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In this study, a highly effective microwave‐assisted method employing a multicomponent domino Knoevenagel/phospha‐Michael reaction has been established. This approach facilitates the synthesis of a novel set of pyrazolylphosphonate derivatives in good yields by combining aryl aldehydes with pyrazolones and trialkylphosphites, utilizing piperidine as a Bronsted base catalyst. All pyrazolylphosphonates have been characterized by means of IR, 1H‐NMR, 13C‐NMR, and HRMS analyses and physical methods. This protocol can be characterized by its eco‐friendly nature, exceptional efficiency in terms of product yields, and short reaction times. [ABSTRACT FROM AUTHOR]

A green and efficient protocol for a one‐pot condensation of 1‐(2,4‐dinitrophenyl)‐3‐(thiophen‐2‐yl)‐1H‐pyrazol‐5(4H)‐one (1) with aromatic and aliphatic aldehydes in different ratios to synthesize novel heterocyclic compounds containing pyrazolone and pyranopyrazole moieties. The reactions were conducted using the ultrasonic and traditional methods. The sonication ensured more efficiency in the rate and yield of the reactions. The structures of the synthesized compounds were elucidated by different spectroscopic methods. Additionally, an enantioselective synthesis of (R)‐ and (S)‐α‐alkylated acid was achieved using 1‐(2,4‐dinitrophenyl)‐4‐(hydroxymethyl)‐3‐(thiophen‐2‐yl)‐1H‐pyrazol‐5(4H)‐one (6) as chiral auxiliary, (S)‐4‐Methyl‐5‐nonanol the aggregation pheromone of red palm weevil was efficiently prepared and used for trapping the red palm weevil. [ABSTRACT FROM AUTHOR]

Tetrahydropyrimidinone derivative was synthesized through one‐pot three components condensation of 1,3‐diphenylpyrazole‐4‐carbaldehyde with pentan‐2,4‐dione and urea under Biginelli reaction conditions. The corresponding chloro‐ and hydrazino derivatives were synthesized and utilized for the construction of some valuable N‐heterocycles encompassing both pyrazole and pyrimidine cores, such as triazolopyrimidine, tetrazolopyrimidine, pyrazole, and pyrazolone derivatives through condensation with nitrogen nucleophiles and carbon electrophiles. The antiproliferative activity evaluation of the synthesized compounds against four human carcinoma cell lines namely, liver carcinoma (HepG2), breast adenocarcinoma (MCF7), prostate cancer (PC3), and colon cancer (HCT‐116) cell lines revealed that some of them provided significant potency, as well as the density‐functional theory (DFT) was studied. The permeability of various hydrophilic and hydrophobic synthesized compounds across both normal and cancer cells is confirmed via DFT simulation in which the much higher permeability through aquaporin channels revealed the selective cytotoxicity toward cancer cells. [ABSTRACT FROM AUTHOR]

Trifluoromethylated molecules, as well as pyrazol‐3‐one derivatives, are found in a wide range of biologically active compounds. An highly facile, green and mild access to substituted 3‐(trifluoromethyl)‐4,5‐dihydro‐1H‐furo[2,3‐c]pyrazole derivatives by the cascade [3 + 2] Michael/Alkylation of unsaturated pyrazolones with α‐bromomalonate has been developed. The reactions can be performed in a easily available and environmentally benign solvent, and the substituted 3‐(trifluoromethyl)‐4,5‐dihydro‐1H‐furo[2,3‐c]pyrazole derivatives can be obtained in good to excellent yields by a simple purification step. The antifungal activities of these functional pyrazole derivatives were also evaluated and they showed high antifungal activity against Alternaria solani. [ABSTRACT FROM AUTHOR]

