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New Synthesis Of 1,4-Diarylpiperazine-2,5-Dione And 3,4,5-Trisubstitutedpyridine-2(1h)-One, Fathi Abu-Shanab
New Synthesis Of 1,4-Diarylpiperazine-2,5-Dione And 3,4,5-Trisubstitutedpyridine-2(1h)-One, Fathi Abu-Shanab
Al-Azhar Bulletin of Science
Treatment of N-aryl 2-chloroacetamides (2a-f) with sodium isopropoxide in isopropyl alcohol afforded 1,4-diarylppiperazine-2,5-dione (3a-f). Treatment of malononitrile dimer (9), ethyl cyanoacetate (11) and the arylidines of cyanothioacetamide (13) with DMFDMA afforded the corresponding enamines (10, 12 and 14) respectively. Reaction of 14 with either sodium ethoxide or sodium methoxide affords 5-cyano-4-ethoxy-6-oxo-1,6-dihydro-pyridine-3-carboxylic acid amide (15) and 5-cyano-4-methoxy-6-oxo-1,6-dihydro-pyridine-3-carboxylic acid amide (16) respectively.
Some Reactions Of 6,8-Dibromo-2-Propenyl-4h-3,1-Benzoxazin-4-One With Nitrogen Nucleophiles Under Microwave Irradiation, A. Abdalha, M. Abou El-Regal, M. El-Kassaby, A. Nazeer
Some Reactions Of 6,8-Dibromo-2-Propenyl-4h-3,1-Benzoxazin-4-One With Nitrogen Nucleophiles Under Microwave Irradiation, A. Abdalha, M. Abou El-Regal, M. El-Kassaby, A. Nazeer
Al-Azhar Bulletin of Science
The benzoxazinone derivative (1) was prepared upon the action of crotonoyl chloride on 3,5-dibromoanthranilic acid in pyridine. Microwave irradiation assisted the aminolysis of (1) with nitrogen nucleophiles as benzyl amine, hydrazine hydrate and formamide to give the amide derivatives (2a-c) respectively. Quinazolinone derivatives (3a-e) were produced upon the action of primary amines such as m-nitroaniline, p-toluidine, p-anisidine, benzyl amine and/or hydrazine hydrate respectively on the benzoxazinone derivative (1). An excess amount of p-anisidine, phenylhydrazine and/or p-toluidine afforded the amide and quinazolinone derivatives (4a & 5a), (4b & 5b) and/or (5c) respectively. The benzoxazinone derivative (1) was subjected to react with …
Heteroaromatization With Sulphonamido Phenyl Ethanone: Part (Iii)*. Synthesis, Reactions And Biological Activity Of Enaminone Conjugated With Dimethylaminosulfonyl Moiety, Mahmoud Abdel Aal, Ahmed El-Maghraby, Saber Hassan, Mahmoud Bashandy
Heteroaromatization With Sulphonamido Phenyl Ethanone: Part (Iii)*. Synthesis, Reactions And Biological Activity Of Enaminone Conjugated With Dimethylaminosulfonyl Moiety, Mahmoud Abdel Aal, Ahmed El-Maghraby, Saber Hassan, Mahmoud Bashandy
Al-Azhar Bulletin of Science
4-(3-Dimethylaminoacryloyl)-N,N-dimethylbenzenesulfonamide (2) was prepared and used as key intermediate in the synthesis of the title compounds, the structure of these compounds were elucidated on the bases of elemental analysis, IR, 1H-NMR and mass spectra. The Antimicrobial and Antifungal activities of the prepared compounds are also reported.
Effect Of Inorganic Acid Solutions On Electrochemical Behavior Of Tin Electrode, R. Abou Shahba, A. Ahmed, E. Attia, A. El-Shennawy
Effect Of Inorganic Acid Solutions On Electrochemical Behavior Of Tin Electrode, R. Abou Shahba, A. Ahmed, E. Attia, A. El-Shennawy
Al-Azhar Bulletin of Science
The electrochemical behavior of tin metal was studied in some inorganic acid solutions; HCl, HNO3, H2SO4 and H3PO4, using the open circuit potential measurements and the potentiodynamic polarization technique. In addition, the metallographic structure of tin electrode was examined before and after immersion in test solution by using scanning electron microscope (SEM). The identification of the elements presented in the surface of specimen after immersion in different solutions was performed using an energy dispersion X-ray analysis(EDAX). The obtained results demonstrated that the aqueous dilution of HCl, H2SO4 and H3PO4 retarded the corrosion of tin electrode, (hydroxyl ion plays a part …
A New Approach For Graft Copolymerization Of Jute, E. El-Alfy, N. Zamzam, M. Fikry, M. Yousef, A. Abou-Okeil
A New Approach For Graft Copolymerization Of Jute, E. El-Alfy, N. Zamzam, M. Fikry, M. Yousef, A. Abou-Okeil
Al-Azhar Bulletin of Science
The graft copolymerization of glycidyl methacrylate (GMA) on jute fibers at ambient conditions is the desired goal. Graft copolymerization of (GMA) on jute fibers was carried out using Ammonium Persulphate Acetone Sodium Bisulphite (APS/ASBS) initiating redox system. The grafting reaction was studied with respect to graft yield (GY), grafting efficiency (GE) and total conversion (TC). Factors such as pH value, liquor ratio (L: R), redox initiator concentration, addition sequence, reaction time, temperature and GMA concentration [M], were investigated. The results obtained showed that the optimal grafting yield is obtained at the following conditions: initiator concentration of 20/40 mmole/l for APS/ASBS …
Printing Of Direct Dye On Silk Fabric With Improved Dye Fixation And Wet –Fastness, Wagih Abdallah, Abeer Fath Alla
Printing Of Direct Dye On Silk Fabric With Improved Dye Fixation And Wet –Fastness, Wagih Abdallah, Abeer Fath Alla
Al-Azhar Bulletin of Science
Application of direct dyes on silk fabric suffer from problems of poor fastness properties as well as decrease in dye fixation .A formaldehyde donor agent, i.e. Hexamine, (hexamethylene tetramine), was used for improving dye fixation and wet fastness when added to the printing paste during printing silk fabric with a direct dye containing free amino groups (Diamine Supra Blue GRL200% ).
