Synthesis of Some New Thieno[2,3-b]pyridines,Pyrimidino[4′,5′:4,5]thieno[2,3-b]-pyridines,and 2,3-Dihydro-1,3,4-thiadiazoles

Thieno[2,3-b]pyridines were synthesized from 6-benzofuran-2-yl-4-phenyl-2-sulfanylpyridine-3-carbonitrile and each of chloro acetone, ethyl chloroacetate, ω -bromoacetophenone, and chloroacetonitrile. These compounds were conveniently converted into novel pyrido[4′,5′:4,5]thieno[3,2-d]pyrimidines. Also, 2,3-dihydro-1,3,4-thiadiazole was synthesized from hydrazonoyl halides and 2-benzofuran-2-yl-3-(phenylamino)-3-thioxopropanenitrile. The structures of the products have been elucidated by elemental analyses, spectral data studies, and alternative syntheses whenever possible. The newly synthesized compounds were tested towards microorganisms.     

Synthesis of Benzo[4,5]furo[3,2-b]thieno[2,3-d]pyridines —Derivatives of a New Heterocyclic System

Russian Journal of Organic Chemistry - Methyl 2-(bromomethyl)thiophene-3-carboxylates reacted with substituted 2-hydroxybenzonitriles to give methyl...     

Synthesis and characterization of some new pyridines,thieno[2,3-b] pyridines and pyrido[3′,2′:4,5]thieno[3,2-d]pyrimidine-4(3H)-ones bearing styryl moiety

3-Cyano-5-ethoxycarbonyl-6-methyl-4-styrylpyridine-2(1H)-thione ( 3 ) was prepared by reaction of 2-cyano-5-phenylpenta-2,4-dienethioamide ( 2 ) with ethyl acetoacetate or by multicomponent reaction of cinnamaldehyde ( 1 ), cyanothioacetamide and ethyl acetoacetate in a moderate yield. Reaction of compound 3 with some N-aryl-2-chloroacetamides, in the presence of sodium acetate, gave the corresponding 2-(N-arylcarbamoylmethylsulfanyl)-3-cyano-5-ethoxycarbonyl-6-methyl-4-styrylpyridines 4a-f . When compounds 4a-f were subjected to Thorpe-Ziegler reaction conditions, they converted into the corresponding 3-amino-5-ethoxycarbonyl-2-(N-arylcarbamoyl)-6-methyl-4-styrylthieno[2,3-b]pyridines 5a-f . Compounds 5a,e,f were reacted, in turn, with 2,5-dimethoxytetrahydrofuran to furnish the corresponding 3-(pyrrol-1-yl)thieno-pyridines 6a,e,f . Reactions of 5a-f with triethyl orthoformate or nitrous acid were also carried out and their products were identified. Structural formulas of all synthesized compounds was characterized and confirmed on the basis of their elemental and spectral analyses.     

Engaging thieno[2,3-b]indole-2,3-dione for the efficient synthesis of spiro[indoline-3,4′-thiopyrano[2,3-b]indole] by reaction with N-substituted isatilidenes

A simple and efficient method, proceeding through a new mechanistic pathway, for the synthesis of spiro[indoline-3,4-thiopyrano[2.3-b]indole derivatives have been developed by exploiting the reaction of thieno[2,3-b]indole-2,3-dione with N-substituted isatilidenes. The compounds synthesized have been screened for antibacterial activity. The generality of the reaction and mechanistic rationale are presented.     

New convenient synthesis of substituted 6,9-dihydropyrido[3′,2′:4,5]thieno[3,2-b]pyridines and 6,9-dihydropyrido[3′,2′:4,5]thieno[3,2-d]pyrimidines

1,4-Dihydro-3-cyano-2-pyridinethiolates react with 2-bromo-l-(4-bromophenyl)ethylidenemalononitrile or N-cyanochloracetanudine to give 6, 9-dihydropyrido[3, 2': 4, 5]thieno[3. 2-b]pyridines or 6, 9-dihydropyrido-[3.2:4.5Jthieno(3,2-d]pyrimidines, respectively.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 553–556, April, 1996.     

