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Hydrazine Hydrate (hydrazine + hydrate)
Selected AbstractsTin-Mediated Reduction of Azoarenes to Hydrazoarenes Using Hydrazine Hydrate.CHEMINFORM, Issue 48 2006B. Dinesh Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Chemoselective Reaction of Benz(g)indole Based Bisheterocycle Dicarboxylate Towards Hydrazine Hydrate: Synthesis and Antimicrobial Activity of New Triheterocycles-5-pyrrolylaminocarbonyl/mercaptooxadiazolyl/4-allyl-5-me rcaptotriazolylmethoxy-1-furfuryl-2-methylbenz(g)indoles.CHEMINFORM, Issue 45 2005Dundappa S. Donawade Abstract For Abstract see ChemInform Abstract in Full Text. [source] Hydrazine Hydrate Induced Reductive Cleavage of ,,,-Epoxy Ketones: An Efficient Procedure for the Preparation of ,-Hydroxy Ketones.CHEMINFORM, Issue 22 2005Jorge A. R. Salvador Abstract For Abstract see ChemInform Abstract in Full Text. [source] Ruthenium ,6 -Hexamethylbenzene Complexes Containing Dichalcogenoimidodiphosphinate LigandsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 6 2009Wai-Man Cheung Abstract Treatment of [Ru(,6 -C6Me6)Cl2]2 with AgOTf (OTf, = triflato) followed by K[N(R2PQ)2] gave the 16-electron complexes [Ru(,6 -C6Me6){,2 -N(R2PQ)2}][OTf] [Q = S, R = Ph (1) or iPr (2); Q = Se, R = Ph (3) or iPr (4)] which were isolated as air-stable blue or dark green crystals. For complex 1, when the crude product was recrystallised from CH2Cl2/hexane in air, orange crystals of [Ru(,6 -C6Me6){,3 -N(Ph2PS)2}][OTf] (1a) were isolated as a minor product. The reaction of compound 1 with ammonia, hydrazine hydrate and 4,4,-bipyridyl(4,4,-bpy) gave the 18-electron adducts [Ru(,6 -C6Me6){,2 -N(Ph2PS)2}L][OTf] [L = NH3 (5), N2H4 (6)] and dinuclear[{Ru(,6 -C6Me6)[,2 -N(Ph2PS)2]}2(,-4,4,-bpy)][OTf]2 (7), respectively. Treatment of compound 2 with Li[BEt3H] and NaBH4 afforded the ethyl [Ru(,6 -C6Me6){N(iPr2PS)2}Et] (8) andhydride [Ru(,6 -C6Me6){,2 -N(iPr2PS)2}H] (9) compounds, respectively. Formal potentials for Ru[N(R2PQ)2] complexes have been determined. The structures for complexes 1, 1a, 5, 6, 8 and 9 have been established by X-ray crystallography. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Synthesis of Pyrazoles by Treatment of 3-Benzylchromones, 3-Benzylflavones and Their 4-Thio Analogues with Hydrazine,EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 12 2006Albert Lévai Abstract The synthesis of pyrazoles 13,24 has been accomplished by treatment of 3-benzylchromones 1,5, 3-benzylflavones 6,12 and their 4-thio analogues 25,29 with hydrazine hydrate in hot pyridine. A plausible reaction mechanism for the formation of pyrazoles 13,24 is discussed. A 1H NMR study in [D6]DMSO allowed the presence of both pyrazole annular tautomers to be observed, due to the presence of intramolecular hydrogen bonds in each tautomer (OH--N and NH--O). GIAO/B3LYP/6-311++G** calculations were carried out on some model pyrazoles to provide a theoretical basis for the NMR experimental observations.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Synthesis of Pyrazolyl-2-pyrazolines by Treatment of 3-(3-Aryl-3-oxopropenyl)chromen-4-ones with Hydrazine and Their Oxidation to Bis(pyrazoles)EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 22 2004Albert Lévai Abstract The synthesis of several 1-acetyl-3-aryl-5-[3-(2-hydroxyphenyl)pyrazol-4-yl]-2-pyrazolines 3a,3h has been accomplished by treatment of the 3-(3-aryl-3-oxopropenyl)chromen-4-ones 1a,h with hydrazine hydrate in hot acetic acid. The 1-acetyl-3-aryl-5-(3-chromonyl)-2-pyrazolines 2a,2f were also obtained as by-products. Oxidation of the 1-acetyl-4-pyrazolyl-2-pyrazolines 3a,3f with DDQ gave the 3(5)-aryl-5(3)-[3-(2-hydroxyphenyl)pyrazol-4-yl]pyrazoles 5a,5f. The