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Search Results: 1 - 10 of 402031 matches for " Nada M. Abunada "
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Synthesis of some new Indeno[1,2-e]pyrazolo[5,1-c]-1,2,4-triazin-6-one and Indeno[2,1-c]pyridazine-4-carbonitrile Derivatives  [PDF]
Hamdi M. Hassaneen, Nada M. Abunada, Huwaida M. Hassaneen
Natural Science (NS) , 2010, DOI: 10.4236/ns.2010.212164
Abstract: Diazonium chlorides of 5-amino-3-methypyrazole 1a and 5-amino-4-phenylpyrazole 1b coupled with 1,3-indanedione 2 and led to the formation of acyclic hydrazone 3a and a cyclic product indenopyrazolotriazine 4b respectively. Cyclization of the hydrazone 3a by boiling in acetic acid afforded the corresponding 4a. The hydrazone 3a reacted with malononitrile in boiling ethanol in the presence of piperidine and gave indeno[2,1-c]pyridazine-4-carbonitrile derivatives 5a,b. Also, coupling of 6 with aryl diazonium chlorides gave the corresponding indenopyridazine derivatives 8a-e. Acetylation, benzoylation and hydrolysis of compound 8a afforded the corresponding substitution products 10-12, respectively. The structures of the newly synthesized compounds were established on the basis of chemical and spectral evidences.
Reaction of thiocarboxanilide derivatives of 2-phenylimino-3-phenyl-4-thiazolidinone and 1,3-diphenyl-2-thioxo-4-imidazolone with hydrazonoyl halides and active chloromethylene compounds  [PDF]
Hamdi M. Hassaneen, Omar A. Miqdad, Nada M. Abunada, Ahmad A. Fares
Natural Science (NS) , 2011, DOI: 10.4236/ns.2011.33026
Abstract: The potassium salts of thiocarboxanilide of 2- phenylimino-3-phenyl-4-thiazolidinone and 1,3- diphenyl-2-thioxo-4-imidazolone react with hydrazonoyl halides in N,N-dimethylformamide to afford the corresponding 1,3,4-thiadiazoline derivatives. 2-Phenylimino-3-phenyl-4-thiazolidinone reacts with active chloromethylene compounds in N,N-dimethylformamide to give the corresponding thiazolylidenethiazolidin-4-one derivatives. The new compounds were characterized using IR, 1H NMR, 13C NMR and mass spectra.
Synthesis and antimicrobial evaluation of some new pyrazole, pyrazoline and chromeno[3,4-c]pyrazole derivatives
Abunada, Nada M.;Hassaneen, Hamdi M.;Samaha, Ahmed S. M. Abu;Miqdad, Omar A.;
Journal of the Brazilian Chemical Society , 2009, DOI: 10.1590/S0103-50532009000500024
Abstract: some new pyrazole-5-carbonitrile derivatives 8, 9 and pyrazole-5-carboxamide 13 were synthesized by the cycloaddition reaction of nitrilimines 3, 4 to α-cyanocinnamonitriles 5a-f and α-cyanocinnamamide 12a, b respectively. on the other hand 3, 4 add to ethyl α-cyanocinnamate 14a-f to give ethyl 2-pyrazoline-5-carboxylate derivatives 15, 16. also, cycloaddition of 3, 4 to 3-cyanocoumarin 19a or 3-phenylsulphonylcoumarin 19b or 3-bromocoumarin 19c give chromeno[3,4-c]pyrazol-4(3h)-one derivatives 20. in the same direction, the cycloaddition of 3, 4 to 3-acetylcoumarin 22 and 3-benzoylcoumarin 23 gives the corresponding dihydrochromeno[3,4-] pyrazol-4(3h)-one 24 and 25 respectively. oxidation of 24 and 25 give 20. most of the prepared compounds showed good to moderate antibacterial and antifungal activities.
