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1.
马云  钱长涛  谢美华  孙杰 《中国化学》2000,18(3):377-383
Imino Diels-Alder reaction of imines with 2,3-dihydrofuran or 3,4-dihydro-2H-pyran proceeded smoothly in the presence of a catalytic amount (0.5 mol %) of ytterbium triflate to afford furo[3,2-c]- and pyrano[3,2-c] quinolines conveniently in high yield.  相似文献   

2.
Research on Chemical Intermediates - The widespread biological properties of dihydropyrano[3,2-c]chromenes, 2-amino-4-aryl-4H-benzo[h]chromenes, and 3-amino-1-aryl-1H-benzo[f]chromenes have led to...  相似文献   

3.
Readily available (chlorocarbonyl)phenyl ketene and a varied set of β-ketoamides were reacted in a one-step procedure to produce 2-pyrone derivatives. β-Ketoamide derivatives are versatile intermediates for the synthesis of heterocyclic compounds. For instance, 1-morpholino-3-phenyl-1,3-propanedione, 1-phenyl-3-piperidino-1,3-propanedione, 1-phenyl-3-pyrrolidino-1,3-propanedione, 1-piperidino-1,3-butanedione, 1-morpholino-2-phenyl ethanone were used in these reactions to produce 2-pyrone derivatives. In addition, the preparation of 4-hydroxy-3-phenylthiochromeno[4,3-b]pyran-2,5-dione derivatives and 4-hydroxy-7-methyl-3-phenyl pyrano[3,2-c]chromeno-2,5-dione were described. For the synthesis of these compounds 4-hydroxy-2H-thiochromen-2-ones and 4-hydroxy-8-methyl-2H-chromen-2-one were reacted with (chlorocarbonyl)phenyl ketene and the final products were isolated in good yields.  相似文献   

4.
Abstract

A task-specific ionic liquid, [H3N+–CH2–CH2–OH][CH3COO?], was successfully applied as an efficient and reusable catalyst for the one-pot domino to approach to dihydropyrano[3,2-c]chromene derivatives with atom economy in a condensation reaction of 4-hydroxycoumarin, aldehydes, and malononitrile in a combinatorial fashion. The reaction gave excellent yields within short reaction times at room temperature under solvent-free grinding conditions. The products and ionic liquid could be conveniently separated from the reaction mixture, indicating that the whole process was performed as a green chemical transformation.   相似文献   

5.
In this study, a novel Cu-immobilized ionic liquid (IL)was designed, characterized, and employed as both promoter and solvent in the synthesis of some dihydropyrano[2,3-c]pyrazoles. The synthesized ionic liquid was characterized by 1H NMR, 13C NMR, FTIR, ICP and EDX analysis and showed high catalytic activity to proceed the synthesis of bioactive dihydropyrano[2,3-c]pyrazole derivatives. This method has the advantage of using the IL as a green medium for the synthesize of the products in high to excellent yields within short reaction times.  相似文献   

6.
Different pyrazolone derivatives were prepared by microwave irradiation and ultrasound assisted methods besides the traditional ones. They were used for synthesis of some derivatives of spiropiperidine-4,4′-pyrano[2,3-c]pyrazole, dihydropyrano[2,3-c]pyrazole, pyrazole-4-carbothioamide, 4-(2-oxo-1,2-diphenylethylidene)-1H-pyrazol-5(4H)-one, azopyrazole, arylmethylenebis-1H-pyrazol-5-ol and araylidene-1H-pyrazol-5(4H)-one via reactions with different reagents applying the ultrasound method in some cases.  相似文献   

7.
A facile and highly efficient protocol for the synthesis of 1,8-dioxo-octahydroxanthene derivatives was achieved through cascade Knoevenagel-Michael condensations and cyclo-dehydration reaction utilizing tetrachlorosilane(TCS) as catalyst under mild conditions.Reaction of the titled compounds with TCSNaN3 to give novel functionalized pyrano[3,2-c]tetrazolo[1,5-a]azepine derivatives is also described.  相似文献   

8.

