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951.
Abdelrahman A. Dahy Eida S. Al-Farrag Nourah S. Al-Hokbany 《Journal of Coordination Chemistry》2016,69(6):1088-1099
This article presents a combined experimental and computational study of a new oxorhenium(V) complex of thiazolidine-2,4-dione (HTDO). The complex has been synthesized by direct reaction of NH4ReO4 with thiazolidine-2,4-dione in the presence of Na2S2O6 as a reducing agent. The complex [ReO(TDO)(H2O)3](S2O8) has been characterized by spectroscopy (FT-IR, NMR, UV-vis, mass), thermogravimetry, microanalysis, and HPL chromatography. The complex was geometrically optimized by DFT with B3LYP level of theory and satisfactory theoretical–experimental agreement was achieved for analysis of IR and NMR data of the complex. Additional information about binding between rhenium and oxo ligand in the complex has been obtained by NBO analysis. The antibacterial activity of the investigated complex has been tested and evaluated. 相似文献
952.
The chemistry of 1,2,5-triazepines and related compounds is reported. The investigated heterocycles are monocyclic and fused 1,2,5-triazepines. The different sections cover the synthesis and reactions of monocyclic and fused heterocycles incorporating 1,2,5-triazepine ring systems. This review also covers modifications of the 1,2,5-triazepines into many useful ring systems using a host of reagents and other multistep transformations. The biological evaluation of the target compounds is described, as well as the synthetic applications. The reaction mechanisms are discussed. 相似文献
953.
Microwave‐Assisted Synthesis of Arylazoaminopyrazoles as Disperse Dyes for Textile Printing 下载免费PDF全文
Tawfik A. Khattab Karima M. Haggag Mohamed H. Elnagdi Amal A. Abdelrahman Sherif Abdelmoez Aly 《无机化学与普通化学杂志》2016,642(13):766-772
The synthesis of heterocyclic azo‐dyes via conventional heating and microwave (MW) heating was investigated. From a sequence of reactions starting from cyanoacetic acid, 4‐arylazo‐2H‐pyrazol‐3‐ylamines and 4‐arylazo‐2‐phenyl‐2H‐pyrazol‐3‐ylamines were obtained. The structures these compounds were obtained by inspection of spectroscopic and analytical techniques including 1H and 13C NMR spectroscopy, IR spectroscopy, mass spectrometry, and elemental analysis. The fastness properties and UV/Vis absorption spectroscopic data of these disperse dyes in printing polyester fabrics were investigated. 相似文献
954.
A.B. Nurul Najian E.A.R. Engku Nur Syafirah Nabilah Ismail Maizan Mohamed Chan Yean Yean 《Analytica chimica acta》2016
In recent years extensive numbers of molecular diagnostic methods have been developed to meet the need of point-of-care devices. Efforts have been made towards producing rapid, simple and inexpensive DNA tests, especially in the diagnostics field. We report on the development of a label-based lateral flow dipstick for the rapid and simple detection of multiplex loop-mediated isothermal amplification (m-LAMP) amplicons. A label-based m-LAMP lateral flow dipstick assay was developed for the simultaneous detection of target DNA template and a LAMP internal control. This biosensor operates through a label based system, in which probe-hybridization and the additional incubation step are eliminated. We demonstrated this m-LAMP assay by detecting pathogenic Leptospira, which causes the re-emerging disease Leptospirosis. The lateral flow dipstick was developed to detect of three targets, the LAMP target amplicon, the LAMP internal control amplicon and a chromatography control. Three lines appeared on the dipstick, indicating positive results for all representative pathogenic Leptospira species, whereas two lines appeared, indicating negative results, for other bacterial species. The specificity of this biosensor assay was 100% when it was tested with 13 representative pathogenic Leptospira species, 2 intermediate Leptospira species, 1 non-pathogenic Leptospira species and 28 other bacteria species. This study found that this DNA biosensor was able to detect DNA at concentrations as low as 3.95 × 10−1 genomic equivalent ml−1. An integrated m-LAMP and label-based lateral flow dipstick was successfully developed, promising simple and rapid visual detection in clinical diagnostics and serving as a point-of-care device. 相似文献
955.
Wenshan He Yimin Sun Jiangbo Xi Abduraouf Alamer Mohamed Abdurhman Jinghua Ren Hongwei Duan 《Analytica chimica acta》2016
The increasing demands for portable, wearable, and implantable sensing devices have stimulated growing interest in innovative electrode materials. In this work, we have demonstrated that printing a conductive ink formulated by blending three-dimensional (3D) porous graphene–carbon nanotube (CNT) assembly with ionic liquid (IL) on two-dimensional (2D) graphene paper (GP), leads to a freestanding GP supported graphene–CNT–IL nanocomposite (graphene–CNT–IL/GP). The incorporation of highly conductive CNTs into graphene assembly effectively increases its surface area and improves its electrical and mechanical properties. The graphene–CNT–IL/GP, as freestanding and flexible substrates, allows for efficient loading of PtAu alloy nanoparticles by means of ultrasonic-electrochemical deposition. Owing to the synergistic effect of PtAu alloy nanoparticles, 3D porous graphene–CNT scaffold, IL binder and 2D flexible GP substrate, the resultant lightweight nanohybrid paper electrode exhibits excellent sensing performances in nonenzymatic electrochemical detection of glucose in terms of sensitivity, selectivity, reproducibility and mechanical properties. 相似文献
956.
