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We report a green and efficient method for the synthesis of 4-arylidene-1-(4-phenylselenazol-2-yl)-3-methyl-1H-pyrazole-5(4H)-ones from the condensation of phenacyl bromide, selenosemicarbazide with ethyl acetoacetate and aryl aldehyde in acetic acid using sodium acetate as a base. [ABSTRACT FROM AUTHOR]

An efficient synthesis of 3-phenyl-1-(6-phenyl-7H-[1,2,4] triazolo[3,4-b][1,3,4]thiadiazin-3-yl)-1H-pyrazol-5-amines was accomplished by a simple, atom-economical, and multicomponent approach. Reaction of 4-amino-5-hydrazinyl-4H-1,2,4-triazole-3-thiol with various phenacyl bromides and benzoylacetonitriles in ethanol and catalytic amount of acetic acid afforded the titled compounds. The structures of newly synthesized compounds were confirmed by their analytical and spectral (IR, ¹H-NMR, 13C-NMR, and Mass) data. [ABSTRACT FROM AUTHOR]

A greener approach for the synthesis of 4-oxo-4,5,6,7-tetrahydro indole derivatives has been achieved through Wang-OSO3H-mediated three-component reaction involving dimedone, phenacyl bromide, and primary amine in water. A variety of indole derivatives were prepared using this operationally simple and straight forward methodology in acceptable yields. [ABSTRACT FROM AUTHOR]

The behavior of thioacetoacetanilide(1)and/or α-arylhydrazono-thioacetoacetanilides4toward many different α-halocarbonyl compounds was demonstrated. Thus, reactions of1with α-bromoketones (bromoacetone and phenacyl bromide) and hydrazonoyl bromides afforded the corresponding thiazole, thiophene and 1,3,4-thiadiazole derivatives, respectively. The synthesis and reactivity of thiazolidin-5-one2toward aromatic diazonium chlorides and aromatic aldehydes were described. Most of the synthesized compounds were screened for their antibacterial and antifungal activities and showed accepted antimicrobial activities with respect to the control drugs. [ABSTRACT FROM AUTHOR]

The article describes a convenient and efficient synthetic route for the construction of 2-aroylbenzofuran-3-ols from readily available diverse methyl salicylates and phenacyl bromides using K2CO3as catalyst in dimethylformamide as solvent at room temperature. The reaction involves two steps, which occur in quick succession within 1 h to deliver the product with reasonably high yields. All the synthesized 2-aroylbenzofuran-3-ols (4a–u) were subjected for their antimicrobial studies, and some of these have shown prominent activity. [Supplementary materials are available for this article. Go to the publisher's online edition ofSynthetic Communications®for the following free supplemental resource(s): Full experimental and spectral details.] [ABSTRACT FROM PUBLISHER]

Reaction of coumarin-3-carboxylic acid with 3,5-di mercapto-4-amino-s-triazole in POCl3to generate 3-(3-mercapto-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazol-6-yl)-2H-chromen-2-one (3). Reaction of3with different substituted phenacyl/benzyl/allyl bromides in anhydrous ethanol gave corresponding 3-(3-(phenacyl/alkyl/benzylthio)-[1,2,4]triazolo[3,4-b][1,3,4] thiadiazol-6-yl)-2H-chromen-2-ones5. The structures of newly prepared compounds were confirmed by their analytic and spectral data. [ABSTRACT FROM PUBLISHER]

An efficient and convenient protocol of broad scope for the synthesis of quinoxaline by cyclization-oxidation of phenacyl bromide with equimolar amount of phenylenediamine at room temperature catalyzed by thiamine in the form of N-heterocyclic carbene (NHC). High efficiency, inexpensiveness, and non-toxicity are the interesting features of the catalyst, which make it eco-friendly and highly attractive. [ABSTRACT FROM AUTHOR]

An efficient and general method has been described for the synthesis of imidazo[2,1-b]-1,3,4-thiadiazole by the reaction of 2-aminothiadiazoles with phenacyl bromides in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO). The method is suitable for the synthesis of functionalized imidazothiadiazoles. [ABSTRACT FROM AUTHOR]

A facile, one-pot, three-component bis heterocyclized reaction for the synthesis of hydrazonothiazolyl-pyrazolones has been described. Reaction of phenacyl bromides or 3-(2-bromoacetyl)coumarins, with thiosemicarbazide and ethyl 2-(2-arylhydrazono)-3-oxobutanoates in AcOH/NaOAc, gave the corresponding products in good yields. All the synthesized compounds were characterized by their analytical and spectral data. [ABSTRACT FROM AUTHOR]

Silica phosphoric acid has been found to be an efficient catalyst for the synthesis of 2-amino/anilino-5-aryl-1,3,4-thiadiazine bromide derivatives from the reaction of thiosemicarbazide and α-bromoketones in acetonitrile at room temperature. The catalyst can be reused for four times without any significant loss of catalytic activity. The experimental procedure is simple, and the products are obtained in high yield. [ABSTRACT FROM AUTHOR]

A novel, one-pot, multicomponent synthesis of 4-arylidene-3-methyl-1-(4-arylthiazol-2-yl)-1H-pyrazol-5(4H)-ones is described using phenacyl bromides, thiosemicarbazide, ethylacetoacetate, and aryl aldehydes. This synthesis involves simultaneous formation of two heterocycles like thiazole and pyrazolone along with condensation of active methylene group by aldehydes via Knoevenagel reaction. The methodology is mild, efficient, and high yielding. GRAPHICAL ABSTRACT[image omitted] [ABSTRACT FROM AUTHOR]

