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21.
Les Sels de Bismuth (III) Comme Catalyseurs Dans la Reaction D'ouverture Des Epoxydes Par Les Amines
Adyl Oussaid Bernard Garrigues Boualem Oussaid Fatima Benyaquad 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2315-2320
BiCl 3 and Bi (OTf) 3 catalyze the opening of epoxides ( 1-7 ) by amines ( 8-12 ). High regioselectivities are observed. BiCl 3 et Bi (OTf) 3 catalysent la réaction d'ouverture des époxydes ( 1-7 ) par les amines ( 8-12 ). La réaction est fortement régiosélective. 相似文献
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23.
Zouaoui Setifi Mehdi Boutebdja Fatima Setifi Hocine Merazig Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(7):702-706
In the title compound, catena‐poly[bis[(2,2′‐bipyridine‐κ2N,N′)(1,1,3,3‐tetracyano‐2‐ethoxypropenido‐κN)copper(II)]‐μ4‐hexanedioato‐κ6O1,O1′:O1:O6,O6′:O6], [Cu2(C9H5N4O)2(C6H8O4)(C10H8N2)2]n, the adipate (hexanedioate) dianion lies across a centre of inversion in the space group P. The CuII centre adopts a distorted form of axially elongated (4+2) coordination, and the CuII and adipate components form a one‐dimensional coordination polymer from which the 2,2′‐bipyridine and 1,1,3,3‐tetracyano‐2‐ethoxypropenide components are pendent, and where each adipate dianion is bonded to four different CuII centres. The coordination polymer chains are linked into a three‐dimensional framework structure by a combination of C—H...N and C—H...O hydrogen bonds, augmented by a π–π stacking interaction. 相似文献
24.
Fatima Flores-Galicia Alexander Eden Antoine Pallandre Sumita Pennathur Anne-Marie Haghiri-Gosnet 《Electrophoresis》2022,43(5-6):741-751
We report on the investigation of electropreconcentration phenomena in micro-/nanofluidic devices integrating 100 μm long nanochannels using 2D COMSOL simulations based on the coupled Poisson–Nernst–Planck and Navier–Stokes system of equations. Our numerical model is used to demonstrate the influence of key governing parameters such as electrolyte concentration, surface charge density, and applied axial electric field on ion concentration polarization (ICP) dynamics in our system. Under sufficiently extreme surface-charge-governed transport conditions, ICP propagation is shown to enable various transient and stationary stacking and counter-flow gradient focusing mechanisms of anionic analytes. We resolve these spatiotemporal dynamics of analytes and electrolyte ICP over disparate time and length scales, and confirm previous findings that the greatest enhancement is observed when a system is tuned for analyte focusing at the charge, excluding microchannel, nanochannel electrical double layer (EDL) interface. Moreover, we demonstrate that such tuning can readily be achieved by including additional nanochannels oriented parallel to the electric field between two microchannels, effectively increasing the overall perm-selectivity and leading to enhanced focusing at the EDL interfaces. This approach shows promise in providing added control over the extent of ICP in electrokinetic systems, particularly under circumstances in which relatively weak ICP effects are observed using only a single channel. 相似文献
25.
Sherif Aly El-Kafrawy Sayed Sartaj Sohrab Zeenat Mirza Ahmed M. Hassan Fatima Alsaqaf Esam Ibraheem Azhar 《Molecules (Basel, Switzerland)》2021,26(9)
MERS-CoV was identified for the first time in Jeddah, Saudi Arabia in 2012 in a hospitalized patient. This virus subsequently spread to 27 countries with a total of 939 deaths and 2586 confirmed cases and now has become a serious concern globally. Camels are well known for the transmission of the virus to the human population. In this report, we have discussed the prediction, designing, and evaluation of potential siRNA targeting the ORF1ab gene for the inhibition of MERS-CoV replication. The online software, siDirect 2.0 was used to predict and design the siRNAs, their secondary structure and their target accessibility. ORF1ab gene folding was performed by RNAxs and RNAfold software. A total of twenty-one siRNAs were selected from 462 siRNAs according to their scoring and specificity. siRNAs were evaluated in vitro for their cytotoxicity and antiviral efficacy in Huh7 cell line. No significant cytotoxicity was observed for all siRNAs in Huh7 cells. The in vitro study showed the inhibition of viral replication by three siRNAs. The data generated in this study provide preliminary and encouraging information to evaluate the siRNAs separately as well as in combination against MERS-CoV replication in other cell lines. The prediction of siRNAs using online software resulted in the filtration and selection of potential siRNAs with high accuracy and strength. This computational approach resulted in three effective siRNAs that can be taken further to in vivo animal studies and can be used to develop safe and effective antiviral therapies for other prevalent disease-causing viruses. 相似文献
26.
