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1.
Iryna O. Yaremchuk Lyubov V. Muzychka Oleg B. Smolii Olexandr V. Kucher Svitlana V. Shishkina 《Tetrahedron letters》2018,59(5):442-444
The iodolactonization product obtained from methyl 7-allylpyrrolo[2,3-d]pyrimidine-6-carboxylate was used for the synthesis of novel 1,2-dihydropyrrolo[1,2-a]pyrazin-1(2H)-one derivatives, containing carboxamide- and methylamine-groups on the pyrrole ring of the heterocycle. 相似文献
2.
Graham Pattison Dmitry S. Yufit Judith A.K. Howard John A. Christopher 《Tetrahedron》2009,65(43):8844-5866
Pyridazin-3(2H)-one systems have very useful biological properties and have found many applications within the pharmaceutical and agrochemical industries but, in general, synthesis of polysubstituted analogues can be very difficult to achieve. An approach to the syntheses of polyfunctional pyridazinone systems involving sequential nucleophilic substitution reactions of N-aryl and N-THP protected 4,5,6-trifluoropyridazin-3(2H)-ones as the core scaffolds is described. 相似文献
3.
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
4.
A synthetic method to prepare novel phenoxyquinolin-4(1H)-one compounds via cross-coupling of hydroxyquinolin-4(1H)-one with a variety of phenylboronic acids is reported. The reaction is mediated by copper(II) acetate at room temperature in air and is tolerant of several functional groups on the phenylboronic acids. 相似文献
5.
1,5-Di(hetero)arylated-pyridin-2(1H)-one derivatives have been readily obtained in good yields starting from 2-fluoro-5-pyridylboronic acid. The sequence comprises three steps: (i) palladium-catalysed Suzuki-Miyaura reaction; (ii) base-catalysed hydrolysis; (iii) copper-catalysed C-N coupling. X-ray crystal structures are reported for selected pyridin-2(1H)-one derivatives. These compounds are of interest as new scaffolds for drug discovery. 相似文献
6.
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
7.
Irini Akritopoulou-Zanze Alan Whitehead Jan E. Waters Rodger F. Henry Stevan W. Djuric 《Tetrahedron letters》2007,48(20):3549-3552
We report the synthesis of highly functionalized 3,4-dihydroquinolin-2(1H)-ones via sequential Ugi/acrylanilide photocyclization reactions. The [6π]-photocyclization proceeds in excellent yields and with preferential trans-selectivity for the newly formed ring system. 相似文献
8.
Air stable benzodiazepine containing palladacycles were synthesized by a C-H activation reaction and studied by mass spectrometry and X-ray crystallography. Catalytic C-H functionalizations of 1-methyl-5-phenyl-1H-1,4-benzodiazepin-2(3H)-one with diphenyliodonium hexafluorophosphate led to a mixture, which included the starting material and the expected product 1-methyl-5-(2′-biphenyl)-1H-1,4-benzodiazepin-2(3H)-one. 相似文献
9.
A novel and efficient synthesis of N-substituted pyrrolo-pyrazinone derivatives has been developed. A trichloroacetyl group connected to the pyrrole ring was converted into the desired carboxamide derivatives. Promoted by NaH, the pyrrole carboxamide derivatives underwent a tandem reaction with propargyl bromide to afford pyrrolo-pyrazinones with high efficiency under very mild conditions. The mechanism for the formation of the products is discussed and supported by DFT calculations. 相似文献
10.
Stephanie M. Chichetti 《Tetrahedron letters》2007,48(46):8250-8252
The disclosure herein describes the rapid synthesis of novel 6-hydroxypyrimidin-4(1H)-one derivatives via a solvent-free microwave cyclocondensation reaction using di-(2,4,6-trichlorophenyl)malonates and a variety of heterocyclic amines. 相似文献
11.
The synthesis of new pyrrole-functionalized quinoxalines and benzimidazole is described. Our methodology involves the condensation between 2-oxo-2-(1H-pyrrol-2-yl)acetic acid and differently substituted 1,2-phenylene diamines. Depending on the substitution and on the reaction conditions, the synthesis leads to either the pyrrolyl-quinoxaline or -benzimidazole heterocycles. Further insights concerning the structural arrangement of the pyrrolyl-quinoxaline were obtained by solid state analysis, revealing an inverted pyrrole similar to that observed for 2,3-dipyrrolyl quinoxalines. This observation accounts for the fact that strong dipolar interactions or intermolecular H-bonds may govern the structural arrangement in the solid state. 相似文献
12.
Varadhan Krishnakumar Badal Kumar Mandal Fazlur-Rahman Nawaz Khan Euh Duck Jeong 《Tetrahedron letters》2014
A facile and efficient method for the preparation of 3,4,6,7-tetrahydro-9-(1,2-dihydro-2-oxoquinolin-3-yl)-2H-xanthene-1,8(5H,9H)-diones from substituted 2-chloro-3-formylquinoline and 1,3-cyclohexanedione or dimedone in water at 90 °C using parallel synthesizer is reported. The present methodology offers a tandem-cascade methodology, high yield, and operational simplicity. 相似文献
13.