In the current study, magnetite-silica core–shell nanoparticles modified with Cu-salen complex (Fe3O4@SiO2-imine/phenoxy-Cu(II)) was utilized as a heterogeneous catalyst for the one-pot multicomponent synthesis of 1H-pyrazolo[1,2-b]phthalazine-5,10-dione and dihydropyrano[3,2-c]chromene derivatives under solvent-free conditions, without using any harmful organic reagents/solvent. The current synthetic protocol demonstrates that the reactions proceeds to completing step, leading to the successful synthesis of high purity compounds. Advantages of this method include easy purification, reusability of the catalyst, green and mild procedure and synthesis of new derivatives in high yields within short reaction time.

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9.
One pot synthesis and characterization of new 5-[2′-(1H-tetrazol-5-yl)-biphenyl-4-ylmethyl]-4,5,6,7-tetrahydro-thieno[3,2-c]pyridines (3a–k) using amides (2a–k) were reported. The prepared 5-[2′-(1H-tetrazol-5-yl)-biphenyl-4-ylmethyl]-4,5,6,7-tetrahydro-thieno[3,2-c]pyridine (3a) is a bioisostere of 4′-(6,7-dihydro-4H-thieno [3,2-c]pyridin-5-ylmethyl)-biphenyl-2-carboxylic acid (1), having good in vivo antithrombotic activity compared with Clopidogrel. The new tetrazole derivatives (3a–k) were screened for their in vitro activity as platelet aggregation inhibitors.  相似文献   

10.
[reaction: see text] Synthetic approaches to a variety of thioisomunchnones derived from uracils and uridine are described, as well as their properties and cycloaddition tendencies. The anhydro-3-hydrocy-2-phenyl-6-(2',3',5'-tri-O-benzoyl-beta-D-ribofuranosyl)thiazolo[3,2-c]pyrimidine-5(6H)-on-4-ium hydroxide represents a novel class of mesoionic nucleosides.  相似文献   

11.
An efficient and green protocol for the synthesis of dihydropyrano[2,3-c]chromene derivatives by one-pot, three component coupling reaction of aromatic aldehyde, malononitrile, and 3-hydroxycoumarin has been developed using nano-structured ZnO as the catalyst. The formation of self-assembled organic nanofiber arising from low-molecular-weight molecules has also been performed. The optical properties of the nano-structured organic molecules were studied.  相似文献   

12.
Variously substituted indolo[2,3-c]quinolines, benzofurano[2,3-c]quinolines and their positional isomers indolo[3,2-c]quinolines and benzofurano[3,2-c]quinolines respectively, were prepared from both indole and quinoline derivatives by intramolecular nucleophilic displacement of aromatic fluorine. The formation of an indolo[2,3-d]benzazepine was also observed.  相似文献   

13.
With the aim of obtaining new antitumor drugs more active than previously described 11H-indolo[3,2-c]quinoline-1,4-diones and 7,8,9,10-tetrahydro-11H-indolo[3,2-c]quinoline-1,4-diones, the synthesis and activities of a series of 3-substituted 11H-pyrido[3',4':4,5]pyrrolo[3,2-c]quinoline-1,4-diones and of 7,8,9,10-tetrahydro-11H-pyrido-[3',4':4,5]pyrrolo[3,2-c] quinoline-1,4-diones were studied. Some quinones were more cytotoxic in vitro towards L1210 leukemia cells but were not active in vivo towards murine P388 leukemia.  相似文献   

14.
在1,4-二氮杂二环[2.2.2]辛烷(DABCO)促进下,以水为反应介质,通过3-溴乙酰基-4-羟基-1-甲基-2-喹啉酮与芳香醛的亲核取代、分子内环化及消除的串联反应,合成了9个新型的呋喃并[3,2-c]喹啉酮类化合物,其结构经~1H NMR,~(13)C NMR,IR,MS(ESI)和元素分析表征。  相似文献   

