Synthesis and study of the fluorescent behavior of 3-pyridinecarbonitriles

Abstract  A series of (2E)-3-(1-chloro-6-methoxy-3,4-dihydronaphthalen-2-yl)-1-(4-aryl)prop-2-en-1-ones (chalcones) have been synthesized by a new synthetic route. The 3-pyridinecarbonitrile derivatives were synthesized by the Michael reaction of malononitrile (in base) and aroylacetonitriles (in acid) with chalcones in one pot. The fluorescent properties and quantum yields of these compounds were studied. Graphical Abstract        

Synthesis and biological activity of (Z) and (E) isomers of 3-(3,4-diaryl-1,2,4-triazole-5-yl)prop-2-enoic acid

Abstract  (Z)-3-(3,4-diaryl-1,2,4-triazole-5-yl)prop-2-enoic acid derivatives were obtained in the course of the reaction of N ³-substituted amidrazones with maleic anhydride, and isomerized into the (E) isomers by heating under reflux in acetic acid solution. The molecular structure of the compounds obtained was confirmed by IR and ¹H NMR spectroscopy, and by X-ray crystallography for (2E)-3-(4,5-diphenyl-4H-1,2,4-triazol-3-yl)prop-2-enoic acid. The antiviral and immunomodulating activity of several of the compounds was examined. Graphical abstract        

A highly efficient and ecofriendly procedure for tetrahydropyranylation of alcohols and phenols in the presence of in-situ generated I2 under heterogeneous and neutral conditions

Abstract  Molecular iodine generated in situ from Fe(NO₃)₃·9H₂O/NaI acts as a highly efficient catalyst for tetrahydropyranylation of various alcohols and phenols with 3,4-dihydro-2H-pyran in almost quantitative yields. The reaction occurs rapidly in dichloromethane at room temperature, and use of toxic molecular iodine is avoided. Graphical Abstract        

C-Furyl glycosides, II: synthesis and antimicrobial evaluation of C-furyl glycosides bearing pyrazolines, isoxazolines, and 5,6-dihydropyrimidine-2(1H)-thiones

Abstract  New C-furyl glycosides bearing pyrazolines, isoxazolines, and dihydropyrimidine-2(1H)-thiones were synthesized in order to increase the number of tested compounds screened for antimicrobial activity. The antimicrobial activity screening showed that the pyrazoline derivatives were the most active compounds. Graphical abstract        

Amino acid derivatives, X [1]: synthesis and antimicrobial evaluation of α-amino acid esters bearing a N1-protected tryptophan side chain

Abstract  A series of peptide derivatives conjugated with N¹-protected tryptophan residue was synthesized. The prepared compounds were tested for antimicrobial activity against four different bacterial species displaying different degrees of antibacterial activities or inhibitory actions. Graphical Abstract        

Two intermediates in the reaction between dibenzoylacetylene and enol systems in the presence of triphenylphosphine in THF/H2O

Abstract  The reaction between dibenzoylacetylene and enol systems, such as acetylaceton or cyclohexane-1,3-dione in the presence of triphenylphosphine in THF/H₂O, leads to 4-acetyl-3-benzoyl-1-phenyl-1,5-hexanedione and 2-hydroxy-3-(2-oxo-2-phenylethyl)-2-phenyl-3,5,6,7-tetrahydro-1-benzofuran-4(2H)-one. Subsequently, these compounds undergo cyclization and elemination reactions in acidic dichloromethane at room temperature to produce known highly functionalized furan derivatives. Graphical abstract        

Chemistry of chromium bis-acetylide complexes

Abstract  Stable paramagnetic Cr(II) and Cr(III) bis(alkynyl) complexes of the type [trans(RC≡C)₂Cr(dmpe)₂] ⁿ⁺ (R = Ph, SiMe₃, SiEt₃, C≡C–SiMe₃ n = 0, 1) were prepared and characterised by NMR, cyclic voltammetry, EPR, magnetic measurements, and X-ray single-crystal diffraction studies. Graphical Abstract        

Synthesis of imidazo[4,5-<Emphasis Type="Italic">a</Emphasis>]acridones and imidazo[4,5-<Emphasis Type="Italic">a</Emphasis>]acridines as potential antibacterial agents

