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Mohareb R.M.,Cairo University | Ibrahim R.A.,Higher Institute of Engineering and Technology | Wardakhan W.W.,National Organization for Drug Control and Research NODCAR
Medicinal Chemistry Research | Year: 2016

The multi-component reaction of 2-acetylthiophene with aromatic aldehydes and either malononitrile or ethyl cyanoacetate gave the pyran derivatives 4a–4f and pyridine derivatives 5a–5f. On the other hand, the reaction of the 2-acetylthiophene with elemental sulfur and either malononitrile or ethyl cyanoacetate gave the thiophene derivatives 6a and 6b; respectively. Compounds 6a and 6b underwent a series of heterocyclic reactions to give thiazole and thiophene derivatives. All the products were assessed for antitumor activity towards human cancer human gastric cancer (NUGC and HR), human colon cancer (DLD1), human liver cancer (HA22T and HEPG2), human breast cancer (MCF), nasopharyngeal carcinoma (HONE1) cell lines. Compounds 4e, 4f, 5e, 5f, 7b, 8b, 10e, 10f, 11e, 11f, 14d-f, 15d-f, 16a,b and 18b exhibited optimal cytotoxic effect against cancer cell lines, with IC50’s in the nM range. Moreover, 7b, 10e, 14d, 15e and 16b showed no toxicity against shrimp larvae. Anti-proliferative cell activity against cancer cell lines of the most potent compounds showed that compounds 5f and 10e achieved the highest activities among the tested compounds. © 2016 Springer Science+Business Media New York Source

Gaffer H.E.,National Research Center of Egypt | Khalifa M.A.E.,Higher Institute of Engineering and Technology | El-Bially S.F.,National Research Center of Egypt | Metwally M.A.,National Research Center of Egypt | Metwally M.A.,Mansoura University
Macedonian Journal of Chemistry and Chemical Engineering | Year: 2010

Condensation of 2,4-diacarboethoxy-5-hydroxy-3-(4-methoxyphenyl)-5-methyl cyclohexanone (1) with equimolar amounts of hydrazine hydrate and phenyl hydrazine afforded the corresponding 2H-indazole-5-carboxylates 2a and 2b, respectively. Coupling of 2 with diazotized aromatic amines furnished the corresponding azo compounds 3a-n. When compound 1 was subjected to the Japp-Klingemann reaction in alkaline medium with diazotized aromatic amines furnished the corresponding hydrazones 4a-g. The treatment of 4a-g with phenyl hydrazine in acetic acid allows the isolation of arylhydrazono derivatives 5a-g. The structures of the dyes were established using analytical and spectral data. Evaluation of the technical properties and color assessment of the dyes were done. Source

Beshr A.A.A.,Mansoura University | Abo Elnaga I.M.,Higher Institute of Engineering and Technology
Alexandria Engineering Journal | Year: 2011

In order to achieve the results that meet the specifications of a given project, like engineering surveys and deformation measurements, the knowledge of the reliability and accuracy of the surveying equipment is inevitable. Precise digital levels and reflectorless total stations are used nowadays for several applications in geodetic engineering due to their highly accurate and fast measurements in an automated measuring process. A shortcoming is that they give less accurate measurements in some cases of observations. There are several sources of errors which have an effect on the accuracy of staff reading during digital leveling such as the effect of sun, and therefore have to be investigated. The quality and accuracy of measurements of electronic surveying instruments may be affected by the capacity of instrument battery which may be worked for long time in the field. This paper investigates the effect of sun on the accuracy of digital level measurements and investigates also the effect of battery capacity on the accuracy of total station and digital levels observations. The paper is performed also to find out the effect of inclined angle of reflecting surface, its colors and types on the accuracy of reflectorless total station measurements which have a great influence on monitoring the deformation of cylindrical and domical structures. The results of practical measurements, calculations and analysis of the interesting tests using least squares theory and computer programs are also presented. © 2011 Faculty of Engineering, Alexandria University. Production and hosting by Elsevier B.V. All rights reserved. Source

Nasr G.M.,Cairo University | Osman H.M.,Cairo University | Omar M.M.,Cairo University | AbdElbary A.M.,Higher Institute of Engineering and Technology
Life Science Journal | Year: 2014

Thermal properties of the PVC/PMMA loaded conductive polypyrrole composites were analyzed by thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). A decrease in the glass transition temperatures Tg with the conductive PPy concentration content reveals the increase of segmental motion. Dielectric properties of these composites were studied in the frequency range between 100 Hz and 5 MHz at room temperature for various weight percentage of conductive PPy. The x-ray diffractograms of all the samples ensures the amorphous nature of the composites. Source

Mohareb R.M.,Cairo University | Abbas N.S.,Helwan University | Ibrahim R.A.,Higher Institute of Engineering and Technology
Acta Chimica Slovenica | Year: 2013

The reaction of either cyclohexanone or cyclopentanone with cyanoacetylhydrazine and elemental sulfur gave the 2-aminocycloalkeno[b] thiophene derivatives 3a and 3b, respectively. The latter compounds reacted with either aromatic benzaldehydes or active methylene reagents to give the Schiff's bases 5a-d and the pyrazole derivatives 7a-d and 9a-d, respectively. On the other hand, the reaction of 3-oxo-N-p-tolylbutanamide (10) with either of malononitrile or ethyl cyanoacetate gave the thiophene derivatives 13a and 13b, respectively. Compounds 13a,b were subjected to a series of heterocyclization reactions to give heterocyclic derivatives. Their cytotoxicity against the three human tumor cells lines, namely breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268) together against the normal human cell line namely the normal fibroblast cells WI 38 were measured. Source

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