oxidation of the 2-pyrazoline rings was accompanied by N -deacylation. The reaction mechanisms of both transformations are discussed, the first one being supported by experimental results. The structures of all new derivatives were established by NMR and the evidence of prototropic tautomerism is carefully discussed. Theoretical calculations of energies and of the 1H and 13C NMR chemical shifts of the possible tautomeric forms of 5(3)-[3-(2-hydroxyphenyl)pyrazol-4-yl]-3(5)-(4-methoxyphenyl)pyrazole (5c), by B3LYP and GIAO, showed that compounds of this type probably exist as mixtures of two tautomers. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] 3(5)-(2-Hydroxyphenyl)-5(3)-styrylpyrazoles: Synthesis and Diels,Alder TransformationsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 21 2004Vera L. M. Silva Abstract Reactions between cinnamoyl(2-hydroxybenzoyl)methanes and hydrazine hydrate in acetic acid gave 3-(2-hydroxyphenyl)-5-styrylpyrazoles, while the corresponding reactions with phenylhydrazine yielded 5-(2-hydroxyphenyl)-1-phenyl-3-styrylpyrazoles as the major products and 3-(2-hydroxyphenyl)-1-phenyl-5-styrylpyrazoles as by-products. The reaction mechanism of this transformation is discussed. The first cycloaddition reactions between ortho -benzoquinodimethane and either 3-(2-hydroxyphenyl)-5-styrylpyrazoles or 5-(2-hydroxyphenyl)-1-phenyl-3-styrylpyrazoles afforded 5-[2-(3-aryl-1,2,3,4-tetrahydronaphthyl)]-3-(2-hydroxyphenyl)pyrazoles or 3-[2-(3-aryl-1,2,3,4-tetrahydronaphthyl)]-1-phenyl-5-(2-hydroxyphenyl)pyrazoles, respectively. These cycloadducts were converted into the corresponding naphthylpyrazoles by oxidation with DDQ in dry 1,4-dioxane. The structures of all new derivatives have been established by NMR spectroscopy. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] An efficient one-pot procedure for the preparation of 1,3,4-thiadiazoles in ionic liquid [bmim]BF4 as dual solvent and catalystHETEROATOM CHEMISTRY, Issue 3 2008Shahnaz Rostamizadeh The one-pot three component condensation of hydrazine hydrate with substituted phenylisothiocyanates followed by the addition of substituted benzaldehydes in the presence of ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF4) and in the absence of any other catalyst under mild condition afforded 1,3,4-thiadiazoles in excellent yields. The reaction workup is simple, and the ionic liquid was easily recovered from the reaction and reused. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:320,324, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20432 [source] Benzofuranyl-pyran-2-ones, -pyridazines, and -pyridones from naturally occurring furochromones (visnagin and khellin)HETEROATOM CHEMISTRY, Issue 1 2004Eman M. Keshk The novel and versatile enaminones 2a,b were synthesized by treatment of visnaginone methyl ether 1a or khellinone methyl ether 1b with N,N -dimethylformamide dimethylacetal. They were reacted with hippuric acid or N -acetylglycine to yield benzofuran-5-yl-2H-pyran-2-ones 3a,d. The reaction of 2a,b with cyanoacetamide and malononitrile dimer in sodium ethoxide gave benzofuran-5-yl-pyridones 4a,b and [benzofuran-5-yl-1H-pyridine-2-ylidene] malononitrile 5a, respectively. Refluxing 2a,b with hydrazine hydrate or with hydroxyla- mine afforded benzofuran-5-yl-1H-pyrazoles 6a,b and benzofuran-5-yl-isoxazoles 7a,b, respectively. Moreover, 2a,b coupled with aryl diazonium salt in the presence of sodium hydroxide to yield 3-(benzofuran-5-yl)-2-aryl-hydrazono-3-oxo-propanals 8a,b which were excellent precursors for the synthesis of pyridazines 9,12. © 2003 Wiley Periodicals, Inc. 15:85,91, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10219 [source] An Environmentally Benign, Highly