Inhibition Effect Of Some Polyethylene Glycols (Peg) On The Corrosion Of Aluminum In 1.0 M Phosphoric Acid, S. Soliman
Inhibition Effect Of Some Polyethylene Glycols (Peg) On The Corrosion Of Aluminum In 1.0 M Phosphoric Acid, S. Soliman
Al-Azhar Bulletin of Science
The effect of some polyethylene glycols (PEG) as inhibitors on the corrosion of aluminum in 1.0 M H3PO4 has been studied using weight loss and polarization measurements in various concentrations of PEG and at different temperatures. The dissolution of aluminum in phosphoric acids increases by increasing temperatures and decreases by increasing the additive concentrations. The inhibition efficienciy values proceed according to the following order of the molecular weights of the used inhibitors PEG 4000 > PEG 2000 > PEG 1500 > PEG 400. For relatively higher molecular weights inhibitor (beginning from 1500) the type of adsorption taking place at the surface of aluminum …
Studies Of The Effect Of Volatile Compounds In Atmosphere Of Greater Cairo Area, M. Emara, S. Soliman, A. Ramadan, H. El-Kordy
Studies Of The Effect Of Volatile Compounds In Atmosphere Of Greater Cairo Area, M. Emara, S. Soliman, A. Ramadan, H. El-Kordy
Al-Azhar Bulletin of Science
Volatile organic compounds (VOCs) have been determined to be human risk factor in urban environments, as well as primary contributors to the formation of photochemical oxidants. Concentrations of VOCs were measured at five monitoring sites located in the greater Cairo area, Egypt, as a part of the air pollution study. On each sampling day, 22 abundant VOCs were collected three times per day (7-9 in the morning, 2-4 afternoon and 8-10 evening) during the period from March 2003 to March 2004, to observe diurnal variations of volatile organic compounds on the air of Greater Cairo area and air quality information …
Preparation Conditions Of Humic Acids From Village's Compost Fuel (Vcf) And Their Effects On Humic Acids Chemical Characteristic Alternation During Isolation Part Ii. Effect Of The Extraction Conditions On The Functional Groups Contents Of Humic Acids As Revealed By Spectroscopic Analysis, M. Badr
Al-Azhar Bulletin of Science
IR spectra of humic acids ( HAs) extracted by NaOH solution under different conditions showed that HAs extracted by 0.1 M after 6h and 16 h have identical finger print regions. These spectra indicate the presence of highest number of functional groups and highest aromatic COOH group content, in comparison with ( HAs) extracted by 0.1M after 2h and 24 h. IR spectrum of humic acids HAs extracted by 0.2M after 2h was generally similar with the two latter spectra. The IR spectra of HAs extracted after 2h by 0.5M, 1M, and 2M not only show the disappearance of aromatic …
The Inhibition Effect Of Some Pyrimidine Derivatives On Corrosion Of Aluminum And Some Of Its Alloys In 2.0 M Hcl Solutions, S. Mahmoud, M. Ahmed
The Inhibition Effect Of Some Pyrimidine Derivatives On Corrosion Of Aluminum And Some Of Its Alloys In 2.0 M Hcl Solutions, S. Mahmoud, M. Ahmed
Al-Azhar Bulletin of Science
In the present study the corrosion of aluminum and some of its alloys in 2M HCl was studied. The effect of some pyrimidine derivatives, as organic inhibitors, on the corrosion of aluminum and its alloys in HCl solution was studied. The techniques used of measurements were: (i) linear polarization (ii) galvanostatic polarization and (iii) electrochemical impedance spectroscopy. The corrosion rate of the investigated electrodes was found to be depended on the type and composition of the metal electrode. The pyrimidine derivatives acted as mixed inhibitors in acidic media. It was found that the inhibition efficiency of the inhibitor greatly depended …
Survey Of Commercial Bottled Drinking Water In Egypt, M. El-Shahat, S. Abd El-Halim, M. El-Sayed, N. Abd El-Fattah
Survey Of Commercial Bottled Drinking Water In Egypt, M. El-Shahat, S. Abd El-Halim, M. El-Sayed, N. Abd El-Fattah
Al-Azhar Bulletin of Science
Inorganic constituents were analyzed in six major brands of commercial bottled water and in six brands of the imported mineral drinking water used by many Egyptians and tourists visiting Egypt. The inorganic analysis included determination of both anion and cation species lead and cadmium. For the purpose of comparison, selected samples of tap water from Cairo were also analyzed. Ion Chromatography (IC) was used for the analysis of anions and cation. Ion selective electrode (ISE) was used for measuring physical constants. Atomic absorption spectrometry was used for the analysis of heavy metals. All water samples (tap water from Cairo and …