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Search Results: 1 - 10 of 8909 matches for " Mohamed Zahouily "
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I2/Nanostructured Pyrophosphate : A Mild and Efficient Catalyst for the Selective Protection of Carbonyl Compounds  [PDF]
Asmae Lemaanni, Asmae Snik, Karima Abdelouahdi, Abderrahim Solhy, Mohamed Zahouily
Modern Research in Catalysis (MRC) , 2012, DOI: 10.4236/mrc.2012.12003
Abstract: A new solvent free method for protection of carbonyl compounds as their thioacetals has been accomplished through the use of iodine supported on nanostructured pyrophosphate. Advantages of the methodology include very short reaction time, the requirement for minimum amounts of catalyst, the remarkably simple experimental procedure, and no necessity for solvents or inert atmospheres, excellent yields and recyclability of the catalyst used. An efficient method for the chemoselective thioacetalization of ketones in the presence of aldehydes using I2/nanostructured pyrophosphate is also reported in this article. The nanostructured pyrophosphate was characterized by scanning electron microscopy, X-ray diffraction, infrared spectroscopy, Transmission electron microscopy and thermal gravimetric analysis, respectively.
Using Multiple Linear Regression and Artificial Neural Network Techniques for Predicting CCR5 Binding Affinity of Substituted 1-(3, 3-Diphenylpropyl)-Piperidinyl Amides and Ureas  [PDF]
Rokaya Mouhibi, Mohamed Zahouily, Khalid El Akri, Na?ma Hanafi
Open Journal of Medicinal Chemistry (OJMC) , 2013, DOI: 10.4236/ojmc.2013.31002
Abstract:

Quantitative structure–activity relationship (QSAR) models were developed to predict for CCR5 binding affinity of substituted 1-(3, 3-diphenylpropyl)-piperidinyl amides and ureas using multiple linear regression (MLR) and artificial neural network (ANN) techniques. A model with four descriptors, including Hydrogen-bonding donors HBD(R7), the partition coefficient between n-octanol and water logP and logP(R1) and Molecular weight MW(R7), showed good statistics both in the regression and artificial neural network with a configuration of (4-3-1) by using Bayesian and Leven-berg-Marquardt Methods. Comparison of the descriptor’s contribution obtained in MLR and ANN analysis shows that the contribution of some of the descriptors to activity may be non-linear.

Sodium-Modified Fluorapatite: A Mild and Efficient Reusable Catalyst for the Synthesis of α,α’-Bis(Substituted Benzylidene) Cycloalkanones under Conventional Heating and Microwave Irradiation  [PDF]
Bahija Mounir, Fathallaah Bazi, Abddelfetah Mounir, Mohamed Zahouily, Hamid Toufik
Green and Sustainable Chemistry (GSC) , 2018, DOI: 10.4236/gsc.2018.82011
Abstract: A versatile and environmentally friendly method for α,α’-bis(substituted ben-zylidene) cycloalkanones has been developed using a heterogeneous catalysis technology. We have synthesized a series of the α,α’-bis(substituted benzylidene) cycloalkanones, a biologically important class of compounds, via the cross aldol condensation between arylaldehydes and cycloketones using sodium-modified fluorapatite (Na/FAP) as a highly efficient solid catalyst under conventional heating in aqueous media and solventless conditions under microwave. Catalyst reuse, ease of separation of the pure product, and high yields are some of the unique features of this process. Shorter reaction times (4 - 7 min) and higher yields (80% - 94%) were achieved under microwave irradiation conditions.
Physicochemical 2D-Qsar and 3D Molecular Docking Studies on N-Chlorosulfonyl Isocyanate Analogs as Sterol O-Acyl-Transferase-1 “Soat-1” Inhibitors  [PDF]
Khalid El Akri, Rokaya Mouhibi, Mohamed Zahouily, Na?ma Hanafi, Moulay Abdellah Bahlaoui
Open Journal of Medicinal Chemistry (OJMC) , 2013, DOI: 10.4236/ojmc.2013.34013
Abstract: A series of N-carbonyl-functionalized ureas, carbamates and thiocarbamates derivatives (or N-Chloro sulfonyl isocyanate
“N-CSI”) were involved in linear and nonlinear physicochemical quantitative structure-activity relationship
“QSAR” analysis to find out the structural keys to control the inhibition against Sterol O-Acyl-Transferase-1 “SOAT-1”.
The results indicate the important effects of geometrical and chemical descriptors on the inhibitory activity of SOAT-1.
The molecules were also screened for three-dimensional molecular docking on the crystal structure of ACAT-1 (1WL5
for ACAT-1, PDB). A comparison between 2D-QSAR and 3D molecular docking studies shows that the latter confirm
the first results and represent a good prediction of the chemical and physical nature of interactions between our drug
molecules and enzyme SOAT-1.