Efficient Catalytic Reduction of p -Nitrophenol using a Nano-Sized Nickel Catalyst Supported on Silica-AluminaADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 7 2010Islam Hamdy Abd El Maksod Abstract A green and effective method is reported for the reduction of p -nitrophenol to p -aminophenol using a nano-sized nickel catalyst supported on silica-alumina in the presence of hydrazine hydrate as an alternative source of hydrogen. It was found that nickel loaded on a silica-alumina support is a very effective catalyst in the hydrogenation of p -nitrophenol to p -aminophenol. Thus it attained 100% conversion in only 69 seconds instead of 260 seconds for commercial Raney nickel. In addition, the possibility to reuse it more than one time with great efficiency gives it another advantage over commercial Rainey nickel which cannot be used more than once. This economical and environmentally friendly method provides a potentially new approach for the synthesis of the intermediate product of paracetamol in industry, which overcomes the drawbacks of the known reduction methods. The prepared catalysts were fully characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and electron spin resonance (ESR) tehniques. [source] Metal-Organic Frameworks (MOFs) as Heterogeneous Catalysts for the Chemoselective Reduction of Carbon-Carbon Multiple Bonds with HydrazineADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14-15 2009Amarajothi Dhakshinamoorthy Abstract The as-synthesized metal-organic frameworks (MOFs), particularly that based on aluminium coordinated with benzenedicarboxylic acid, constitute selective catalysts for the reduction of carbon-carbon multiple bonds in alkenes, alkynes and ,,,-unsaturated esters with hydrazine hydrate in acetonitrile under mild conditions. The present protocol enjoys advantages such as convenient reaction conditions and benign, reusable and cost effective catalyst. [source] Layered Double Hydroxide Supported Nanoplatinum and Nanopalladium Catalyzed Allylation of Aldehydes: A Mechanistic StudyADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 15 2005M. Choudary Abstract Layered double hydroxide (LDH)-supported nanoplatinum(0) and nanopalladium(0) catalysts were prepared by a simple ion exchange technique and subsequent reduction with hydrazine hydrate and used for the allylation of aldehydes to give moderate to good yields of homoallylic alcohols. Detailed mechanistic studies of LDH-Pd(0)-catalyzed allylation using XPS and TGA-MS reveal that a monoallyl-palladium complex is the key intermediate for the catalytic cycle. [source] Synergism of microwave irradiation and enzyme catalysis in synthesis of isoniazidJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 11 2007Ganapati D Yadav Abstract Isoniazid is a useful antitubercular drug widely employed in combination therapy with rifampicin. The synthesis of isoniazid from ethyl isonicotinate and hydrazine hydrate was studied in non-aqueous media via lipase-catalyzed hydrazinolysis under both conventional heating and microwave irradiation by using different supported lipases. Among three different commercial lipases used, namely Novozym 435 (Candida antarctica lipase), Lipozyme RM IM (Rhizomucor miehei lipase) and Lipozyme TL IM (Thermomyces lanuginosus lipase), Novozym 435 was found to be the most effective, with conversion of 54% for equimolar concentrations at 50 °C in 4 h. The rate of reaction as well as final conversion increased synergistically under microwave irradiation in comparison with conventional heating, which showed 36.4% conversion, even after 24 h, for the control experiment. Effects of various process parameters such as speed of agitation, catalyst loading, substrate concentration, product