Pyridine‐2(1H)‐thiones were prepared and reacted with several active halogenated reagents to afford novel thieno[2,3‐b]pyridines in excellent yields. Thieno[2,3‐b]pyridine‐2‐carbohydrazide derivative was prepared by the reaction of either ethyl 2‐((3‐cyanopyridin‐2‐yl)thio)acetate derivative or thieno[2,3‐b]pyridine‐2‐carboxylate derivative with hydrazine hydrate. On the other hand, the reaction of either pyridine‐2(1H)‐thione or ethyl 2‐((pyridin‐2‐yl)thio)acetate derivative with hydrazine hydrate afforded the corresponding 1H‐pyrazolo[3,4‐b]pyridine derivative. Thieno[2,3‐b]pyridine derivatives reacted with several reagents to afford the corresponding pyrimidine‐4(3H)‐ones and [1,2,3]triazin‐4‐(3H)‐one. Moreover, 2‐carbohydrazide derivative reacted with β‐dicarbonyl reagents to give 2‐((3‐methyl‐1H‐pyrazol‐1‐yl)carbonyl)thienopyridines. The structure of the target molecules is elucidated using elemental analyses and spectral data. [ABSTRACT FROM AUTHOR]

An efficient and novel method for the synthesis of pyrazolo[3,4‐f]quinoline derivatives by an efficient in situ reduction and cyclization reaction of 6‐nitro‐1H‐indazole, aromatic aldehydes, and 4‐hydroxy‐2H‐chromen‐2‐one or barbituric acid has been developed. Compared with amino compounds, nitro compounds are easier to obtain and more stable. The synthesis was achieved by using a multicomponent procedure under Fe/H2O medium. The advantages of this method are mild conditions, operational simplicity, high yields, and wide range of substrates. [ABSTRACT FROM AUTHOR]

Magnetic multiwalled carbon nanotube nanocomposite as a recoverable catalyst for the synthesis of novel 1,3‐thiazolidine‐4‐ones at room temperature in a one‐pot procedure without additional organic solvents. IR, 1HNMR, and 13CNMR spectroscopies and elemental analysis were used for the identification of these compounds. Moreover, the catalyst could be easily recovered by magnetic separation and recycled for five runs without significant loss of its catalytic activity. All of synthesized compounds were characterized by IR, NMR, and elemental analyses. [ABSTRACT FROM AUTHOR]

An efficient and green reactions of isatins, 3‐amine‐1H‐pyrazole (5‐methyl‐1H‐pyrazol‐3‐amine) and 1,3‐diketone in aqueous medium for the synthesis of novel 1′,7′,8′,9′‐tetrahydrospiro[indoline‐3,4′‐pyrazolo[3,4‐b]quinoline]‐2,5′(6′H)‐dione derivatives were reported in this research. The advantages of this reaction are simple operation, mild‐reaction conditions, wide scope substrate, high yields, and friendly environment. The products were confirmed by IR, 1H NMR, 13C NMR, and HRMS. [ABSTRACT FROM AUTHOR]

A novel imidazo[4′,5′:3,4]pyrazolo[5,1‐c][1,2,4]triazine‐4,8‐dione heterocyclic system was synthesized starting from available 4‐amino‐6‐tert‐butyl‐3‐methylthio‐1,2,4‐triazin‐5(4H)‐one in four steps with 28% overall yield. [ABSTRACT FROM AUTHOR]

3‐Amino‐2‐benzenesulfonyl‐1‐alkyl/aryl‐1H‐pyrazolo[1,2‐b]phthalazine‐5,10‐dione derivatives were synthesized by the one‐pot, three‐component condensation of phthalhydrazide, aldehydes, and (phenylsulfonyl)acetonitrile in EtOH using 2‐hydroxyethylammonium acetate as catalyst. The advantages of this method include environmental friendliness, easy work‐up, and excellent yields. The reduction of some products and photophysical properties were also investigated. [ABSTRACT FROM AUTHOR]

A new series of pyrazolotriazoles 7a-l, 11, and 15a-c derived from the reaction of 3-amino-4-(arylhydrazono)-4,5-dihydropyrazol-5-one 3a, b with various types of hydrazonoyl chlorides 4, 10, 12, and 13 was being synthesized in existence of triethylamine. The spectral data were assured the postulated structures for all compounds. All 7-arylazopyrazolo[5,1- c][1,2,4]triazole derivatives 7a-l, 11, and 15a-c have been evaluated for their antimicrobial and antitumor activities, and the results show that some derivatives have good to mild utility as antitumor and antibacterial operators. Moreover, the computational studies using AutoDock tools 4.2 are confirming the results in biological activity. [ABSTRACT FROM AUTHOR]

