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121.
122.
A low‐cost and highly effective zinc/THF‐saturated aqueous ammonium chloride has been developed for dehalogenation of arylhalides and alkylhalides in aqueous systems. 相似文献
123.
Synthesis,Enzyme Inhibition,and Molecular Docking Studies of Hydrazones from Dichlorophenylacetic Acids 下载免费PDF全文
Obaid‐ur‐Rahman Abid Muhammad Ayaz Wajid Rehman Kamran Mehdi Arif Ali Abdul Wadood Fazal Rahim Aneesa Sultan Mehreen Ghufran Sadullah Mir Muhammad Tauseef Qureshi 《中国化学会会志》2016,63(12):1015-1021
A series of hydrazones 5a–i were synthesized by the condensation of hydrazides derived from dichlorophenylacetic acids with different aromatic aldehydes and ketones. Their structures were confirmed by spectroscopic data and elemental analysis. Hydrazones 5a–i were evaluated for α‐glucosidase and urease inhibition activities. Five compounds exhibited potent α‐glucosidase inhibitory potential with IC50 values 8.5 ± 0.3, 22.2 ± 0.78, 32.9 ± 1.5, 34 ± 2.4, and 170.6 ± 7.5 μM, respectively, which are many times better than that of the standard inhibitor acarbose (IC50 = 840 ± 1.73 μM). Furthermore, molecular docking study was performed to explore the binding mode in the active sites of α‐glucosidase and urease enzymes. 相似文献
124.
A stoichiometric imprinted chelating resin for selective recognition of copper(II) ions in aqueous media 总被引:1,自引:0,他引:1
Shamsipur M Fasihi J Khanchi A Hassani R Alizadeh K Shamsipur H 《Analytica chimica acta》2007,599(2):294-301
This work reports the preparation of a new copper(II) ion-imprinted polymer (IIP) material, using 5,6;14,15-dibenzo-1,4-dioxa-8,12-diazacyclopentadecane-5,14-diene (DBDA15C4) and 2-vinylpyridine (VP) as a non-vinylated chelating agent and a functional vinyl monomer, respectively. The Cu2+ ion can form stable complexes with DBDA15C4 and VP. The stoichiometries of Cu2+-DBDA15C4 and ternary Cu2+-DBDA15C4-VP complexes were elucidated using conductometric and spectrophotometric methods, and found to be Cu2+(DBDA15C4), Cu2+(DBDA15C4)2 and Cu2+(DBDA15C4)(VP)2. The results obtained from solution studies were also supported by ab initio theoretical calculations. The resulting ternary complex Cu2+(DBDA15C4)(VP)2 was copolymerized with ethyleneglycoldimethacrylate, as a cross-linking monomer, via bulk polymerization method. The imprinted copper ion was removed from the polymeric matrix by 0.1 M HNO3. The Cu2+-imprinted polymer particles were characterized by IR spectroscopy and elemental analysis. Optimum pH range for rebinding of Cu2+ on the IIP and equilibrium binding time were 7.0-7.5 and 45 min, respectively. Sorbent capacity and enrichment factor for Cu2+ were obtained as 75.3 ± 1.9 μmol g−1 and 100, respectively. In selectivity study, it was found that imprinting results in increased affinity of the material toward Cu2+ ion over other competitor metal ions with the same charge and close ionic radius. The prepared IIPs were repeatedly used and regenerated for five times without a significant decrease in polymer binding affinities. 相似文献
125.
Ullah Hayat Ullah Hafeez Taha M. Khan F. Rahim F. Uddin I. Sarfraz M. Shah S. A. Ali Aziz A. Mubeen S. 《Russian Journal of Organic Chemistry》2021,57(6):968-975
Russian Journal of Organic Chemistry - New benzimidazole derivatives were synthesized by reacting substituted phenacyl bromides with 1H-benzimidazole-2-thiols. The synthesized compounds were... 相似文献
126.
