Publications by authors named "Galal A Nawwar"

The compounds 2',3',4',6'-tetra--acetyl-β-d-gluco-pyranosyl '-cyano--phenyl-carbamimido-thio-ate (CHNOS, ), 2',3',4',6'-tetra--acetyl-β-d-galacto-pyranosyl '-cyano-phenyl-carbamimido-thio-ate, (CHNOS, ), 2',3',4',6'-tetra--acetyl-β-d-galacto-pyranosyl '-cyano--methyl-carbamimido-thio-ate (CHNOS, ), and 2',3',4',6'-tetra--acetyl-β-d-galacto-pyranosyl '-cyano---tolyl-carbamimido-thio-ate (CHNOS, ) all crystallize in 222 with = 4. For all four structures, the configuration across the central (formal) C=N(CN) double bond of the carbamimido-thio-ate group is . The torsion angles C5-O1-C1-S (standard sugar numbering) are all close to 180°, confirming the β position of the substituent.

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This study reports a novel and efficient method for the synthesis of the first reported novel class of triazole thioglycosides. These series of compounds were designed through the reaction of potassium cyanocarbonimidodithioate 2 with hydrazine derivatives 3a-d in EtOH at room temperature to give the corresponding potassium 5-amino-1H-1,2,4-triazole-3-thiolates 4a-d. The latter compounds were treated with tetra-O-acetyl-α-D-glucopyranosyl bromide 6a and tetra-O-acetyl-α-D-galactopyranosyl bromide 6b in DMF at room temperature to give in high yields the corresponding triazole thioglycosides 7a-h.

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HER1 and HER2 are frequently overexpressed in human tumors where they drive cellular proliferation. For this reason they are considered important targets in anticancer therapy with dual HER1/HER2 inhibitors being recently approved and marketed. In this paper we report the identification of a series of compounds with anticancer activity by a combined virtual screening approach on the kinase domains of HER1 and HER2.

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West Nile virus (WNV) is a human pathogen which is rapidly expanding worldwide. It is a member of the Flavivirus genus and it is transmitted by mosquitos between its avian hosts and occasionally in mammalian hosts. In humans the infection is often asymptomatic, however, the most severe cases result in encephalitis or meningitis.

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Objective: To evaluate some agricultural waste extracts as insecticide and their effects on enzyme activities in liver and kidney of male mice.

Methods: The insecticidal activity of five tested compounds (one crude extract and 4 waste compounds) was bioassay against the 3rd instars of the Culex pipiens (Cx. pipiens) larvae in the laboratory.

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Pyridines containing the galloyl moiety have been prepared utilizing 4-acetyl pyrogallol. In addition, fused pyridines were synthesized from the obtained pyridines via further chemical transformations. The results indicated that compound 4a showed stronger DPPH scavenging activity than the other compounds, and the scavenging effect decreased in the following order 4a > t-BHQ > 2a > 2b > 3a > 3b > 4b.

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Several 2-thioglycosides were prepared. Glycosylation of 2-thioxo-thieno[2,3-d]-pyrimidines 5a,b with 1-bromo-2,3,5-tri-O-acetyl-alpha-d-arabinofuranosyle 7, 2,3,4,6-tetra-O-acetyl-alpha-d-glucopyranosyl and galacto-pyranosyl bromide 8a,b gave the protected beta-d-nuclosides 10a,b and 13a-d in high yields, which were transformed to deacetylated derivatives 14a,b and 15a-d. The structures of the compounds were elucidated by spectral and elemental analysis.

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