A highly efficient catalyst-free1,3-dipolar cycloaddition reaction of methyleneindolinones and C, N-cyclic azomethine imines was realized. The reactions afforded a large variety of spirooxindoles in high yields (up to 99%) and excellent diastereoselectivities (dr > 20:1). Furthermore, the configuration of one of the products was determined on the basis of X-ray structural analysis. Accordingly, a possible transition-state model was proposed. [ABSTRACT FROM AUTHOR]

New convenient one-pot method for reduction of hetarenediazonim tetrafluoroborates to the hetarylhydrazine derivatives was developed. Interaction of 8-carboxyethyl-3-( tert-butyl)-4-oxo-4,6-dihydropyrazolo[5,1- c][1,2,4]triazine-7-diazonium tetrafluoroborate with anhydrous SnCl2 in anhydrous CF3CO2H, and further sequence of one-pot operations led to formation of various derivatives of the unstable ethyl 3-( tert-butyl)-7-hydrazinyl-4-oxo-4,6-dihydropyrazolo[5,1- c][1,2,4]triazine-8-carboxylate (hydrochloride, hydrazides, hydrazones, and pyrazoles), which were isolated in high yields. The anhydrous conditions were first used with SnCl2 and allowed to exclude hydrolysis of the ester group and formation of the by-products. [ABSTRACT FROM AUTHOR]

A novel series of thiazolopyrimidines, thiazolopyrimidinones, imidazolothiazoles, and 1-thiazole-5-pyrazolone was synthesized under . Most of the synthesized compounds were screened in vitro antitumor, antioxidant, and antimicrobial activities. [ABSTRACT FROM AUTHOR]

Complementary strategies to 2,5-disubstituted pyrazolo[4,3- c]cinnolin-3-ones are reported herein, providing late stage substituent introduction at either the 2- or the 5-position. Treating a readily prepared 4-thiocinnoline ester with substituted hydrazines afforded late stage access to the 2-position, while late stage substituent introduction at the 5-position was achieved via two different strategies: of 4-hydrazonopyrazol-3-ones, followed by a ring-closing SNAr tactic and direct reaction of 5-(2-fluorophenyl)-2,4-dihydro-3 H-pyrazol-3-ones with aryl diazonium salts, followed by . The strategies described herein provide practical and general methods to prepare 2,5-disubstituted pyrazolo[4,3- c]cinnolin-3-ones. [ABSTRACT FROM AUTHOR]

3-Methyl-1-thiocarbamoyl-2-pyrazolin-5-one has been utilized as a core for the synthesis of some 1-(thiazol-2-yl)-pyrazolin-5-one derivatives through diazo-coupling reaction and/or followed by with some α-halogenated reagents such as bromoacetone, phenacyl bromide, and ethyl bromoacetate. Base prompted addition of the core compound to an equimolar amount of phenyl isothiocyanate furnished 3-methyl-4-phenylthiocarbamoyl-1-thiocarbamoyl-2-pyrazolin-5-one which undergoes with α-halogenated reagents at the more reactive phenylthiocarbamoyl moiety to afford the corresponding 4-(thiazol-2-yl)-1-thiocarbamoyl-2-pyrazolin-5-ones. The new synthesized thiazolyl-pyrazolone compounds were evaluated for their potential antioxidant activity by using (ABTS Radical Cation Decolorization Assay). [ABSTRACT FROM AUTHOR]

4-(Thiazol-2-yldiazenyl)-1 H-pyrazole-3,5-diamine ( 2) was prepared by the reaction of 2-thiazolylazomalononitrile ( 1) with hydrazine hydrate in boiling ethanol and used as key for the synthesis of polyfunctionally substituted pyrazolo[1,5- a]pyrimidines via its reactions with reagents having 1,3-dielectrophilic centers. Structures of the newly synthesized compounds were established by elemental analysis and spectral data. Representative compounds of the synthesized products were tested and evaluated as antioxidant agents. The results revealed that compounds ( 3), ( 4), ( 5), and ( 9) displayed promising antioxidant activity compared to the activity of ascorbic acid. [ABSTRACT FROM AUTHOR]