Thieno[2,3-b]pyridine-2-carbohydrazide in Polyheterocyclic Synthesis: The Synthesis of Pyrido[3′,2′:4,5]thieno[3,2-d]pyrimidine,Pyrido[3′,2′:4,5]thieno[3,2-d][1,2,3]triazine,and Pyrazolyl,Oxadiazolylthieno[2,3-b]pyridine Derivatives

Pyrdine-2(1H)-thione 1 reacted with ethyl chloroacetate 2 to give 2-S-ethoxy-carbonylmethylpyridine derivative 3, which could be cyclized into thieno[2,3-b]-pyridine-2-carbohydrazide derivative 5 by boiling with hydrazine hydrate. The latter compound reacted with cinnamonitrile derivatives 6a, b, triethylorthoformate, formic acid, dimethylformamide-dimethylacetal, and diethyl carbonate to give the corresponding shiff base 7a, b and pyrido[3′,2′;-4,5]thieno[3,2-d]pyrimidine derivatives 10–13 in respective manner. On the other hand, compound 5 also reacted with carbondisulphide and phenyl isothiocyanate to afford the corresponding 2-(1,3,4-oxadiazolo-2-yl)thieno[2,3-b]pyridine derivatives 18 and 22. Finally, compound 5 reacted with some β-dicarbonyl compounds, such as ethyl acetoacetate, acetylacetone and ethyl β-arylazoacetoacetate, to yield the corresponding 2-(pyrazol-1-yl-carbonyl)thieno[2,3-b]pyridine derivatives 24, 25, and 27 respectively.     

One-Pot Synthesis of Thieno[2,3-b]pyridine and Pyrido[3′,2′:4,5]thieno[3,2-d]pyrimidine Derivatives

Russian Journal of Organic Chemistry - 2-Acyl-4,5,6-trialkyl-3-aminothieno[2,3-b]pyridines,...     

Synthesis and antimicrobial evaluation of the novel heteroannulated furo[3′,2′:6,7]chromeno[2,3-b]pyridines: Part 1

The chemical behavior of 4,9-dimethoxy-5-oxo-5H-furo[3,2-g]chromene-6-carbonitrile ( 1 ) was investigated toward some acyclic and cyclic active methylene ketones namely acetylacetone, ethyl acetoacetate, ethyl benzoylacetate, acetoacetanilide, dimedone, indanedione, pyrazolidine-3,5-dione and 5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one, barbituric acid and 1-allylthiobarbituric acid, and hippuric acid. A variety of novel heteroannulated furochromenopyridines were efficiently synthesized through a cascade reactions between 4,9-dimethoxy-5-oxo-5H-furo[3,2-g]chromene-6-carbonitrile ( 1 ) and the carbon nucleophilic reagents. Structures of the new products were inferred based on their analytical and spectral data.     

Pyridazines,LIV: On the synthesis of pyridazine-fused S-heterocycles: Thieno[2,3-c]pyridazine,pyrimido[4′,5′:4,5]thieno[2,3-c]pyridazine,and pyridazino[3,4-b][1,4]benzothiazine

Summary Starting from 3-chloro-4-pyridazinecarbonitrile (1), the thienopyridazine derivatives2 and3 were prepared. Condensation of3 with triethyl orthoformate afforded the novel tricyclic system4. Reaction of1 with 2-aminothiophenol, followed by treatment with NaH/DMSO was found to give the diaza-phenothiazine6 instead of the expected condensed thiazepine.Dedicated with best wishes to Prof. Dr. G. Zigeuner on the occasion of his 70^th anniversary     

New approaches to the synthesis of functionally substituted pyrido[3′,2′:4,5]thieno[3,2-b]pyridines and the structure of the products obtained

Substituted pyrido,[3',2':4,5]thieno[3,2-b]pyndines were obtained by the reaction of 3-amino-2-benzoylthieno [2,3-b]pyridines with malononitrile and the reaction of 3-cyanopyridine-2(IH)-thiones with 2-aryl-3-bromo-I,I-dicyanopropene. 2-Amino-4-(4-bromophenyl)-7, 9-dimethyl-3-cyanopyrido [3',2':4,5]thieno[3, 2-b]-pyridine was used for the synthesis of a derivative of pyrido[3",2":4', 5']thieno[2',3':5,6]pyrido[2,3-d]-pyrimidine. The structure of these compounds was confirmed by spectral data and x-ray diffraction structural analysis.Deceased.     