Synthesis of New Derivatives of Heterocyclic Compounds Containing Pyridine, Pyrimidine and Triazole Ortho-Fused to Isoquinoline Moiety
Hamdi M. Hassaneen,Nada M. Abunada,Huwaida M. E. Hassaneen,Omar A. Miqdad
International Journal of Chemistry , 2012, DOI: 10.5539/ijc.v4n3p86
Abstract: 4-Amino-9,10-dimethoxy-2-phenyl-6,7-dihydro-2(H)-pyrido[2,1-a]isoquinoline-1,3-dicarbonitrile derivatives 4a-c were obtained from the reaction of 6,7-dimethoxy-3,4-dihydroisoqinoline-1-acetonitrile 1 with arylidenemalononitrile 2a-c in boiling acetonitile in the presence of piperidine. The reaction of 4a-c with triethyl orthoformate in acetic anhydride at reflux give the ethoxymethyleneamino derivatives 5a-c. Compounds 5a-c were reacted with hydrazine hydrate and give the corresponding 4-amino-3-imino-2-aryl-3,4,8,9-tetrahydro-2(H)-pyrimido[5?,4?:5,6]pyrido[2,1-a]isoquinoline-1-carbonitrile derivatives 6a-c. Refluxing compound 6a in an excess of triethyl orthoformate give 7a. When compounds 6a-c were refluxed with acetic anhydride or benzoyl chloride in pyridine, they afford the corresponding 4-methyl and 4-phenyl derivatives 8a-c and 9a-c, respectively. Compound 6a was refluxed in diethyloxalate and give product 10. Also, the reaction of 6a with C-acylhydrazonoyl halides 13a,b in refluxing chloroform in the presence of triethylamine afford 14a,b. Correct elemental analyses and spectral data (IR, 1H NMR, 13C NMR and MS) confirm the structure of the synthesized compounds.
Synthesis and Biological Activity Evaluation of Some New Heterocyclic Spirocompounds with Imidazolinone and Pyrazoline Moieties
Omar Abdelhay Miqdad,Nada M. Abunada,Hamdi M. Hassaneen,Ahmed S. M. Abu Samaha
International Journal of Chemistry , 2011, DOI: 10.5539/ijc.v3n4p20
Abstract: The synthesis of antimicrobial activity spirocompounds was achieved via the reaction of hydrazonoyl halides 1 with exocyclic 4-arylidene-2-methylimidazolin-5-one 3 in benzene in the presence of triethylamine. Correct elemental analyses and spectral data (IR, 1H NMR, 13C NMR and MS) confirm the structure of the synthesized spirocompounds. All the synthesized compounds were evaluated in vitro for their antimicrobial activity against five gram-positive and two gram-negative bacteria using well diffusion method in Mueller-Hinton agar. Most of them exhibited significant antibacterial activity compared with selected standard drugs.
Synthesis and Biological Activity of Some New Pyrazoline and Pyrrolo[3,4-c]pyrazole-4,6-dione Derivatives: Reaction of Nitrilimines with Some Dipolarophiles
Nada M. Abunada,Hamdi M. Hassaneen,Nadia G. Kandile,Omar A. Miqdad
Molecules , 2008, DOI: 10.3390/molecules13041011
Abstract: Several 1,3-diaryl-5-(cyano-, aminocarbonyl- and ethoxycarbonyl-)-2-pyrazoline, pyrrolo[3,4-c]pyrazole-4,6-dione and 1,3,4,5-tetraaryl-2-pyrazoline derivativeswere prepared by the reaction of nitrilimine with different dipolarophilic reagents. The newcompounds were characterized using IR, 1H-NMR, 13C-NMR and mass spectra. Biologicalscreening of some compounds is reported.