The synthesis of various heterocyclic compounds using acetoacetanilide[AAA], we have demonstrated that acetoactanilide are versatile for the synthesis of pyrazolopyrimidine derivatives. Thus, to explore further, we sought that the reaction of various acetoactanilide, an appropriate aldehyde and 5-amino- N-cyclohexyl-3-(methylthio)-1 H-pyrazole-4-carboxamide in the presence of base in isopropyl alcohol could be an effective strategy to furnish the novel pyrazolopyrimidine derivatives. Here we describe the novel synthetic methodology for the fused pyrazolopyrimidines. [ABSTRACT FROM AUTHOR]

A three-component reaction of isatin, 3-methyl-1-phenyl-1 H-pyrazol-5-amine, and piperidine-2,4-dione was treated in catalyzed by TsOH and provided an efficient and green method for the synthesis of spiro[indoline-3,4′-pyrazolo[3, 4- b][1,6]naphthyridine]-2,5′(1′ H)-dione derivatives in high yields. [ABSTRACT FROM AUTHOR]

A three-component reaction for the synthesis of new coumarin-fused tetracyclic system from 4-hydroxycoumarin, aldehydes, and 5-aminopyrazoles/5-aminoisoxazole is described. In the presence of , 4,7-dihydro-1H-pyrazolo[3,4- b]pyridines ( 4) and pyrazolo[3,4- b]pyridines ( 5) were obtained in acetonitrile and dimethylsulfoxide medium, respectively. The reaction gave rise to 4,5-dihydro-1H-pyrazolo[3,4- b]pyridin-6(7 H)-ones ( 6) in acetic acid-ethanol combination system, which involved the C-O . 4-Hydroxy-6-methyl-2H-pyran-2-one and acenaphthylene-1,2-dione were also examined, affording the corresponding C-O products. Mechanism indicates that the reaction is reversible in acetic acid-ethanol combination system. [ABSTRACT FROM AUTHOR]

The acid hydrazide derivatives 2 were converted into pyrazolone, triazinone, and schiff bases. However, the reaction of Schiff base 12 with malononitrile or thioglycolic acid gives the pyrazolotriazinone or thiazolidinone derivative, respectively. The structures of the newly synthesized compounds were established on the basis of IR, 1H-NMR, mass spectral data, and elemental analyses. The antimicrobial activities of the synthesized compounds were examined against two types of bacteria and two types of fungi. Some of the tested compounds showed promising activities. [ABSTRACT FROM AUTHOR]

Synthesis of pyrazolo[1,5- a]pyrimidines, [1,2,4]triazolo[1,5- a]pyrimidine, 8,10-dimethyl-2-(5-methyl-1-phenyl-4,5-dihydro-1 H-1,2,3-triazol-4-yl)pyrido[2′,3′:3,4]-pyrazolo[1,5- a]pyrimidine, benzo[4,5]imidazo[1,2- a]pyrimidine via heterocyclic amines, and sodium 3-hydroxy-1-(5-methyl-1-phenyl-1 H-1,2,3-triazole-4-yl)prop-2-en-1-one were carried out. Also, synthesis of isoxazoles, and pyrazoles from sodium 3-hydroxy-1-(5-methyl-1-phenyl-1 H-1,2,3-triazole-4-yl)prop-2-en-1-one and hydroxymoyl chlorides and hydrazonoyl halides, respectively, were made. Analogously, (1,2,3-triazol-4-yl)thieno[2,3- b]pyridine derivatives were obtained from sodium 3-hydroxy-1-(5-methyl-1-phenyl-1 H-1,2,3- triazole-4-yl)prop-2-en-1-one and cyanothioacetamide followed by its reacting with active methylene compounds. In addition to full characterization of all synthesized compounds, they were tested to evaluate their antimicrobial activities, and some compounds showed competitive activities to those of tetracycline, the typical antibacterial drug, and clotrimazole, the typical antifungal drug. [ABSTRACT FROM AUTHOR]

