Utilization of 2-Ylidene-4-Thiazolidinones in the Synthesis ofHeterocyclic Compounds Part (IV): Synthesis of Thiophene Derivatives (original) (raw)

Reactions of Some New Thienothiophene Derivatives

Molecules, 2011

Facile and convenient syntheses of bisdimethylthieno[2,3-b]thiophen-2,5-diyl bis(oxazole-2-amine), bis(1H-imidazol-2-amine), bis((3a)-H-indole),[1,2-a]pyrimidine), bis(1H-imidazo[1,2-b][1,2,4]triazole) and bis(9H-benzo[d]imidazo[1,2-a]imidazole) derivatives incorporating a thieno[2,3-b]thiophene moiety from the versatile and readily accessible 1,1'(3,4-dimethylthieno[2,3-b]thiophene-2,5-diyl)-bis(2-bromo-ethanone) (1) are described.

Thieno[2,3-b]thiophenes: Part 7. Some Heterocyclization Reactions with Ethyl 3,4-diamino-5-cyanothieno[2,3-b]thiophene-2-carboxylate

Acta chimica Slovenica, 2011

Ethyl 3,4-diamino-5-cyanothieno[2,3-b]thiophene-2-carboxylate (1) was treated with a mixture of carbon disulfide and halo compounds to give the corresponding bisthiazole and bisthiolane derivatives 2-4. Treatment of compound 1 with 2,5-dimethoxytetrahydrofuran gave the corresponding 3,4-dipyrrol-1-ylthienothiophene (5). Condensation of compound 5 with hydrazine afforded the carbohydrazide derivative 6, which was treated with CS2 or PhNCS to afford oxadiazole or triazole derivatives 7a,b. The cycloaddition reaction of compound 5 with CS2 or PhNCS under phase transfer conditions gave 1,4-thiazepino- or 1,4-diazepinothieno[2,3-b]thiophenes 8 and 9, respectively. Basic hydrolysis of compound 1 yielded 3,4-diaminothieno[2,3-b]thiophene (10), which was subjected to react with different reagents to give the corresponding bispyrido- and bispyrrolothieno[2,3-b]thiophenes, and bisarylideneaminothieno[2,3-b]thiophenes 11-15, respectively.

SYNTHESIS OF SOME NEW THIOPHENE-BASED COMPOUNDS AND EVALUATIONS OF THEIR CYTOTOXIC ACTIVITIES

Bull. Chem. Soc. Ethiop. 2023, 37(2), 373-389, 2023

A series of new thiophene derivatives was prepared through nucleophilic substitution reactions of the precursor N-(4-substituted-phenyl)-5-(2-chloroacetamido)-4-cyano-3-methylthiophene-2-carboxamides 4a and 4b with different sulfur and/or nitrogen nucleophilic reagents (namely; mercaptoacetic acid, 2mercaptobenzothiazole, 5-(phenylamino)-1,3,4-thiadiazole-2-thiol, 2-mercapto-4,6-dimethylnicotinonitrile, 3arylazo-4-mercapto-4-(phenylamino)-but-3-en-one derivatives, ammonium thiocyanate, piperidine and/or morpholine). The structures of the prepared thiophene compounds were characterized by spectral analysis. Their cytotoxicity was evaluated against two human cancer cell lines (HepG2 and MCF-7) and indicated promising results. Pretreatment of HepG2 cells with the tested compound 4b sensitized the cells to the cytotoxicity of sorafenib, leading to a significant decrease in the IC50 from 3.9 to 0.5 µM.

Antimicrobial activity of thiophene derivatives derived from ethyl (E)-5-(3-(dimethylamino)acryloyl)-4-methyl-2-(phenylamino)thiophene-3-carboxylate

Chemistry Central Journal

Background: The thiophene nucleus has been recognized as an important entity in the synthesis of heterocyclic compounds with promising pharmacological characteristics. Results: A number of new heterocyclic compounds incorporating thiophene species have been prepared from the titled enaminone via the reaction with different nucleophiles and electrophiles. The structure elucidation of the designed compounds was derived from their spectral information. The results of antimicrobial activity of the prepared compounds revealed that derivatives 7b and 8 exhibited activity comparable to the standard drugs ampicillin and gentamicin for all tested bacteria species. Additionally, compound 3 displayed potent activity against Aspergillus fumigates, whereas compounds 5, 6, and 7a showed good activity against Syncephalastrum racemosum. Conclusions: We have synthesized a number of new thiophene-containing compounds. The results of antimicrobial activity of the prepared compounds revealed that changing the substituents at position-2 of thiophene ring significantly affect their biological activity. The pyridine side chain derivatives in compounds 7a, 7b and 8 showed excellent antimicrobial activity.