New Pyrimidine‐2‐thiones from Reactions of Amidrazonethiols with 2‐Amino‐1,1,2‐ethenetricarbonitrile and Investigation of Their Antitumor Activity 下载免费PDF全文
N. A. A. Elkanzi Nesrin M. Morsy Ashraf A. Aly Alan B. Brown Mohamed Ramadan 《Journal of heterocyclic chemistry》2016,53(6):1838-1842
Reactions of thiosemicarbazones with 2‐amino‐1,1,2‐ethenetricarbonitrile were reported. The reaction occurred in the amidrazonyl site, and new pyrimidine‐2‐thiones were obtained. The reaction mechanism was discussed. The structure of products was elucidated by MS, IR, and NMR spectra together with elemental analyses. The antitumor activity was evaluated against one tumor cell line. Using a standard MTT assay, the effect of the samples on the growth of HepG2 cells was investigated. Half of these compounds showed no cytotoxic effect on HepG2 cells, while the others result in decreasing in the HepG2 cell viability. 相似文献
957.
Synthesis and Biological Evaluation of Some Heterocyclic Compounds from Salicylic Acid Hydrazide 下载免费PDF全文
E. M. Sarshira N. M. Hamada Y. M. Moghazi M. M. Abdelrahman 《Journal of heterocyclic chemistry》2016,53(6):1970-1982
Different heterocyclic compounds were prepared starting from 2‐hydroxy benzohydrazide; for example, cyclization of hydrazide hydrazone 3 derived from 2‐hydroxybenzohydrazide 2 with acetic anhydride or concentrated sulfuric acid gave 1,3,4‐oxadiazole derivatives 4 – 5 . On the other hand, direct cyclization of 2‐hydroxy benzohydrazide 2 with one carbon cyclizing agent gave a new derivative of 1,3,4‐oxadiazole 7 , 8 , 9 , 10 , 11 . Heating of hydrazide hydrazone 3 with thioglycolic acid in pyridine gave thiazolidinone 12 . When 2‐hydroxy benzohydrazide 2 reacted with aliphatic carboxylic acids such as formic acid or acetic acid, it gave the corresponding N‐formyl or N‐acetyl derivatives 6 . Subsequent cyclization of 6 using phosphorous pentasulphide in pyridine gave 1,3,4‐thiadiazoles 13 . Cyclization of 2‐hydroxy benzohydrazide with ethyl acetoacetate gives pyrazolone derivative 14 . Finally, when an ethanolic solution of acid hydrazide 2 was treated with ammonium thiocyanate in 35% HCl, it gave the thiosemicarbazide 15 . Subsequent treatment of 15 with concentrated sulfuric acid or 10% sodium hydroxide gave 5‐amino‐1,3,4‐thiadiazole 16 and 1,2,4‐triazole 17 , respectively. The structures of all newly isolated compounds were confirmed using 1H NMR, IR spectra, and elemental analyses. The antimicrobial activities for all isolated compounds were examined against different microorganisms. 相似文献
958.
Hanafi H. Zoorob Mohamed S. Elsherbini Wafaa S. Hamama 《Journal of heterocyclic chemistry》2016,53(3):941-944
2‐Bromocyclododecanone was utilized as precursor to synthesize polyfused heterocyclic cyclododecane ring systems. Transformation of 2‐bromocyclododecanone ( 5 ) with 1H‐benzimidazole‐2‐thiole ( 6 ), benzo[d]thiazole‐2‐thiol ( 9 ), 2‐naphthol ( 12 ), and thiophenol ( 15 ) afforded thiazolo[2,3‐b]benzimidazole ( 8 ), thiazolo[2,3‐b]benzothaizole derivative ( 11 ) naphtho[1,2‐d]furan derivative ( 14 ) and 2‐(phenylthio)cyclododecanone ( 16 ), respectively. 相似文献
959.
Let Γ be a graph with the doubling property for the volume of balls and P a reversible random walk on Γ. We introduce H1 Hardy spaces of functions and 1-forms adapted to P and prove various characterizations of these spaces. We also characterize the dual space of H1 as a BMO-type space adapted to P. As an application, we establish H1 and H1- L1 boundedness of the Riesz transform. 相似文献
960.