Series of new substituted pyrazolone derivatives via Betti's of pyrazolone and different aldehydes has been reported successfully under ambient reaction conditions. The structural elucidation of newly synthesized compounds was done using analytical and spectroscopic tools such as elemental analysis, 1H NMR, 13C NMR, and mass spectroscopy. Physicochemical parameters, toxicity profiles and drug likeness properties were studied using various bioinformaticals tools like Osiris and molinspiration. These results viz., the good correlations between the inhibitory activities and the computational values make the molecules available for future protein-ligand interaction studies. It further provided useful information in understanding the structural and chemical features of the drug in designing and finding new potential inhibitors. [ABSTRACT FROM AUTHOR]

Reaction of dicyandiamide with series of afforded guanidinyl pyrazolones 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, respectively. Although reaction of dicyandiamide with urea, acetamide, bezamide, allantion, p-aminobenzoic acid, sulphanilic acid, and adenine gave biguanides 20, 21, 22, 23, 24, 25, 26, respectively. All compounds have been characterized on the basis of IR and 1H-NMR. [ABSTRACT FROM AUTHOR]

Phenylene bis-pyrazolone derivatives were obtained by condensation of two aromatic β-diketo diesters with methyl-, 2-hydroxyethyl- and phenylhydrazines. The pyrazolone rings are connected to the central benzene ring by their C-3, leaving C-4 free for further . Thus, and despite their low solubility, these compounds were successfully nitrosated in good yield providing new chelating dioximes. [ABSTRACT FROM AUTHOR]

A series of some fused heterocycles originated from pyrazolopyrimidines were synthesized using 4-amino1-methyl-3-propyl-1 H-pyrazole-5-carboxamide as a starting material. The with different followed by and with different aryl boronic acids of 7-chloro-5-(4-chlorophenyl)-1-methyl-3-propyl-1 H-pyrazolo[4,3- d]pyrimidine were performed. Also, the oxidative of 1-(5-(4-chlorophenyl)-1-methyl-3-propyl-1 H-pyrazolo[4,3- d]pyrimidin-7-yl)hydrazine with different aldehydes in the presence of diacetoxy iodobenzene are described. All the synthesized compounds were characterized by analytical and spectroscopic methods. [ABSTRACT FROM AUTHOR]

5-Amino-4-formyl pyrazole carboxylate gave facile reactions with malononitrile, hydrazine, and ketones in the presence of piperidine furnished substituted pyrazolo[3,4- b]pyridines and pyrazolo[3,4- b]quinolones. The pyridazine sulfonamides were obtained by the reaction of 5-chloro 4-formyl pyrazole carboxylate with sulfonamide derivatives. [ABSTRACT FROM AUTHOR]

New series of (thieno[2,3- c]pyrazolo-5-yl)-[1,2,4]triazolo[3,4- b][1,3,4]thiadiazoles 10a, 10b, 10c and (thieno[2,3- c]pyrazol-5-yl)-1,3,4-oxadiazol-3(2H)-yl)ethanones 6a, 6b, 6c has been synthesized from thieno[2,3- c]pyrazole-5-carbohydrazide 3 by multistep reaction sequence. (5-Aryl-1,3,4-oxadiazol-2-yl)-1H-thieno[2,3- c]pyrazoles 4a, 4b, 4c were also synthesized from thieno[2,3- c]pyrazole-5-carbohydrazide 3 by with various . The hydrazide 3 was obtained by reaction of thieno[2,3- c]pyrazole-5-carboxylate 2 with hydrazine hydrate in good yield, and compound 2 was obtained by the reaction of 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde 1 and 2-ethyl thioglycolate in presence of sodium alcoholate in good yield. [ABSTRACT FROM AUTHOR]