Facile and Convenient Synthesis of New Thieno[2,3-b]-Thiophene Derivatives

Molecules, 2010

A facile and convenient synthesis of bis(2-(1H-benzo[d]imidazol-2(3H)ylidene)-3-oxopropanenitrile), bis((3-amino-5-(methylthio)-1H-pyrazol-4-yl)methanone) and bis(2-thioxo-1,2-dihydropyrimidine-5-carbonitrile) derivatives incorporating a thieno-[2,3-b]thiophene moiety via versatile, readily accessible diethyl 3,4-dimethylthieno-[2,3b]thiophene-2,5-dicarboxylate (1) is described.

Design and synthesis of some new thiophene, thienopyrimidine and thienothiadiazine derivatives of antipyrine as potential antimicrobial agents

European Journal of Medicinal Chemistry, 2011

4-acetamide pyrazolone 2 was synthesized by acetylation of 4-amino antipyrine 1 in excellent yield. 4acetamide pyrazolone 2 was exploited as a starting material for the syntheses of hitherto unknown different types of new heterocyclic compounds incorporating the antipyrine moiety which expect highly biological activity against various microorganisms. Thus, Claisen condensation of 4-acetamide pyrazolone 2 with diethyl oxalate have been utility to afford new 4-oxaloacetyl antipyrine 3, which upon hydrazinolysis of the ester function to obtain the acetohydrazide derivative 18 which used as starting material to synthesize 1,2,4-triazol 19 and hydrazone 20 derivatives. 4-aminothiophene carboxylate derivatives 6, 7 were synthesized by utility of Gewald reaction. On the other hand, Michael type addition of the enolate ion of acetyl functions in acetamide pyrazolone 2 to the activated double bond in arylidenemalonoester to furnish pyrane derivative 9 was done. Finally, 4-acetamide pyrazolone 2 was treated with aromatic substituted aldehyde to exhibit thiophenacrylamide derivative 10. Compound 6 gave characteristic reaction for enaminonitriles, thus, the behavior of o-aminoester of 4-aminothiophene carboxylate derivative 6 toward electrophilic reagent, one carbon donars, amide and acid was also investigated to afford the correspondence thiophene derivatives 11,12,13,15 and 16. In addition, treatment of carboxamide derivative 16 with thionyl chloride afforded the thienothiadiazine derivative 17. The characterization of all synthesized compounds was done by elemental analysis and spectral studies. Moreover, all the synthesized compounds were tested against antimicrobial activities by the disc diffusion method, which exhibited higher promising biological activities.

Design and synthesis of some new thiophene and 1,3,4-thiadiazole based heterocycles

Phosphorus, Sulfur, and Silicon and the Related Elements, 2019

The reaction of 3-oxopropanenitriles with phenyl isothiocyanate in DMF containing KOH afforded the corresponding potassium salts. The latter salts were converted into ketene N,S-acetals upon acidification with hydrogen chloride. The reaction of the ketene N,S-acetals with 2-bromo-1-[5methyl-1-(p-tolyl)-1H-1,2,3-triazol-4-yl]ethan-1-one or 3-(2-bromoacetyl)-2H-chromen-2-one gave novel thiophenes in good yields. Treatment of the ketene N,S-acetals with hydrazonyl halides afforded 1,3,4-thiadiazoles in good yields. The stereochemistry of the synthesized compounds was studied.

Synthesis and Antibacterial Activity of Thiophenes

International Journal on Advanced Science, Engineering and Information Technology, 2012

2-[Bis(methylthio)methylene]propanedinitrile 1a reacted in one-pot successively with piperidine, sodium sulfide, chloroacetonitrile, and potassium carbonate to afford 3-amino-5-(1-piperidinyl)-2,4-thiophenedicarbonitrile 2a. Similar reaction using the last three reagents with ethyl 2-cyano-3,3-bis(methylthio)acrylate 1b produced ethyl 4-amino-5-cyano-2-(methylthio)thiophene-3-carboxylate 2b. The synthesized compounds were characterized by using FT-IR, 1 H-NMR, 13 C-NMR, and mass spectral data. Antibacterial activities of the synthesized compounds are also reported.