A new phenanthro [2,3-b] furan from Pleione bulbocodioides

A novel phenanthro[2,3-b]furan 1,named(3-hydroxy-9-(4′-hydroxy-3′-methoxypheny1)-11-methoxy-5,6,9,10-tetrahydro- phenanthro[2,3-b]furan-10-yl)methyl acetate,and two known phenolic compounds were isolated from the tubers of Pleione bulbocodioides(Franch.)Rolfe.Their structures were elucidated by spectroscopic methods.     

Syntheses with heterocyclic β-enaminonitriles: A facile preparation of polyfunctionally substituted thiophene,thieno[3,2-b]pyridine and thieno[3,2-d]pyrimidine derivatives

Summary A convenientGewald synthesis of 3,5-diaminothiophene-2-carbonitrile derivatives (2) is reported. The synthetic potential of the -enaminonitrile moiety in2 has been explored; it proved to be a promising candidate for the synthesis of polyfunctionally substituted thieno[3,2-b]pyridines and thieno[3,2-d]pyrimidines.

---

Synthesen mit heterocyclischen -Enaminonitrilen: Eine einfache Methode zur Herstellung polyfunktionell substituierter Thiophen-, Thieno[3,2-b]pyridin- und Thieno[3,2-d]pyrimidinderivate

Zusammenfassung Eine bequeme Methode zur Herstellung von 3,5-Diaminothiophen-2-carbonitril-Derivaten (2) nachGewald wird vorgestellt. Das synthetische Potential der -Enaminonitrilfunktion von2 wurde untersucht.2 ist ein geeignetes Ausgangsmaterial für die Synthese polyfunktionell substituierter Thieno[3,2-b]pyridine und Thieno[3,2-d]pyrimidine.

     

A convenient synthesis of pyrrolo[2,3-b]pyridines and pyrido[2′,3′:5,4]pyrrolo[2,3-d]pyrimidines

2-Chloro-6-ethoxy-4-phenylpyridine-3,5-dicarbonitrile was taken as versatile building block that allows the synthesis of 1H-pyrrolo[2,3-b]pyridine, thieno[2,3-b]pyridine and pyrido[2′,3′:5,4]pyrrolo[2,3-b]pyrimidine systems. Some of the synthesized compounds were screened as antibacterial agents.     

Dianthra[2,3-b:2',3'-f]thieno[3,2-b]thiophene (DATT): synthesis, characterization, and FET characteristics of new π-extended heteroarene with eight fused aromatic rings

A novel highly π-extended heteroarene with eight fused aromatic rings, dianthra[2,3-b:2',3'-f]thieno[3,2-b]thiophene (DATT), was selectively synthesized via a newly developed synthetic strategy, fully characterized by means of single crystal X-ray structural analysis, and examined as an organic semiconductor in thin film transistors. Even with its highly extended acene-like π-system, DATT is a fairly air-stable compound with IP of 5.1 eV. Single crystal X-ray structural analysis revealed its planar molecular structure and the lamella-like layered structure with typical herringbone packing. Theoretical calculations of the solid state electronic structure based on the bulk single crystal structure suggest that DATT affords almost comparable intermolecular orbital couplings between HOMOs (t(HOMO)) with those of dinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophene (DNTT), implying its good potential as an organic semiconductor for organic field-effect transistors. In fact, field-effect mobilities as high as 3.0 cm(2) V(-1) s(-1) were achieved with vapor-processed DATT-based devices, which is comparable with that of DNTT-based devices. The molecular ordering of DATT in the thin film state, however, turned out to be not completely uniform; as elucidated by in-plane and out-of-plane XRD measurements, the face-on molecular orientation was contaminated in the edge-on orientation, the former of which is not optimal for efficient carrier transport and thus could limit the mobility.     