Experimental Design-Based Response Surface Methodology Optimization for Synthesis of β-Mercapto Carbonyl Derivatives as Antimycobacterial Drugs Catalyzed by Calcium Pyrophosphate
Younes Abrouki,Abdelkader Anouzla,Hayat Loukili,Jamal Bennazha,Rabiaa Lotfi,Ahmed Rayadh,My Abdellah Bahlaoui,Sa?d Sebti,Driss Zakarya,Mohamed Zahouily
International Journal of Medicinal Chemistry , 2014, DOI: 10.1155/2014/586437
Abstract: A simple protocol for the efficient preparation of β-mercapto carbonyl derivatives as antimycobacterial drugs has been achieved via Thia-Michael reaction between chalcones derivatives and thiols in the presence of calcium pyrophosphate as a heterogeneous catalyst under mild reaction conditions. The central composite design was used to design an experimental program to provide data to model the effects of various factors on reaction yield . The variables chosen were catalyst weight , reaction time , and solvent volume . The mathematical relationship of reaction yield on the three significant independent variables can be approximated by a nonlinear polynomial model. Predicted values were found to be in good agreement with experimental values. The optimum reaction conditions for reaction model (chalcone and thiophenol) obtained by response surface were applied to other substrates. This procedure provides several advantages such as high yield, clean product formation, and short reaction time. 1. Introduction Tuberculosis is the second most common cause of death from infectious disease. Roughly one-third of the world’s population has been infected with Mycobacterium tuberculosis, and new infections occur at a rate of one per second. In 2007 there were an estimated 13.7 million chronic active cases, and in 2010 there were 8.8 million new cases and 1.45 million deaths. 0.35 million of these deaths occur in those coinfected with HIV [1]. The needs of newly developed antimycobacterial drugs are required for the control of tuberculosis in the present time. In the discovery of new antimycobacterial drugs, the emergence of multidrug-resistant and extensively drug-resistant strains of Mycobacterium has encouraged the researchers to intensify the efforts to discover novel drugs [2]. Recently, the Czech authors showed that the 1,3-diphenyl-3-arylsulfenylpropan-1-one derivatives presented an antimycobacterial activity [3]. Thia-Michael reaction is a convenient route for synthesis of these β-mercapto carbonyl derivatives [4]. Traditionally, this reaction is catalyzed by strong bases [5] such as alkali metal alkoxides, hydroxides, and amines. However the use of either strongly acidic or basic conditions frequently leads to the formation of undesirable side products owing to competing reactions, such as polymerization, self-condensation, and rearrangements. The development of solid basic catalysts which could replace the liquid bases currently used in industrial processes is a major field of today’s catalysis research [6]. In this paper we report a mild and convenient
The Effects of Residual Blood of Carcasses on Poultry Technological Quality  [PDF]
Bourbab Mohamed, Idaomar Mohamed
Food and Nutrition Sciences (FNS) , 2012, DOI: 10.4236/fns.2012.310181
Abstract: The objective of this work is to show the effect of residual blood on the quality of chicken meat, work based on the hypothesis that increasing the concentration of residual blood would explain the observed quality degradation by several authors. Lots of chickens are killed with two different types of slaughter: Slaughter without stunning for a maximum flow of blood or bleeding perfect PS, shooting seals slight lead to keep almost all blood from the carcass or bleeding IS flawed. To prove the residual blood factors that are responsible for high pHu level and high values of (L* A* B*) in poultry, this study compares the pHu level and values of (L* A* B*) in poultry both perfectly and imperfectly bled. Samples from imperfectly bled carcasses show a high value average number of A* = 12.68 and B* = 16.85; and L* = 54.09 VS the average number of A* = 8.50 and B* = 14.43 and L* = 50.27. At 3℃ storage temperature, the average pHu of perfectly bled poultry was (5.7) which was significantly (P < 0.01) lower than the average pHu of imperfectly bled poultry (6.08). At 7℃ storage temperature, the average pHu of perfectly bled poultry was (6.07) which was significantly (P < 0.05) lower than the average pHu of imperfectly bled one (6.27). We found out the effect of season on the results of pHu measures, so we conducted aanalysis of pHu in summer and winter. Residual blood of the poultry is responsible for high values of (L* A* B*) and high values of pHu therefore the deterioration of the poultry Colour.
Monitoring of Temporal and Spatial Changes of Land Use and Land Cover in Metropolitan Regions through Remote Sensing and GIS  [PDF]
Mohamed Ali Mohamed
Natural Resources (NR) , 2017, DOI: 10.4236/nr.2017.85022
Abstract: The use of remote sensing techniques and subsequent analysis by means of geographical information system (GIS) offers an effective method for monitoring temporal and spatial changes of landscapes. This work studies the urbanization processes and associated threats to natural ecosystems and resources in the metropolitan areas of Berlin and Erlangen-Fürth-Nürnber?Schwabach (EFNS). To compute the land use/cover (LULC) of the study areas, a supervised classification of “maximum likelihood” using Landsat data for the years of 1972, 1985, 1998, 2003, and 2015 is used. Results show that the built-up area is the dominant land use in both regions throughout the study period. This land use has increased at the expense of green and open areas in EFNS and at the expense of agricultural land in Berlin. Likewise, 5% of forest in EFNS is replaced with urban infrastructure. However, the amount of forest in Berlin increased by 3%. While EFNS experienced relatively big changes in its water bodies from 1972 to 1985, changes in water bodies in Berlin were rather slight during the last 40 years. The overall accuracy of our remotely sensed LULC maps was between 88% and 94% in Berlin and between 85.87% and 87.4% for EFNS. The combination of remote sensing and GIS appears to be an indispensable tool for monitoring changes in LULC in urban areas and help improving LU planning to avoid environmental and ecological problems.