Fatima Gul Naz Paliwal Sarvesh K. Saraf Shailendra K. 《Russian Journal of General Chemistry》2021,91(2):285-293
Russian Journal of General Chemistry - A number of novel 7-chloro-4-aminoquinoline derivatives have been efficiently synthesized by nucleophilic aromatic substitution reaction of... 相似文献
27.
Syed Sarim Imam Sultan Alshehri Mohammad A. Altamimi Afzal Hussain Wajhul Qamar Sadaf Jamal Gilani Ameeduzzafar Zafar Nabil K. Alruwaili Saleh Alanazi Bjad K. Almutairy 《Molecules (Basel, Switzerland)》2021,26(11)
The present research work is designed to prepare and evaluate piperine liposomes and piperine–chitosan-coated liposomes for oral delivery. Piperine (PPN) is a water-insoluble bioactive compound used for different diseases. The prepared formulations were evaluated for physicochemical study, mucoadhesive study, permeation study and in vitro cytotoxic study using the MCF7 breast cancer cell line. Piperine-loaded liposomes (PLF) were prepared by the thin-film evaporation method. The selected liposomes were coated with chitosan (PLFC) by electrostatic deposition to enhance the mucoadhesive property and in vitro therapeutic efficacy. Based on the findings of the study, the prepared PPN liposomes (PLF3) and chitosan coated PPN liposomes (PLF3C1) showed a nanometric size range of 165.7 ± 7.4 to 243.4 ± 7.5, a narrow polydispersity index (>0.3) and zeta potential (−7.1 to 29.8 mV). The average encapsulation efficiency was found to be between 60 and 80% for all prepared formulations. The drug release and permeation study profile showed biphasic release behavior and enhanced PPN permeation. The in vitro antioxidant study results showed a comparable antioxidant activity with pure PPN. The anticancer study depicted that the cell viability assay of tested PLF3C2 has significantly (p < 0.001)) reduced the IC50 when compared with pure PPN. The study revealed that oral chitosan-coated liposomes are a promising delivery system for the PPN and can increase the therapeutic efficacy against the breast cancer cell line. 相似文献
28.
The Use of Poly(Vinyl Alcohol) to Cross‐link Penicillinase for the Fabrication of a Penicillin Potentiometric Biosensor 下载免费PDF全文
Chemically cross‐linked PVA films are permeable matrices for the fabrication of biosensors. PVA provides an attractive immobilisation method as it preserves the enzymatic activity. Penicillinase (P’nase) was cross‐linked with poly(vinyl alcohol) (PVA) and bovine serum albumin (BSA). The optimum conditions for the of BSA‐PVA‐P’nase film were: 2.5 % w/v PVA, 0.006 % w/v BSA, 2.4 mM penicillin (Pen) and 16 U/mL P’nase. The minimum detectable concentration was 1.7 µM. The linear concentration range obtained for the BSA‐PVA film was 7.5–283 µM. The BSA‐PVA P’nase biosensor detected penicillin in amoxycillin with an average percentage recovery of 97±12 %. Higher penicillin concentrations (10–20 ppm) were detected more successfully than lower concentrations (≤5 ppm). These results indicate that further work is required to enable the successful detection of lower penicillin concentrations such as 5 ppm. 相似文献
29.
Sajid Muhammad Munir Shad Naveed Akthar Javed Yasir Khan Sadaf Bashir Zhang Zhengjun Amin Nasir 《Research on Chemical Intermediates》2020,46(2):1201-1215
Research on Chemical Intermediates - We prepared unique BiVO4/reduce graphene oxide (BiVO4/rGO) nanocomposite with enhanced photocatalytic ability by hydrothermal method applying... 相似文献
30.
The objective of this work was to prepare the mechanically stable hydrophobic biocomposites by incorporating the cellulose fibers into the polymer matrices for their applications in biomedical and food packaging. Herein, two different types of biocomposites were prepared by mixing polylactic acid (PLA) and polyhydroxybutyrate (PHB) with the agro-extracted cellulose, separately at 170 °C. The influence of the cellulose fibers on the thermal, mechanical, and barrier properties of polymer matrices (PLA and PHB) was observed. With an increase in the cellulose content in PLA and PHB, the tensile strength of the biocomposite materials significantly improved with the enhancement of 24.45% and 32.08%, respectively, compared with the pure PLA and PHB. Furthermore, a decrease of 74.16% and 73.49% in the water vapor transmission rate and oxygen transmission rate, respectively, was observed for cellulose/PHB biocomposites. This study highlights that adding cellulose fibers significantly improves the mechanical and the barrier properties of PLA and PHB, suggesting their biocomposites for use in biodegradable polymer industries. 相似文献