Abstract  New imidazo[4,5-a]acridone derivatives were synthesized from the rearrangement of 3H-imidazo[4′,5′:3,4]benzo[c]isoxazoles. New imidazo[4,5-a]acridines were obtained from the reaction of imidazo[4,5-a]acridones in boiling POCl₃. All of these compounds exhibited antimicrobial activities comparable to streptomycin as reference drug. Graphical abstract        

Heterocycles [<Emphasis Type="Italic">h</Emphasis>]-fused to 4-oxoquinoline-3-carboxylic acid. Part VII: synthesis of some 6-oxoimidazo[4,5-<Emphasis Type="Italic">h</Emphasis>]quinoline-7-carboxylic acids and esters

Abstract  A series of ethyl 2-(substituted)-9-cyclopropyl-4-fluoro-6-oxo-1H-imidazo[4,5-h]quinoline-7-carboxylates has been prepared from ethyl 7,8-diamino-1,4-dihydroquinoline-3-carboxylate via thermally induced reactions with model alkanoic acids or via microwave-assisted cyclocondensation with some arene carboxaldehydes. Acid-catalysed hydrolysis of the resulting ester derivatives furnished the corresponding imidazoquinoline-7-carboxylic acids. The structures of these new acid and ester derivatives are based on microanalytical and spectral (IR, MS, and NMR) data. Graphical abstract        

A one-pot synthesis of functionalized ethyl 1,3-thiazole-5-carboxylates from thioamides or thioureas and 2-chloro-1,3-dicarbonyl compounds in an ionic liquid

Abstract  A simple one-pot synthesis of functionalized ethyl 1,3-thiazole-5-carboxylates from the reaction of 2-chloro-1,3-dicarbonyl compounds with thioureas or thioamides in the presence of 1-butyl-3-methylimidazolium trifluoromethanesulfonate is described. Graphical abstract        

Three-components condensation catalyzed by molecular iodine for the synthesis of 2,4,6-triarylpyridines and 5-unsubstituted-3,4-dihydropyrimidin-2(1H)-ones under solvent-free conditions

Abstract  One-pot, three-components synthesis of 2,4,6-triarylpyridines and 5-unsubstituted-3,4-dihydropyrimidin-2(1H)-ones was performed under solvent-free conditions using molecular iodine as the catalyst in moderate to good product yields. Graphical abstract        

Synthesis of (<Emphasis Type="Italic">E</Emphasis>)- and (<Emphasis Type="Italic">Z</Emphasis>)-3(5)-(2-hydroxyphenyl)-4-styrylpyrazoles

Abstract  An efficient synthesis method for the preparation of a series of new (Z)- and (E)-3(5)-(2-hydroxyphenyl)-4-styrylpyrazoles was developed. The reaction of (Z)- and (E)-3-styrylchromones with hydrazine hydrate afforded the corresponding (Z)- and (E)-3(5)-(2-hydroxyphenyl)-4-styrylpyrazoles, except for nitro derivatives, where both (Z)- and (E)-4′-nitro-3-styrylchromones afforded (E)-3(5)-(2-hydroxyphenyl)-4-(4-nitrostyryl)pyrazoles. The reaction mechanism for these transformations is discussed and the stereochemistries of all products were established by NMR experiments. Graphical abstract        

Synthesis and anti-arrhythmic activity of some piperidine-based 1,3-thiazole, 1,3,4-thiadiazole, and 1,3-thiazolo[2,3-c]-1,2,4-triazole derivatives

Abstract  The reaction of 1-[4-(piperidin-1-yl)benzylidene]thiosemicarbazide with hydrazonoyl chlorides afforded 1,3-thiazole derivatives. Cyclization of two compounds of the latter 1,3-thiazole by means of bromine in the presence of sodium acetate at room temperature gave 1,3-thiazolo[2,3-c]-1,2,4-triazole derivatives. The reaction of 2-cyano-3-(4-piperidin-1-ylphenyl)prop-2-enethioamide with hydrazonoyl chlorides under reflux in ethanol in the presence of triethylamine yielded 1,3-thiazoles. Treatment of 3-oxo-3-(piperidin-1-yl)propanenitrile with phenyl isothiocyanate in DMF, in the presence of KOH, at ambient temperature, resulted in the formation of 3-anilino-3-mercapto-2-(piperidin-1-ylcarbonyl)acrylonitrile which was reacted with hydrazonoyl chlorides to yield the corresponding 1,3,4-thiadiazole derivatives. Some of the newly synthesized compounds had significant anti-arrhythmic activity. Graphical Abstract        