4-Aryl-6-methyl-pyrimidine-2(1H)-one scaffolds of Biginelli type were subjected to C–O cross-coupling reactions using symmetrical diaryliodonium salts under transition metal-free conditions to afford 2-aryloxy pyrimidine derivatives in good to excellent yields. 相似文献
14.
Stewart W. Schneller Jiann-Kuan Luo Ramachandra S. Hosmane 《Tetrahedron letters》1980,21(33):3135-3138
The synthesis of 6-amino-1H-pyrrolo[3,2-c]pyridin-4(5H)-one (3,7-dideazaguanine) from the ammonium chloride promoted reaction of 3-(ethoxycarbonyl)pyrrole-2-acetonitrile and ammonia is reported. Several preliminary reactions which led to this synthetic route are also described. 相似文献
15.
The synthesis of imidazolidin-4-one derivatives of primaquine as potential antimalarial agents is described. The target compounds were synthesized in three steps: (i) condensation of (±)-primaquine with Nα-protected amino acids, (ii) removal of the Nα-protecting group, and (iii) reaction of the N-acylprimaquine with a carbonyl compound: acetone, three cyclic ketones and veratraldehyde. Using 2-formylbenzoic acid in the third step afforded 1H-imidazo[2,1-a]isoindole-2,5(3H,9bH)-diones. All products were isolated in good to excellent yields. Whereas imidazolidin-4-ones were formed as mixtures of all possible diastereomers in equal amounts, 1H-imidazo[2,1-a]isoindole-2,5(3H,9bH)-diones were produced in a stereoselective fashion. The compounds hydrolyse very slowly (t1/2 5-30 d) in pH 7.4 buffer to release primaquine. These primaquine derivatives are being submitted to biological assays, and preliminary results of their antimalarial activity are quite encouraging. 相似文献
16.
Cycloadducts 3 and 4 were treated with tetrabutylammonium fluoride and rapidly suffer cleavage on the three-membered ring to form either pyridin-4(1H)-one or 1H-azepin-4(7H)-one. When R1 is an oxycarbonyl or a 2-pyridyl group and R2 is a negative charge-stabilizing group (cases 3a,b and 4f) the C-C bond cleaves forming products 5. However, when R2=H (case 3c) the ring expands to seven members. When R1 is an acyl group the pyridin-4(1H)-one formation includes an unexpected shift of the carbonyl group. 相似文献
17.
The synthesis of the title compound, which shares its skeleton with a number of biologically active natural products, is described. The key steps are construction of a 3,4-disubstituted furan by a tandem Diels-Alder-retro-Diels-Alder reaction of an alkyne with 4-phenyloxazole, and an intramolecular Friedel-Crafts acylation. 相似文献
18.
The superelectrophilic activation of N-aryl amides of 3-arylpropynoic acids by Bronsted superacids (CF3SO3H, HSO3F) or strong Lewis acids AlX3 (X=Cl, Br) results in the formation of 4-aryl quinolin-2(1H)-ones in quantitative yields. The vinyl triflates or vinyl chlorides may be formed as additional reaction products. The investigated amides in reactions with benzene give 4,4-diaryl 3,4-dihydroquinolin-2-(1H)-ones under the superelectrophilic activation. 4-Aryl quinolin-2(1H)-ones in POCl3 are converted into 4-aryl 2-chloroquinolines. 4-Fluorophenyl-4-phenyl 3,4-dihydroquinolin-2-(1H)-one give N-formylation products in a yield of 79% under the Vilsmeier–Haack reaction conditions. 相似文献
19.
The trifluoromethyl containing heterocycles, 2-hydroxy-4-aryl-3-(thien-2-oyl)-2-(trifluoromethyl)-3,4,7,8-tetrahydro-2H-chromen-5(6H)-one derivatives 4, were synthesized via a one-pot three-component reaction of aldehyde 1 with 1,3-cyclohexanedione 2 and 4,4,4-trifluoro-1-(thien-2-yl)butane-1,3-dione 3 in the presence of a catalytic amount of Et3N. The effect of bases and solvents on the reaction efficiency and yield was briefly investigated. Treatment of 4 with an excess amount of NH4OAc in ethanol afforded 2-trifluoromethyl-1H-quinolin-5-one derivatives 5. Refluxing of 4 with TsOH in CHCl3 gave the corresponding dehydrated products 8. 相似文献
20.
New fluorinated 4H-benzo[h]chromen-4-one and 4H-pyrano[3,2-h]quinolin-4-one derivatives are obtained in moderate to good yields, through a one-pot aldolization-intramolecular SNAr process, from the tetrakis(dimethylamino)ethylene (TDAE) mediated reductive cleavage of two N,N-dimethylamino-bis-chlorodifluoroacetyl substrates in the presence of heteroaryl aldehydes. 相似文献