Analysis of Digital Elevation Model and LNDSAT Data Using Geographic Information System for Soil Mapping in Urban Areas  [PDF]
Mohamed Ali Mohamed
Natural Resources (NR) , 2017, DOI: 10.4236/nr.2017.812047
Abstract:
This study applies digital analysis methods of topographic data derived from digital elevation models (DEMs) and Landsat remotely sensed spectral data using GIS tools to evaluate the quality and limitations of the morphometric parameters (terrain attributes: TAs). This aims to check its suitability for digital soil mapping (DSM) and survey in urban areas at the target scale 1:50,000. This scale represents the standard scale level for compiling soil inventories within all German states. The study is conducted on an urban area of 112.68 km2 in the southwest part of the state of Berlin in Germany. These relief units are the basis for determining the soil mapping units at the scale of 1:50,000. The generated preliminary soil map was compared to soil maps made using traditional soil survey methods. For the mainly natural soils, the equivalence area is 94.91%, and for the anthropogenic soils, the equivalence area is 95.34%. The proposed methodology is adequate for preliminary mapping of soil units based on the digital derivation of TAs. Landsat scenes are spatially explicit, physical representations of environmental covariates on the land surface. The free DEM-ASTER in combination with Landsat OLI images is found to be the appropriate model to represent the terrain surface and derive the TAs for environmental modeling and fitting of derivation the relief units and their topography features. However, the 30 m spatial resolution and the fairly coarse spectral resolution of DEMs and Landsat images limit their utility for digital soil mapping at this scale in urban areas with little topographic variation.
Effect of Nalbuphine as Adjuvant to Bupivacaine for Ultrasound-Guided Supraclavicular Brachial Plexus Block  [PDF]
Mohamed Mohamed Abdelhaq, Mohamed Adly Elramely
Open Journal of Anesthesiology (OJAnes) , 2016, DOI: 10.4236/ojanes.2016.63004
Abstract: Background: Nalbuphine is a derivative of 14-hydroxymorphine which is a strong analgesic with mixed k agonist and μ antagonist. Nalbuphine was studied several times as adjuvant to local anesthetics in spinal, epidural and local intravenous block. The aim of this study was to evaluate the effect of nalbuphine as an adjuvant to local anesthetics in supraclavicular brachial plexus block. Patients and Methods: Fifty-six patients undergoing elective forearm and hand surgery under supraclavicular brachial plexus block were allocated randomly into one of two groups of 28 patients each to receive either 25 ml (0.5%) bupivacaine with 1 ml of NS or 25 ml (0.5%) bupivacaine with 1 ml (20 mg) nalbuphine. Onset time and duration of both sensory and motor block, and post-operative analgesia were observed. Result: Nalbuphine group showed significant increase in the duration of motor block (412.59 ± 18.63), when compared to control group (353.70 ± 29.019) p-value < 0.001, also, there was significant increase in sensory duration in nalbuphine group (718.14 ± 21.04) when compared to control group (610.18 ± 26.33) p-value < 0.001, without affecting the onset time of the blockade. And also, there was a significant increase in the duration of analgesic effect in nalbuphine group (835.18 ± 42.45) when compared to control group (708.14 ± 54.57) p-value < 0.001. Conclusion: The present study demonstrates that addition of 20 mg nalbuphine to bupivacaine in supraclavicular brachial plexus block is associated with significant increase in the duration of both sensory and motor block and also prolong the duration of analgesia.
Impact profenophos (pesticide) on infectivity of Biomphalaria alexandrina snails with schistosoma mansoni miracidiaand on their physiological parameters  [PDF]
Ragaa Mohamed
Open Journal of Ecology (OJE) , 2011, DOI: 10.4236/oje.2011.12005
Abstract: Profenophos is an organophosphorus pesticide which are used effectively against cotton insects and mites.The present work was carried out to evaluate the molluscicidal activity of pesticides (Profenophos) against Biomphalaria alexandrina snails. Also, the effect of sublethal concentrations of pesticide on the infection of B. alexandrina with Schistosoma mansoni and some enzymes of energy metabolism were studied. The results showed that the infection of B. alexandrina with schistosoma mansoni was greatly reduced after exposure to LC0, LC10, LC25 of pesticide and also, reduction in number of cercariae per snail during the patent period and in the period of cercarial shedding. The present study indicated that the increase in levels of aminotransaminases, acid phosphatase and alkaline phosphatases enzymes in haemolymph and soft tissue of snails and the activity level of lactate dehydrogenase, hexokinase and pyruvatekinase was also significantly reduced in response to treatment.
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