituted lactams is reported. 相似文献
18.
Nazariy T. Pokhodylo 《Tetrahedron》2008,64(7):1430-1434
4,5-Disubstituted and 4-substituted alkyl 2-amino-thiophene-3-carboxylates react with triethyl orthoformate and sodium azide in acetic acid to yield new 2-(1H-tetrazol-1-yl)-4-R1-5-R2-thiophene derivates. It was established that the reaction of these tetrazoles with hydrazine generates the insufficiently studied 2,3-diaminothieno[2,3-d]pyrimidin-4(3H)-one system. It is significant that the reaction mentioned above is the unique tetrazole ring cleavage under the action of hydrazine. 相似文献
19.
Reaction of 2-alkyl-4,5-dichloropyridazin-3(2H)-ones with p-cyanophenol and 2-mercaptopyrimidine in the presence of base gave 2,4,5-trisubstituted-pyridazin-3(2H)-ones 4-9, 2-(4-cyanophenoxy)pyrimidine (10) and 5-cyano-5-(pyrimidin-2-yl)-2,7-dialkyl-5H-dipyridazino[4,5-b:4,5-e]-4H-thiopyran-1,6-diones 11 as a novel heterocycle. 相似文献