concentration and temperature were studied. A kinetic model is also described. Copyright © 2007 Society of Chemical Industry [source] Wet chemical synthesis of low bulk density aluminium hydroxide powderJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 5 2003JK Pradhan Abstract Fine, low bulk density aluminium hydroxide powdered gel was prepared by the mild base hydrolysis of an aqueous solution of aluminium sulfate with hydrazine hydrate. Parameters such as method of addition of reactant, initial concentration of Al3+, mole ratio, final pH and hydrolysis temperature have a profound effect on the lightness and particle size of the powder. Optimized conditions showed that the final pH, Al3+ concentration and method of addition of reactant have a major contribution on the formation of lighter grade powder. Experiments conducted using other bases also produced lighter particles under similar conditions. Deviation from the optimized conditions led to formation of a higher bulk density product. Copyright © 2003 Society of Chemical Industry [source] Microwave-assisted synthesis of quinolone derivatives and related compoundsJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2010Suhas Pednekar The Gould-Jacob type of reaction for the synthesis of ethyl 5-ethyl-8-oxo-5,8-dihydro-[1,3]-dioxolo[4,5-g]quinoline-7-carboxylate 4 has been carried out conventionally by the condensation between N -ethyl-3,4-methylenedioxyaniline 1 and diethyl ethoxymethylenemalonate 2 gave the unsaturated ester 3 and thermal cyclization in refluxing diphenyl oxide gave quinolone ethyl ester 4 and the results obtained were compared with single step microwave irradiation under solvent free conditions for the synthesis of 4. The esters on basic hydrolysis formed free acid 5, which, upon treatment with thionyl chloride gave the acid chloride 6. Treatment of acid chloride with o -phenylenediamine, hydrazine hydrate, ammonia, urea, and thiourea gave the amides (7,11). CS2 treatment in presence of KOH on 8 gave 12. We prepared 7,12 derivatives by conventional as well as microwave irradiation. These compounds have been characterized on the basis of IR, 1H NMR, MS, and elemental analysis. All the compounds prepared herein were screened for their antibacterial activity. Compounds 4, 5 possess promising antibacterial activity and compound 8 showed significant antibacterial activity. J. Heterocyclic Chem., (2010). [source] Ethyl-3,4-diaroyl-2-cyanobutyrate: A Synthon for novel heterocyclesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2009Adivireddy Padmaja A new class of aminopyrazolones, aminoisoxazolones, aminopyrimidinones, and thioxopyrimidinones were synthesized from Michael adduct, ethyl-3,4-diaroyl-2-cyanobutyrate, on reaction with different nucleophiles, hydrazine hydrate, hydroxylamine hydrochloride, and urea derivatives. J. Heterocyclic Chem., (2009). [source] 2H -Pyran-2-one-3-carbothioamide derivatives: Synthesis and reaction with hydrazine hydrateJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 1 2009Malika Makhloufi-Chebli N -Aryl-4-hydroxy-6-methyl-2H -pyran-2-one-3-carbothiamides and N -aryl-4-hydroxycoumarin-3-carbothiamides were synthesized by the reaction of arylisothiocyanates with 4-hydroxy-6-methylpyran-2-one and 4-hydroxycoumarin, respectively. Novel products 3-[bis(arylamino)methylene]-6-methyl-2H,4H -pyran-2,4-diones and N,N,-diaryl-4-hydroxycoumarin-3-carboximidamides have also been obtained in the same reactions. Novel 4-acetoacetyl-3-phenylamino-4,5-dihydro-5H -pyrazol-5-ones were synthesized from the reaction of N -aryl-4-hydroxy-6-methyl-2H -pyran-2-one-3-carbothiamides with an excess of hydrazine. The structure of all compounds was established by NMR and mass