The key 6-amino-3-methyl-4-aryl-1-(5′-substituted-3′-phenyl-1 H-indol-2′-carbonyl)-1,4-dihydropyrano[2,3- c]pyrazol-5-carbonitriles 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k, 3l, 3m, 3n, 3o were prepared by of 3-methyl-1-(5′-substituted-3′-phenyl-1 H-indol-2′-carbonyl)-5-(4 H)-pyrazolones 1a, 1b, 1c with arylidine derivatives of malononitrile 2a, 2b, 2c, 2d, 2e. The compounds 3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h, 3i, 3j, 3k, 3l, 3m, 3n, 3o were subjected to reaction with formamide, , and to afford the title compounds 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i, 4j, 4k, 4l, 4m, 4n, 4o, 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n, 5o, and 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n, 6o, respectively. The structures of all these previously unknown compounds were confirmed by their spectral studies and elemental analysis. These compounds were screened for their antimicrobial and antioxidant activities. [ABSTRACT FROM AUTHOR]

1,4-Diazabicyclo[2.2.2]octane has been explored as an efficient catalyst to effect the between malononitrile, 4-arylurazoles, and aromatic aldehydes in ethanol under ultrasound irradiation conditions. The reactions proceeded very rapidly under mild conditions to furnish the corresponding pyrazolo[1,2- a][1,2,4]triazole-1,3-dione derivatives in excellent yields. [ABSTRACT FROM AUTHOR]

A mild and efficient method for the synthesis of 10-aryl-6,7,8,10-tetrahydrocyclopenta[ b]pyrazolo[4,3- f]quinolin-9(3 H)-one derivatives is described in high yields at 50°C in . The method involves a three-component reaction of aromatic aldehyde 1 H-indazol-5-amine and cyclopentane-1,3-dione. [ABSTRACT FROM AUTHOR]

Diazotization of 3-methyl-4-phenyl-1 H-pyrazol-5-amine 1 in hydrochloric acid has been reported to afford the corresponding diazonium salt 2. The latter underwent azocoupling with a variety of active methylene compounds (barbituric 3a and thiobarbituric 3b acid, 2-hetarylpyrimidine-4,6-dione 6a 6b, 4-hydroxy-6-methylpyridin-2(1 H)-one 10a, 4-hydroxy-6-methyl-2 H-pyran-2-one 10b, 4-hydroxy-1- p-tolyl-1 H-pyrazole-3-carboxylic acid ethyl ester 14, 1,3-thiazolidine-2,4-dione 16a, 2-thioxo-1,3-thiazolidin-4-one 16b) to yield new pyrazolylazo derivatives. Fused pyrazolo[5,1- c][1,2,4]triazines 5, 9a 9b, 12, 13 were obtained by heterocyclization reactions. Copyright © 2013 HeteroCorporation [ABSTRACT FROM AUTHOR]

An efficient one-pot synthesis of spiro[indoline-3,1′-pyrazolo[1,2- b]phthalazine] derivatives via three-component reaction of phthalhydrazide, isatin, and malononitrile (cyanoacetic ester) is described. This new protocol has the advantages of high efficiency, mild reaction conditions, one-pot procedure, and convenient operation. [ABSTRACT FROM AUTHOR]

A series of novel 4-hetaryl substituted pyrazolo[1,5- a][1,3,5]triazines were synthesized by microwave assisted reaction between O,S-diethyl hetaroylimidothiocarbonates and 5-amino-3-aryl-1 H-pyrazoles under solvent-free conditions. This procedure led to the formation of mixtures of two new pyrazolotriazine derivatives in a 1:4 ratio, which were separated by column chromatography being their corresponding structures unambiguously established by spectroscopic and analytical techniques. Comparison of the reactions mediated by microwave irradiation and by conventional heating in solution of DMF showed that both procedures afforded the same mixtures of products, but the first approach required shorter reaction times and gave higher yields than the second one. [ABSTRACT FROM AUTHOR]