Synthesis and Antimicrobial Activity of Some New Pyrazole, Fused Pyrazolo[3,4-d]-pyrimidine and Pyrazolo[4,3-e][1,2,4]- triazolo[1,5-c]pyrimidine Derivatives
Nada M. Abunada,Hamdi M. Hassaneen,Nadia G. Kandile,Omar A. Miqdad
Molecules , 2008, DOI: 10.3390/molecules13071501
Abstract: Hydrazonyl bromides 2a,b reacted with active methylene compounds (dibenzoylmethane, acetylacetone, ethyl acetoacetate, phenacyl cyanide, acetoacetanilide, ethyl cyanoacetate, cyanoacetamide and malononitrile) to afford the corresponding 1,3,4,5- tetrasubstituted pyrazole derivatives 5-12a,b. Reaction of 12a,b with formamide, formic acid and triethyl orthoformate give the pyrazolo[3,4-d]pyrimidine, pyrazolo[3,4- d]pyrimidin-4(3H)one and 5-ethoxymethylene-aminopyrazole-4-carbo-nitrile derivatives 13-15a,b, respectively. Compounds 15a,b reacted with benzhydrazide and hydrazine hydrate to afford pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidine and [4-iminopyrazolo- [3,4-d]pyrimidin-5-yl]amine derivatives 16a,b and 17a,b. Reactions of compounds 17a,b with triethyl orthoformate and carbon disulfide give the corresponding pyrazolo[4,3-e]- [1,2,4]triazolo[1,5-c]pyrimidine derivatives 18a,b and 19a,b, respectively.
Pure Baer injective modules
Nada M. Al Thani
International Journal of Mathematics and Mathematical Sciences , 1997, DOI: 10.1155/s0161171297000720
Abstract: In this paper we generalize the notion of pure injectivity of modules by introducing what we call a pure Baer injective module. Some properties and some characterization of such modules are established. We also introduce two notions closely related to pure Baer injectivity; namely, the notions of a ¢ ‘-pure Baer injective module and that of SSBI-ring. A ring R is an SSBI-ring if and only if every smisimple R-module is pure Baer injective. To investigate such algebraic structures we had to define what we call p-essential extension modules, pure relative complement submodules, left pure hereditary rings and some other related notions. The basic properties of these concepts and their interrelationships are explored, and are further related to the notions of pure split modules.
Energy Pricing in Developing Countries  [PDF]
Sara Nada, M. Hamed
Open Access Library Journal (OALib Journal) , 2014, DOI: 10.4236/oalib.1100869
Abstract: This paper investigates the electric energy tariff in the developing countries on the basis of per unit system analysis. The smallest actual value of a tariff in the sample of countries is considered as the base for the studied system and so, a comparison is done. A tariff map is proposed for the dynamic variation of tariffs in different countries where the map becomes as a texture image. This simplifies comments and conclusions for the tariff traveling within others. The sample of countries is extended to three continents in order to differentiate between different systems of energy tariffs. It contains four groups as: Arab countries in two divisions, Asian group and African countries where different investigations and directions may be applied with. Single-phase and three- phase electric loads have been inserted and analyzed. A normalized fluctuation factor is proposed as an indicator to determine the philosophy of tariff variation in each country relative to others. Both domestic and commercial tariffs are analyzed and a sample of industrial energy price is investigated for specified power demands. It is recommended to use normalized fluctuation factor and tariff map for the evaluation of economic support.
Economic Modeling for the Renewable Energy Support  [PDF]
Sara Nada, M. Hamed
Open Access Library Journal (OALib Journal) , 2015, DOI: 10.4236/oalib.1101360
Abstract: This paper presents a general economic modification for the present energy strategy. This modification is unidirectional economic concept depending on three principles. The paper explains shortly the basics of engineering connections between renewable energy stations and the traditional electric power networks, illustrating the technical rules while the economical base has been accounted with time consideration. Converting stations and rectification principles are priced, simply. Also, the cost comparison may be noted in order to find the best quick way for development. The proposed support depends on three axes as the technical (direct current distribution systems), financial banking, and industrial activity. This leads to a concentration in the manufactured equipments and devices to be capable for encourage the application of direct current operation. The tools and devices in the electric systems of cars may be the first key for the technical implementation as a stable actual market in the world so that the industrial axis would lead to the commercial use with a reduced price for each component due to the high growth in mass production. It is concluded that, the proposed philosophy can be introduced on the basis of government support through electric and industrial companies besides governmental banks. Also, encourage policy for private investment sectors in marketing and financial authorities may be needed where a simple economic model is illustrated. This is an economic differential solution since it accounts the price ratio for the aimed target.
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