spectra. J. Heterocyclic Chem., (2009). [source] Synthesis of novel pyrazolo[3,4- d]pyridazine, pyrido[1,2- a]benzimidazole, pyrimido[1,2- a]benzimidazole and triazolo[4,3- a]pyrimidine derivativesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2008Mohamed R. Shaaban 4-Acetyl-5-methyl-1-phenyl-1H -pyrazole reacts with dimethylformamide dimethylacetal (DMF-DMA) to afford the corresponding (E)1-(5-methyl-1-phenyl-1H -pyrazol-4-yl)-3-(N,N -dimethylamino)-2-propen-1-one. The latter product undergoes regioselective 1,3-dipolar cycloaddition with nitrilimines and nitrile oxides to afford the novel 3-aroyl-4-(5-methyl-1-phenyl-1H -pyrazol-4-yl)carbonyl-1-phenylpyrazole and 3-aroyl-4-(5-methyl-1-phenyl-1H -pyrazol-4-yl)carbonyl isoxazole derivatives, respectively. It reacts also with 1H -benzimidazole-2-acetonitrile, 2-aminobenzimidazole and 3-amino-1,2,4-triazole to afford the novel pyrido[1,2- a]benzimidazole, pyrimido[1,2- a]benzimidazole and the triazolo[4,3- a]pyrimidine derivatives, respectively. The reaction of 3-aroyl-4-(5-methyl-1-phenyl-1H -pyrazol-4-yl) carbonyl-1-phenylpyrazole derivatives with hydrazine hydrate led to a new pyrazolo[3,4- d]pyridazine derivatives. [source] ,-Oxoanilides in heterocyclic synthesis: An expeditious synthesis of new polyfunctionally substituted pyridine and pyrazole derivativesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2008A. M. Hussein 3-Oxo- N -{4-[(pyrimidin-2-ylamino)sulfonyl]phenyl}butanamide 3 was condensed with (DMF-DMA) in refluxing dry dioxane to yield branched structure 4 not its linear isomeric 5. Compound 4 readily reacted with active methylene to yield compounds 8a-c, 14, 17 and 20 respectively. Also enaminone 4 reacted with phenyl hydrazine giving 24 and 25. In contrast, when compound 4 reacted with hydrazine hydrate in the same experimental conditions pyrazole derivative 27 was obtained. Furthermore, condensation of anilide 3 with triethylorthoformate in refluxing acetic anhydride afforded the ethoxy methylene derivative 28. On the other hand, compound 28 was reacted with active methylene reagents, and hydrazines to afford the products identical in all respects (mp., mixed mp., and spectral data) with those corresponding to compounds 6-27 respectively. Similarly, compound 3 was reacted with hydrazine hydrate to afford the reaction product 29. Also, compound 3 reacted with cyanoacetamide in refluxing ethanolic pipridine solution to yield the pyridine derivative 30. Finally, 3 reacted with hydroxylamine hydrochloride in refluxing ethanol/sodium acetate solution to yield the acyclic oxime derivative 31. [source] Regioselective synthesis of some novel pyrazoles, isoxazoles, pyrazolo[3,4- d]pyridazines and isoxazolo[3,4- d]pyridazines pendant to benzimidazoleJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 1 2007Mohamed R. Shaaban 2-Acetyl-1-methyl-1H -benzimidazole reacts with dimethylformamide-dimethyl-acetal (DMF-DMA) to afford the corresponding E -1-(1-methyl-1H -benzimidazol-2-yl)-3- N,N -dimethylaminoprop-2-enone. The latter compound reacts regioselectively with some nitrilimines and nitrile oxides to afford the corresponding pyrazole and isoxazole derivatives, respectively. These reaction products react with hydrazine hydrate to give the novel pyrazolo[3,4- d]pyridazine and isoxazolo[3,4- d]pyridazine derivatives, respectively. [source] Heterocyclic compounds from 4h -3,1-benzoxazin-4-one derivatives as anticancer agentJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 7 2005Taha M Abdel-Rahman Behaviour of 2-(4-oxo-4H -benzo[d][l,3]oxazin-2-yl)-benzoic acid (1) towards nitrogen nucleophiles namely, hydrazine hydrate, in different solvents, ammonium acetate, and o -phenylenediamine has been investigated