This study is in continuation of our work related to 5-pyrazolones aimed at synthesizing new heterocycles with dyeing and anticipated biological properties. Compounds 1 and 2; 1-methyl- or 1-(2,4-dimethylphenyl)-3-phenyl-1 H-pyrazol-5(4 H)-one, 3; 1-methyl-5-oxo-3-phenyl-4,5-dihydro-1 H-pyrazole-4-carbaldehyde and 4; 2-(1-methyl-5-oxo-3-phenyl-1 H-pyrazol-4(5 H)-ylidene)-3-phenylthiazolidin-5-one were prepared and subjected to diazotation with aromatic amines and diamines. New azo ( 1a- c, 2a, b, 3a, b, 4a, c) and bisazo dyes ( 2c, d, 4b) were obtained, and their structures were confirmed by spectroscopic and analytical methods. In addition, UV-vis measurements, dyeing performance, and fastness tests were carried out for all compounds. [ABSTRACT FROM AUTHOR]

The procedures for the synthesis of substituted pyrazolo[3,4- b]pyridine-6-ones and some of their properties are reviewed. [ABSTRACT FROM AUTHOR]

A series of 4-aryl-3,7,7-trimethyl-1-phenyl-7,8-dihydro-1 H-pyrazolo[3,4- b]quinolin- 5(6 H)-ones were synthesized by the three-component reaction of aromatic aldehydes, 3-methyl-1-phenyl-1 H-pyrazol-5-amine, and 5,5-dimethyl-1,3-cyclohexandione in the presence of sodium 1-dodecanesulfonate in aqueous medium. Compared to the previous methods, this new protocol has the advantages of convenient operation, higher yields, lower cost, and environmentally benign procedure. J. Heterocyclic Chem., (2012). [ABSTRACT FROM AUTHOR]

Novel pyrazolo[3,4- h][1,6]naphthyridine derivatives , , , , , and have been synthesized by Friedlander condensation of new 4-amino-3-methyl-1-phenyl-1 H-pyrazolo[3,4- b]pyridine-5-carbaldehyde ( o-aminoaldehyde) with active methylene ketones, such as symmetric acetone , monoalkylketones -, unsymmetrical dialkyl ketones -, p-bromophenylacetonitrile , β-ketoester , β-ketoamide , or diethyl malonate , respectively. J. Heterocyclic Chem., (2011). [ABSTRACT FROM AUTHOR]

A series of new indeno[1,2- b]pyrazolo[4,3- e]pyridin-5(1 H)-one derivatives were synthesized by three-component reactions of 1,3-indandione, 3-methyl-1 H-pyrazol-5-amine, and aldehyde in water under microwave irradiation without any catalyst. J. Heterocyclic Chem., (2010). [ABSTRACT FROM AUTHOR]

A novel series of pyrazolo [1,5-a] pyrimidines were synthesized by the condensation of substituted chalcones with 5-amino pyrazole in presence of dimethyl formamide. All the synthesized products were characterized by the spectral analysis. Further, all newly synthesized compounds were screened for their antimicrobial activity. Most of the compounds showed potent activity. J. Heterocyclic Chem., (2010). [ABSTRACT FROM AUTHOR]

A safe and efficient method was developed for the dibromination of pyrazolones and 5-hydroxypyrazoles by use of dibromoisocyanuric acid (DBI). The reaction gave the corresponding dibrominated pyrazolones in excellent yields (≥91%). J. Heterocyclic Chem., (2010). [ABSTRACT FROM AUTHOR]

A series of 1,3,6-trisubstituted and 1,3,5,6-tetrasubstituted pyrazolo [3,4-b] pyridines 5 have been synthesized by series of reactions on 1-phenyl-3-carboxylate pyrazolone to obtain o-aminoaldehyde, which undergo facile condensation with various α-methylene ketones, nitriles, and esters, furnish fused pyridine derivative in good yield. [ABSTRACT FROM AUTHOR]

Novel simple, efficient, and eco-friendly synthetic procedure for preparation of pyrazolo[3,4-b]quinolin-5-ones based on three-component microwaves-assisted heterocyclization reaction of 5-aminopyrazoles, aromatic aldehydes, and dimedone in hot-water medium was developed. The new method allows obtaining target heterocycles in good and excellent yields and with high degree of purity. J. Heterocyclic Chem., (2011). [ABSTRACT FROM AUTHOR]