15.
This review describes the synthesis of thieno[2,3-c]pyridazine, thieno [3,2-c]pyridazine, thieno[2,3-d]pyridazine and thieno[3,4-d]pyridazine derivatives and their reactions.  相似文献   

16.
It has been shown that the most efficient catalysts for the synthesis of 4,5,7-trimethyl-4,5,6,7-tetrahydropyrrolo[3,2-c]pyridine from 1,2,5-trimethylpyridin-4-one and acetylene under Trofimov conditions are rubidium and potassium hydroxides. Use of Triton B or a mixture of trimethylbenzylammonium chloride with rubidium hydroxide as catalyst gives O-alkylated oxime. Their configurations and conformations were established through separation of the individual isomers of 1-vinyl-4,5,7-trimethyl-4,5,6,7-tetrahydropyrrolo[3,2-c]pyridines. Acetyl nitrate nitration of the cis isomer of this compound gave the 2- and 3-nitro derivatives. Similar nitration of 4,5,7-trimethyl-4,5,6,7-tetrahydropyrrolo[3,2-c]pyridine gave the 2-nitro-7-hydroxy derivative.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1375–1380, October, 1991.  相似文献   

17.
A convenient and efficient synthesis of substituted 2,3-dihydrothieno[3,2-c]pyridin-4(5H)-ones has been developed and relies upon a domino reaction of dimethylaminopropenoyl cyclopropanes initiated by Lawesson's reagent. A mechanism involving regioselective thionation, ring-enlargement, and an intramolecular aza-cyclization sequence is proposed. This protocol was utilized as a one-pot route to thieno[3,2-c]pyridin-4(5H)-ones with DDQ as an oxidant.  相似文献   

18.
A convenient synthesis of the benzo[h]furo[3,2-c]quinoline ring is reported. Hydrogenation of dienic adducts 5 gives comppounds 6. Successive pyrolysis and alcaline hydrolysis of 6 provide diacids 9 which in the presence of anhydrous ammonium acetate and acetic acid undergoes intramolecular cyclisation to give benzo[h]furo[3,2-c]quinolone derivatives 12. The modulation of the 7-carboxy group and introduction of amino groups in the 6 position are then realized.  相似文献   

19.
Pyrano[3,2-c]quinoline alkaloids 3 , suitable precursor for photobiomimetic dimerisations, are available by ptc-reactions of 4-hydroxyquinoline-2-ones 1 with 3-chloro-3-methylbut-1-yne, as byproducts uro[3,2-c]-quinoline-2-one is isomeres 5 are found. In the synthesis of flindersine ( 3a ) additionally the oxazolo[3,2-a]quinolin-5-one 4 could be isolated, while in the preparation of N-methylflindersine ( 3b ) a bis-(N-methyal-4′-hydroxyquinolin-2′-one-3′-yl)isopentene ( 7 ) was identified. Alkaloid dimers, which may be formed from the intermediates 6 , were not present. The structure of 7 confirms reaction pathways, discussed previously. Haplophylline ( 3c ) is synthesized for the first time by N-alkylation a of 3a with 3-methylcrotonyal chlormethyl ester.  相似文献   

20.
Meng-Jian Yao  Zhi Guan 《合成通讯》2013,43(15):2073-2078
A one-pot, three-component reaction of 4-hydroxyquinolin-2(1H)-one, malononitrile, and various aldehydes for the synthesis of 2-amino-3-cyano-1,4,5,6-tetrahydropyrano[3,2-c]quinolin-5-one derivatives is reported. The reaction is performed without any catalysts in a mixed solvent of water and ethanol to give products in good yields. The present method provided a clean, simple, and economical alternative for the synthesis of potential biologically active pyranoquinoline derivatives.

Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.  相似文献   

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