to give aminoquinazolin-4-one, benzotriazepinone, spiro-type compound, and nitrogen bridgehead compounds 3-5, respectively. Also, reactivity of the aminoquinazolin-4-one 2 towards carbon elec-trophiles such as ethyl acetoacetate, ethyl phenylacetate, ethyl chloroacetate, and aromatic aldehydes has been discussed. Reaction of Schiff s base 8 with sulfur nucleophiles namely o -aminothiophenol and/or thio-glycolic acid afforded Michael type adducts. Structural assignments, of products 1-24 have been confirmed by elemental analysis and spectral data (1H- and 13C -NMR and MS fragmentation). The bioassay indicates that some of the target compounds obtained have good selective anticancer activity. [source] Synthesis of functionalized compounds containing pyridazine and related moietiesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 3 2005Jurij Svete 3-Aminopyridazines 17 and 3-hydrazinopyridazines 18 were used as building blocks for the preparation of various types of functionalized, pyridazine ring containing compounds. 3-Aminopyridazines were employed in the synthesis of 3-(6-chloroimidazo[1,2- b]pyridazin-2-yl)alanines 26, 27 and for the preparation of 3-amino-4H -pyrimido[1,2- b]pyridazin-4-ones 103, intermediates in the ,ring switching' synthesis of alkyl 1-pyridazin-3-yl-1,2,3-triazole-4-carboxylates 106. On the other hand, hydrazinopyridazines 18 were employed in a two-step preparation of 3-functionalized 1,2,4-triazolo[4,3- b]pyridazines via condensation with functionalized aldehydes and their enamino analogs followed by oxidative cyclization of the intermediate hydrazones. In this manner, 1,2,4-triazolo[4,3- b]pyridazin-3-yl substituted alanines 29, 30, polyols 33, 39,48, C -nucleosides 49, 50, and terpenes 58, 62, 64,69 were prepared. In another general approach, 3-hydrazinopyridazines 18 were treated with functionalized enaminones as 1,3-dielectrophiles to give the 1-(substituted pyridazin-3-yl)-1H -pyrazole derivatives containing an ester 72, 73, 75, 76, alanine 79, 84, 85, 87, 2-phenylethylamine 97, 99, and ,-amino alcohol functional element 98, 100. In the reaction of 4-oxohomoglutamate 82 with hydrazine hydrate and methyl hydrazine, chiral functionalized tetrahydropyridazinones 88a,b were obtained. [source] Spiro-heterocycles from substituted pyridines, pyrans and thiopyransJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2004Venkatapuram Padmavathi A new class of spiro-pyrimidines, pyrazoles and isoxazoles are prepared by nucleophilic reaction of 3,5-diaroyl-2,6-diaryl-piperidine-4,4-dicarbonitrile (1), 3,5-diaroyl-2,6-diaryl-tetrahydropyran-4,4-dicarbonitrile (2) and 3,5-diaroyl-2,6-diaryl-tetrahydrothiopyran-4,4-dicarbonitrile (3) with urea, N,N'-dimethyl urea, thiourea, hydrazine hydrate and hydroxylamine hydrochloride. [source] Synthesis and reactions of 3-amino-2-methyl-3H -[1,2,4]triazolo[5,1- b]-quinazolin-9-one and 2-hydrazino-3-phenylamino-3H -quinazolin-4-oneJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2003Mohamed A. Saleh The reaction of 3- N -(2-mercapto-4-oxo-4H -quinazolin-3-yl)acetamide (1) with hydrazine hydrate yielded 3-amino-2-methyl-3H -[1,2,4]triazolo[5,1- b]quinazolin-9-one (2). The reaction of 2 with o -chlorobenzaldehyde and 2-hydroxy-naphthaldehyde gave the corresponding 3-arylidene amino derivatives 3 and 4, respectively. Condensation of 2 with 1-nitroso-2-naphthol afforded the corresponding 3-(2-hydroxy-naphthalen-1-yl-diazenyl)-2-methyl-3H -[1,2,4]triazolo[5,1- b]quinazolin-9-one (5), which on subsequent reduction by SnCl2 and HCl gave the hydrazino derivative 6. Reaction of 2 with phenyl isothiocyanate in refluxing ethanol yielded thiourea derivative 7. Ring closure of 7 subsequently cyclized on refluxing with phencyl bromide, oxalyl dichloride and chloroacetic acid afforded the corresponding thiazolidine derivatives 8, 9 and 10, respectively. Reaction of 2-mercapto-3-phenylamino-3H -quinazolin-4-one (11) with hydrazine hydrate afforded 2-hydrazino-3-phenylamino-3H -quinazolin-4-one (12). The reactivity 12 towards carbon disulphide, acetyl acetone and ethyl acetoacetate gave 13, 14 and 15, respectively. Condensation of 12 with isatin afforded 2-[N -(2-oxo-1,2-dihydroindol-3-ylidene)hydrazino]-3-phenylamino-3H -quinazolin-4-one (16). 