[image omitted] A simple and convenient protocol is described for the preparation of 2,4-disubstituted thiazoles via a condensation reaction of α -halo carbonyl compounds with thiourea or thioacetamide at room temperature, under grinding, in good yields. [ABSTRACT FROM AUTHOR]

The reaction between phenacyl bromide and 2-mercaptobenzimidazole has been studied in 12 different protic and aprotic solvents. The kinetic study shows that the reaction is second-order with first-order dependence each on (phenacyl bromide) and (2-mercaptobenzimidazole). Analysis of rate data shows that there is no direct correlation between the rate constant and dielectric constant of the solvent. Correlation of rate data with different solvent parameters like hydrogen bond acceptor basicity, polarizability and solvent electrophilicity, using linear multiple regression analysis shows that the reaction is influenced by these properties of the solvent. From the regression coefficients, information on the mode of solvation of the reactants and the transition state is obtained. The reaction has also been studied at different temperatures and the thermodynamic parameters Δ H#, Δ S# and Δ G# are evaluated. [ABSTRACT FROM AUTHOR]

2-Cyano-N-(tetrahydrocarbazole)acetamide (1) was utilized for the synthesis of several new arylazocarbazole derivatives (2a-e). Compound (1) reacted with phenyl isothiocyanate to yield the corresponding non-isolable intermediate (3), which gave, upon treatment with dilute hydrochloric acid, thiocarbamoyl derivative (4). Compound (3) reacted with chloroacetone, chloroacetic acid, chloroacetyl chloride, ethyl bromoacetate, and phenacyl bromide to afford thiazolone derivatives (6), (8), and (10), respectively. Compound (1) was heated in the presence of pyridine and/or hydrazine hydrate and/or isatine to give the corresponding tetrahydrocarbazole derivatives (13), (14), and (18), respectively. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. [ABSTRACT FROM AUTHOR]

3,4-Dihydro-1,4,4a,6a-tetraaza-benzo[a]fluoren-2-one, a new tetracyclic heterocyclic framework, is designed through a simple and convenient synthetic sequence. Its 6-aryl derivatives are synthesized starting from 1H-indole-2-carboxylic acid. The reaction of differently substituted phenacyl bromides with 1H-indole-2-carboxylic acid and POCl3-mediated cyclization of the resultant 1H-indole-2-carboxylic acid phenacyl ester provided 2-oxa-4a-aza-fluoren-1-one, and its sequential reaction with hydrazine and 2-chloro-acetamide furnished the desired new heterocyclic compounds 7a-f. [ABSTRACT FROM AUTHOR]

2-Aminothiazole and 2-iminothiazolidine derivatives were synthesized from the reaction of phenacyl bromide, thiourea, and its derivatives in aqueous media catalyzed by diammonium hydrogen phosphate (10%) and DABCO (10%) at room temperature in an efficient and simple procedure. [ABSTRACT FROM AUTHOR]

A series of 4-aryl-2-(3-methyl-7-substituted quinoxaline-2-one-1-yl)-1,3-thiazoles (6a-l) and 4-substituted alkyl-2-(3-methyl-7-substituted quinoxaline-2-one-1-yl)-1,3-thiazoles (8a-i) were synthesized in good yield by condensing 2-(3-methyl-7-substituted l,2-oxoquinoxalin-1(2H)-yl)ethanethioamides (5a-c) with substituted phenacyl bromide and dichloroacetone followed by treatment with secondary amines, respectively. The intermediates, 5a-c were conveniently obtained by reacting phosphorus pentasulphide with 2-(3-methyl-7-substituted-2-oxoquinoxalin-1(2H)-yl) acetamides (4a-c) which in turn were synthesized from ethyl (3-methyl-7-substituted-2-oxoquinoxalin-1(2H)-yl) acetates (3a-c) by aqueous ammonia treatment. The newly synthesized compounds were characterized by IR, 1H NMR, 13C NMR, and Mass spectral and elemental analyses. These compounds were screened for in vitro antibacterial activity against five pathogenic strains and antifungal activity against four fungi. Preliminary results revealed that some of the synthesized compounds showed promising antimicrobial activity. [ABSTRACT FROM AUTHOR]

An expeditious, solvent-free, and high yielding synthesis of nitrogen containing heterocycles from 1,2,4-s-triazole, benzoin, chloroacetic acid or phenacyl bromide under microwave irradiation is described. This improved greener synthetic methodology provides a simple and straightforward one-pot approach for the synthesis of a variety of heterocycles. [ABSTRACT FROM AUTHOR]

5-Benzylidene-2-thiohydantoin ( 1 ) and 5,5-dimethyl-2,4-dithiohydantoin ( 6 ) undergo Mannich reaction with formaldehyde and morpholine to give the corresponding Mannich products 2 and 7 , respectively. Subsequent reaction of the product 2 and 7 with phenacyl bromide gives the corresponding 2-benzolmethylthiohydantoin Reactionof 5-benzylidene-2-carbomethoxythiohydantoin ( 5b ) with P 2 S 5 afforded 4-benzylideneimidazo[2,1-b]-thiazole-2-thione-5-one ( 13 ) as the sole product. Reaction of 2-thio and 2,4-dithiohydantoin derivatives 2 and 7 with (2,3,4,6-tetra- O -acetyl-α-D-gluco- or galgctopyranosyl) bromide or (2,3,4-tri- O -acetyl-α-xylopyranosyl) bromide afforded the corresponding S-glucogalacto- or xylosides ( 14-19 ). Many attempts to deacetylation of the resulting S-nucleosides and to get N-nucleosides were tried. [ABSTRACT FROM AUTHOR]