Nurul Fattin Che Rahim Yazmin Hussin Muhammad Nazirul Mubin Aziz Nurul Elyani Mohamad Swee Keong Yeap Mas Jaffri Masarudin Rasedee Abdullah Muhammad Nadeem Akhtar Noorjahan Banu Alitheen 《Molecules (Basel, Switzerland)》2021,26(5)
Colorectal cancer (CRC) is the third most common type of cancer worldwide and a leading cause of cancer death. According to the Malaysian National Cancer Registry Report 2012–2016, colorectal cancer was the second most common cancer in Malaysia after breast cancer. Recent treatments for colon cancer cases have caused side effects and recurrence in patients. One of the alternative ways to fight cancer is by using natural products. Curcumin is a compound of the rhizomes of Curcuma longa that possesses a broad range of pharmacological activities. Curcumin has been studied for decades but due to its low bioavailability, its usage as a therapeutic agent has been compromised. This has led to the development of a chemically synthesized curcuminoid analogue, (2E,6E)-2,6-bis(2,3-dimethoxybenzylidine) cyclohexanone (DMCH), to overcome the drawbacks. This study aims to examine the potential of DMCH for cytotoxicity, apoptosis induction, and activation of apoptosis-related proteins on the colon cancer cell lines HT29 and SW620. The cytotoxic activity of DMCH was evaluated using the [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) cell viability assay on both of the cell lines, HT29 and SW620. To determine the mode of cell death, an acridine orange/propidium iodide (AO/PI) assay was conducted, followed by Annexin V/FITC, cell cycle analysis, and JC-1 assay using a flow cytometer. A proteome profiler angiogenesis assay was conducted to determine the protein expression. The inhibitory concentration (IC50) of DMCH in SW620 and HT29 was 7.50 ± 1.19 and 9.80 ± 0.55 µg/mL, respectively. The treated cells displayed morphological features characteristic of apoptosis. The flow cytometry analysis confirmed that DMCH induced apoptosis as shown by an increase in the sub-G0/G1 population and an increase in the early apoptosis and late apoptosis populations compared with untreated cells. A higher number of apoptotic cells were observed on treated SW620 cells as compared to HT29 cells. Human apoptosis proteome profiler analysis revealed upregulation of Bax and Bad proteins and downregulation of Livin proteins in both the HT29 and SW620 cell lines. Collectively, DMCH induced cell death via apoptosis, and the effect was more pronounced on SW620 metastatic colon cancer cells, suggesting its potential effects as an antimetastatic agent targeting colon cancer cells. 相似文献
127.
A series of novel 1-(2'-α-O-D-glucopyranosyl ethyl) 2-arylbenzimidazoles has been prepared via one-pot glycosylation of ethyl-1-(2'-hydroxyethyl)-2-arylbenzimidazole-5-carboxylate derivatives. Synthesis of the 2-arylbenzimidazole aglycones from 4-fluoro-3-nitrobenzoic acid was accomplished in four high-yielding steps. The reduction and cyclocondensation steps for the aglycone synthesis proceeded efficiently under microwave irradiation to afford the appropriate benzimidazoles in excellent yields within 2-3 min. Glycosylation of the hydroxyethyl aglycones with the perbenzylated 1-hydroxy- glucopyranose, pretreated with the Appel-Lee reagent, followed by catalytic hydrogenolysis delivered the desired 1-(2'-α-O-D-glucopyranosyl ethyl) 2-aryl-benzimidazoles in a simple and straightforward manner. 相似文献
128.
Morteza SaberiKamarposhti Dzulkifli Mohammad Mohd Shafry Mohd Rahim Mahdi Yaghobi 《Nonlinear dynamics》2014,75(3):407-416
Recently, image encryption has emerged as an extremely urgent need to provide high protection for secure images against being used without any authorization. In the present paper, the 3-cell chaotic map known as cycling chaos was employed for image encryption based on biological operations. In order to increase security of the proposed method, the 120-bits secret key is used. DNA Sequences and cycling chaos were used to scramble the positions of the image pixels, and then the pixels grey values were modified using a mask DNA generated by cycling chaos. The obtained results demonstrated high security of the proposed method, and it was found acceptably resistant against different well-known attacks. 相似文献
129.
Medhat H. Rahim 《International Journal of Mathematical Education in Science & Technology》2013,44(1):144-150
In this note, a new proof of the Pythagorean Theorem will be presented using only a compass and an unmarked straight edge. As a background, interesting dissection proofs of the Hindu mathematician Bhaskara and the Arabic scholar Tabit ibn-Qorra are highlighted. 相似文献
130.
A.H.M.A. Rahim M.T. Hussain 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(3):201-219
Large participation of renewable energy sources with rapidly varying inputs can affect the performance of a microgrid system. This article develops a detailed non-linear and small-signal dynamic model of a microgrid that includes photovoltaic (PV), wind and conventional small-scale generation along with their power electronics interfaces and the filters. The role of the extent of generation mix of the distributed generators (DGs) for satisfactory operation of the system has been investigated through small-signal dynamic model. It was observed that there exist critical values of PV and wind power above which the microgrid performance degrades. The enhancement of performance of the microgrid through various control inputs have been evaluated through decomposition techniques. Simulation studies showed that an energy storage system-based central supervisory controller and also control of PV system can improve transient performance when violations of proper generation mix of the DGs occur. 相似文献