2-(4-Oxo-3-phenylamino-3,4-dihydroquinazolin-2-ylamino)isoindole-1,3-dione (17) was synthesized by the reaction of 12 with phthalic anhydride. All isolated products were confirmed by their ir, 1H nmr, 13C nmr and mass spectra. [source] Studies on the reactions of cyclic oxalyl compounds with hydrazines or hydrazones : Synthesis and reactions of 4-benzoyl-1-(3-nitrophenyl)-5-phenyl-1H -pyrazole-3-carboxylic acidJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2002Ahmet, ener The 1H -pyrazole-3-carboxylic acid 2, obtained from the furan-2,3-dione 1 and N -Benzylidene- N'-(3-nitrophenyl) hydrazine, was converted via reactions of its acid chloride 3 with various alcohols or N-nucleo-philes into the corresponding ester or amide derivatives 4 or 5, respectively. Nitrile 6 and anilino-pyrazole acid 7 derivatives of 2 were also obtained by dehydration of 5a in a mixture of SOCl2 with DMF and reduction of 2 with sodium polysulphide, respectively. While cyclocondensation reactions of 2 or 7 with phenyl hydrazine or hydrazine hydrate and 6 with only anhydrous hydrazine lead to derivatives of pyrazolo[3,4- d]-pyridazinone 8 and pyrazolo[3,4- d]pyridazine amine 9, respectivel. The reaction of 2 with 2-hydrazinopyri-dine provided hydrazono-pyrazole acid derivative 10, which was decarboxylated to give hydrazono-pyra-zole derivative 11. Pyrazolo[4,3- d]oxazinone 12 and 2-quinolyl pyrazolo[3,4- d]pyridazine 13 derivatives were also prepared by cyclocondensation reactions of 2 with hydroxylamine hydrochloride and 7 with acetaldehyde, respectively. [source] Synthesis of a deuterium-labelled standard of bufotenine (5-HO-DMT)JOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 14 2007Yu-Yun Wang Abstract The Batcho,Leimgruber strategy was employed to synthesize 3-(2-dimethylamino-[2H4]-ethyl)-1H -indol-5-ol (bufotenine, 5-HO-DMT) (8) from commercial 3-methyl-4-nitro-phenol (1), benzyl bromide and N,N,dimethylformamide,dimethylacetal. Compound 4 was synthesized from compound 3 using the Batcho,Leimgruber strategy in the presence of Raney nickel and hydrazine hydrate. Compound 4 was treated with oxalyl chloride, dimethylamine and lithium aluminum [2H4]-hydride to yield [2-(5-benzyloxy-1H -indol-3-yl)-[2H4]-ethyl]-dimethyl-amine (7). The benzyl ether in compound 7 was cleaved by hydrogenolysis to give bufotenine 8. Copyright © 2007 John Wiley & Sons, Ltd. [source] Synthesis of anion exchange polystyrene membranes for the electrolysis of sodium chlorideAICHE JOURNAL, Issue 4 2008Sonny Sachdeva Abstract We have prepared a cross-linked polystyrene anion exchange composite membrane for the electrolysis of sodium chloride to produce sodium hydroxide by selective removal of chloride ions. The composite membrane is homogeneously modified by gas phase nitration, followed by amination using hydrazine hydrate, and further reaction with dichloroethane and triethylamine to introduce quaternary ammonium charges on it. We showed that the membrane is specific to the transport of chloride ions through its pores. The performance of the membrane has been evaluated in terms of current efficiency and power consumption, and the effect of various parameters like current density, initial salt concentration, and