Synthesis of benzohetero[3, 2-<Emphasis Type="Italic">a</Emphasis>]pyrimidines using cyclic β-keto lactone as a building block

Abstract  A novel method for the synthesis of 3-(2-substituted ethyl)-2-methylbenzohetero[3,2-a]pyrimidines in high yield (80–85%) was achieved, which involves a dihydrofuranone intermediate, readily obtained from β-ketolactone to 2-aminobenzoheterocycles. The major advantage of the methodology is the high yield and product purity. Graphical Abstract        

New route to 2-arylthieno[2,3-d]pyrimidin-4(3H)-ones and isolation of the unoxidized intermediates

Abstract  A new route to the synthesis of 2-arylthieno[2,3-d]pyrimidin-4(3H)-ones has been developed through heterocyclization of 2-amino-4,5-dimethylthiophene-3-carboxamide with aromatic aldehydes in boiling glacial acetic acid followed by air oxidation. The unoxidized intermediates, 2-aryl-2,3-dihydrothieno[2,3-d]pyrimidin-4(1H)-ones, are isolated when the reactions are carried out either at room temperature or under a nitrogen atmosphere. Graphical Abstract        

Synthesis and antioxidant activity of some thiazolidin-4-one derivatives

Abstract  4-Fluorobenzaldehyde was used for the preparation of 2-(4-fluorophenyl)thiazolidin-4-one derivatives which were allowed to react with chloroacetonitrile and acrylonitrile to produce 3-(2-(4-fluorophenyl)-4-oxothiazolidine3-yl)acetonitrile and 3-(2-(4-fluorophenyl)-4-oxothiazoledine-3-yl)propanenitrile. Biological evaluation of some of the compounds showed that many had promising antioxidant activity. Graphical Abstract        

Synthesis of novel 4-(2-amino-5-thiazolyl)-pyrimidine-2-amines as potential protein kinase inhibitors

Abstract  A short and efficient sequence for the synthesis of a series of 4-(2-amino-5-thiazolyl)-pyrimidine-2-amines was developed. 1-Phenyl-2-(6-pyrimidinyl)-ethanones, obtained via Weinreb’s methodology, were used in a Hantzsch thiazole cyclization reaction, followed by introduction of the aniline moieties via nucleophilic substitution. Graphical abstract        

Synthesis of 5-spirocyclohexyl-2,4-dithiohydantoin derivatives: a potential anti-leishmaniasis agent

Abstract  A series of spiro-dithiohydantoins were synthesized by heating a mixture of 5-spirocyclohexyl-2,4-dithiohydantoin potassium salt and 3-chloropropanoyl chloride. These compounds were synthesized and evaluated for their activity against five Leishmanial strains in the promastigote stage in vitro. Seventy-two hours inoculation of a variety of products gave an IC ₁₀₀ and average IC ₅₀ values of 1.25 and 0.376 mg/cm³ against all Leishmanial strains tested. Graphical Abstract   An erratum to this article can be found at     

A combined extraction and DFT study on the complexation of K+ with valinomycin

Abstract  From extraction experiments in the two-phase water–nitrobenzene system and γ-activity measurements, the stability constant of protonated tetraethyl p-tert-butylcalix[4]arene tetraacetate in nitrobenzene saturated with water was determined. By using DFT calculations, the most probable structure of the tetraethyl p-tert-butylcalix[4]arene tetraacetate·H₃O⁺ complex species was derived. Graphical Abstract        

Synthesis and biological evaluation of 5-substituted benzo[b]thiophene derivatives as anti-inflammatory agents

Abstract  5-Aminobenzo[b]thiophene-2-carboxylic acid was converted to the corresponding 5-(2-chloroacetamido)benzo[b]thiophene-2-carboxylic acid by reaction with chloroacetyl chloride. This acetamido product was treated with different alkyl, cycloalkyl, aryl, and heterocyclic amines to afford a series of C5-substituted benzo[b]thiophenes. These compounds were found to possess potent anti-inflammatory activity. Graphical abstract