Synthesis of pyrido[3′,2′:4,5]thieno[2,3-c]cinnolines — A new heterocyclic system

Pyrido[3,2:4,5]thieno[2,3-c]cinnolines, new heterocyclic compounds, were obtained in three steps: 1) alkylation of 3-cyanopyridine-2(1H)-thiones by o-nitrobenzyl bromide to give 2-(o-nitrobenzyl)thio-3-cyanopyridines, 2) closure of the thiophene ring in these intermediates to give 3-amino-2-(o-nitrophenyl)thieno[2,3-b]pyridines, and 3) closure of the pyridazine ring by condensation of the amino and nitro groups in triethyl phosphite, leading to the final heterocyclic system.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 104–109, January, 1998.     

Synthesis of benzothieno[2,3-b]thiophenes, [2,3-b:3′,2′-d]-dithienothiophenes and their selenium derivatives via electrophilic cyclization and McMurry cyclization

Benzothieno[2,3-b]thiophenes, [2,3-b:3′,2′-d]-dithienothiophenes, and their selenium derivatives were synthesized in good yields from readily available 3-ethynyllithio-benzo[b]thiophenyllithio compounds, sulfur or selenium, and 2 equiv of acid chlorides. Two heteroarene rings were constructed by a twofold cyclization via an acid chloride-induced electrophilic ring closing and the McMurry cyclization using Zn/TiCl₄ reagents.     

呋喃[2,3-b]喹啉衍生物的合成及其生物活性研究进展

呋喃[2,3-b]喹啉骨架作为目前发现数目最为庞大的一类天然呋喃喹啉结构,因其丰富的结构与良好的生物活性,吸引了大量研究者的关注。近年来,不仅许多新的天然呋喃[2,3-b]喹啉不断从自然界中被发现,而且基于生物活性研究的衍生物制备也得到蓬勃发展。为了充分利用这一宝贵天然资源,为活性天然产物的结构改造提供一定指导与参考,本文对近二十年来呋喃[2,3-b]喹啉衍生物的合成以及相关生物活性研究进行了总结,并展望其前景。     

Synthesis of novel [1,2,3]triazolo[4′,5′:3,4]pyrrolo[1,2-a]thieno[2,3-d] pyrimidines: Potent EGFR targeting anti-breast cancer agents

In this study, we designed and synthesized several novel fused [1,2,3]triazolo [4′,5′:3,4]pyrrolo[1,2-a]thieno[2,3-d]pyrimidine derivatives using in a single [3 + 2] reaction cycloaddition reaction of 3-(3-iodoprop-2-yn-1-yl)thieno[2,3-d]pyrimidin-4(3H)-one ( 4 ) followed by C-C bond coupling with various aryl azides in a PEG-400 medium. All of the newly synthesized compounds were evaluated in vitro for EGFR kinase inhibitory action as well as anti-breast cancer activity against MDA-MB-231 and MCF-7 breast cancer cell lines. When compared to the reference molecule, erlotinib, the majority of the compounds demonstrated adequate efficacy. The most promising compounds, 5g and 5i , demonstrated excellent anticancer activity against both cancer cell lines, with IC₅₀ values ranging from 04.17 ± 0.55 to 8.65 ± 0.89 μM, respectively, as well as excellent kinase inhibitory activities (EGFR: IC₅₀ = 0.467 ± 0.063 and 0.412 ± 0.081 μM). The in silico studies of five potent compounds 5f , 5g , 5h , 5i , and 5k were also carried out to identify the interactions against the EGFR receptor and found that the energy calculations were covenant with the obtained IC₅₀ values.     

噻吩并[2,3-b]吡啶类化合物的合成及生物活性

用邻氨基噻吩腈与不同结构的二羰基化合物反应,合成了新的多取代噻吩并吡啶类衍生物4-氨基-5-取代羰基噻吩并[2,3-b]吡啶-6-酮。用元素分析、红外光谱、核磁共振氢谱和质谱等测试技术对所合成化合物的结构进行了表征。初步生物活性测试表明,该类化合物有较好的杀菌活性和一定的除草活性。     

噻吩并[2,3-b]吡啶化合物的合成及应用

噻吩并[2;3-b]吡啶;生物活性;医药;农药;合成