circulation rate is studied. The maximum current efficiency obtained is 96.5% and the corresponding power consumption is 0.1216 kWh/mol at 5.2 N initial salt concentration and current density of 254 A/m2. © 2008 American Institute of Chemical Engineers AIChE J, 2008 [source] Production of monodisperse silver colloids by reduction with hydrazine: the effect of chloride and aggregation on SER(R)S signal intensity,JOURNAL OF RAMAN SPECTROSCOPY, Issue 2 2004U. Nickel Abstract SER(R)S spectra with high signal intensity of Nile Blue A sulfate and 1,1,-diethyl-2,2,-cyanine iodide present in low concentration (,0.05 µM) can be recorded by employing certain silver sols in the absence of any chloride and without highly aggregated particles. The sols have been prepared by reduction of silver nitrate with hydrazine hydrate in a special procedure at a carefully established pH. In the presence of chloride, the maximum SER(R)S signal observed for a ca. 0.5 µM solution of Nile Blue A is of similar magnitude employing either a silver sol according to Lee and Meisel or our sol C, which contains nearly exclusively single silver particles with diameters of about 50 nm. Without added chloride, however, only our sol produces SER(R)S spectra with similar intensity as with chloride. Because the influence of chloride and coagulation on the intensity of the SER(R)S-signal can be controlled by varying the additives to our silver sol, further experiments of this kind can help to elucidate how these two parameters influence the magnitude of the SERS enhancement. Copyright © 2004 John Wiley & Sons, Ltd. [source] Di- tert -butyl ketone hydrazone and di- tert -butyl ketone triphenylphosphoranylidenehydrazoneACTA CRYSTALLOGRAPHICA SECTION C, Issue 4 2006Claude Villiers Reaction of di- tert -butyl ketone with hydrazine hydrate gives di- tert -butyl ketone hydrazone, C9H20N2, which is dimerized by double hydrogen bonding in the solid state. Further reaction of this compound with dibromotriphenylphosphorane gives di- tert -butyl ketone triphenylphosphoranylidenehydrazone, C27H33N2P, in the structure of which double chains parallel to the c axis are formed through weak C,H,, and ,,, stacking interactions. The hydrazone group is nearly planar in both cases. In the second compound, one of the aromatic rings is nearly coplanar with the hydrazone moiety, indicating possible ,-conjugation. [source] Immunomodulatory and Anticancer Activities of Some Novel 2-Substituted-6-bromo-3-methylthiazolo[3,2- a]benzimidazole DerivativesARCHIV DER PHARMAZIE, Issue 4 2009Hatem A. Abdel-Aziz Abstract Ethyl 6-bromo-3-methyl-1,3-thiazolo[3,2- a]benzimidazole-2-carboxylate 2 was prepared by the ambient temperature bromination of ethyl 3-methyl-1,3-thiazolo[3,2- a]benzimidazole-2-carboxylate 1. The acid hydrazide 4 was obtained by the reaction of ester 2 with hydrazine hydrate. Treatment of compound 4 with benzaldehyde or 2-thiophenaldehyde yielded the corresponding hydrazones 6a and 6b, respectively, while the reaction of acid hydrazide 4 with ethoxymethylene malononitrile (7a) or with ethyl ethoxymethylene cyanoacetate (7b) in refluxing ethanol afforded pyrazole derivatives 9a and 9b, respectively. Taken together, from the biological investigations compounds 9a and 9b were the most significant inhibitors of LPS-stimulated NO generation from Raw murine macrophage 264.7, and, as another result, compounds 2 and 4 had a weak radical scavenging activity against DPPH radicals. Moreover, 2, 4, and 9a had a concomitant strong cytotoxicity against both colon carcinoma cells (HCT-116) and hepatocellular carcinoma cells (Hep-G2) while 9b showed specific cytotoxicity only against colon carcinoma cells. [source] | |||||||||||||||||||||||||