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1.
This review is a broad overview of the chemistry of 2-tosylacetonitrile, which considered as a very reactive synthetic compound. The synthetic methods are reported. The reactions of the title compound lead to the preparation of a variety of heterocyclic ring systems, such as five- and six-membered ring systems containing one, two, or three heteroatoms. The reaction mechanisms are discussed. 相似文献
2.
Zidan Mohamed M. Houmani Amran Ab. Majid Shahidan Radiman Zaharudin Ahmad 《Journal of Radioanalytical and Nuclear Chemistry》2010,285(2):271-277
226Ra is a member of the 238U natural decay series and is one of the most important isotope to be determined among the naturally occurring nuclides in
environmental samples. In order to evaluate the radiation dose from 226Ra, it is important to know its mobility in different types of soils. The aim of the present study is to quantify the influence
of physico-chemical soil properties on 226Ra adsorption. The distribution coefficients (K
d-value) of 226Ra in Selangor soil series samples were measured in one core, at three depth levels to evaluate the adsorbability of 226Ra. The soil samples were spiked with 226Ra tracer and the activities of 226Ra in the separated phase from batch sorption test were measured by a low background but high efficiency well-type HPGe detector.
Several physico-chemical soil properties were also characterised for each soil samples. Pearson’s correlation and stepwise
multiple regression test were applied at the 0.05 level of significance throughout all analysis to determine the relationships
and influences between distribution coefficients (K
d-value) of 226Ra with physicochemical soil properties for the Selangor soil series. The observed K
d value was in the range of 50.55–172.28 mL g−1 (mean: 93.20 ± 46.99 mL g−1). The regression showed that the highest positive correlations were observed for organic matter (OM) and cation exchange
capacity (CEC) (r = 0.96**, 0.81**, respectively) with K
d-values. The results indicate that the stepwise multiple regression model incorporating the soil’s OM and CEC accounts for
98% of the variability in distribution coefficients of 226Ra. 相似文献
3.
Ahmed A. Fadda Nesma M. Bayoumy Nanees N. Soliman Doaa M. Eldiasty 《Journal of heterocyclic chemistry》2019,56(2):597-607
Innovative poly‐substituted heterocyclic rings incorporating dioxoisoindoline ( 2 – 25 ) were synthesized through the reaction of dioxoisoindoline derivative 2 as starting compound with various types of reagents. All compounds were characterized by appropriate means of (1H‐NMR, 13C‐NMR, IR, and mass). The prepared compounds were evaluated as antimicrobial agents against Escherichia coli, Staphylococcus aureus, and Candida albicans microorganisms. The tested compounds exhibited low to moderate antibacterial activities and promising results as antifungal agents. 相似文献
4.
Chafika Bougheloum Sabrina Alioua Robila Belghiche Nesma Benali Abdelrani Messalhi 《Journal of heterocyclic chemistry》2020,57(1):120-131
An efficient and convenient protocol for the one-pot synthesis of new benzothiazoles bearing sulfonamide or cyclic imide moieties using Cesium salt of Wells-Dawson heteropolyacid (Cs5HP2W18O62) as solid catalyst and water as solvent under ultrasound irradiation was reported. The reaction speed was remarkably catalyzed with the aid of ultrasound irradiation. Moreover, this approach prepares multiple other benefits such as operational ease, higher yields, and energy performance. 相似文献
5.
Nesma A. Abd El-Fatah Ahmed F. Darweesh Adel A. Mohamed Ismail A. Abdelhamid Ahmed H.M. Elwahy 《Tetrahedron》2017,73(11):1436-1450
The synthetic utility of 2-mercaptonicotinonitriles 3 and 4, as well as 2-mercapto-4-oxo-6-phenyl-1,4-dihydropyrimidine-5-carbonitrile 20 as building blocks for novel bis- and poly(pyridines), along with poly(pyrimidines) via alkylation with the corresponding bis- and poy(halo) compounds was investigated. Spectroscopic and theoretical studies confirmed the S-alkylation rather than the N-alkylation. 相似文献
6.
Five homologous series of the four-ring 4-substituted phenylazo phenyl 4?-(4?-alkoxy phenylazo) benzoates (Ina–e) were prepared and their mesophase behaviour investigated by differential scanning calorimetry (DSC) and phases identified by polarised light microscopy (PLM). Compounds prepared were structurally characterised via infrared, 1H-NMR, mass spectroscopy, thermogravimetric and elemental analysis. Transition temperatures were first correlated with the alkoxy-chain length (n, that varies between 6, 8, 10, 14, and 16 carbons) within each homologous series, and again with the polarisability anisotropy (ΔαX) of the Ar-X bond, where X changes between CH3O, CH3, H, Br, and CN groups . Comparative studies were made to investigate the effect of introducing the extra phenyl azo moiety into the previously investigated three-ring compounds, 4-substituted phenyl 4′-(4″-alkoxyphenylazo) benzoates (IIna–e), 4-substituted phenylazo 4′-(4″- alkoxy phenyl) benzoates (IIIna–e), and 4-(4′-alkoxy phenylazo) phenyl 4″-substituted benzoates (IVna–e), each bear the same polar group, X, and the alkoxy group, n . 相似文献
7.
Sabrina Alioua Chafika Bougheloum Nesma Benali Abdelrani Messalhi 《Journal of heterocyclic chemistry》2020,57(1):281-290
A simple and efficient preparation of novel series of mono- and bis-pyrrolidine-2,5-diones containing sulfonamide moiety was described. The strategy involved sequential one-pot sulfonylation-nucleophilic substitution procedure and was found effective under ultrasound activation and used for the first time. This approach allows the synthesis of products in good to excellent yields in short reaction time. 相似文献
8.
Ahmed A. Fadda Nanees N. Soliman Nesma M. Bayoumy 《Journal of heterocyclic chemistry》2019,56(9):2369-2378
We report herein the interaction of diethylethoxymethylene malonate ( 1 ) with 2‐cyanomethylbenzothiazole ( 7 ) to give diethyl 2‐(2‐benzothiazole‐2‐(3H)‐ylidiene)‐2‐(cyano ethyl) malonate ( 8a ) in excellent yield. Ethyl 4‐cyano‐1‐oxo‐1H‐benzo[4,5]thiazolo[3,2‐a]pyridine‐2‐carboxylate (9) was synthesized from 8a and subjected to react with hydrazine hydrate to give its corresponding acid hydrazide 10 . Condensation of 10 with different acid anhydrides afforded the corresponding benzothiazolo pyridine carboxamide derivatives 11 – 15 . In addition, we report a simple synthesis of N′‐(benzo[d]thiazol‐2‐yl)‐2‐((4‐ayl)amino)acetohydrazide derivative ( 17 ), which then reacted with different amines to give the corresponding acetohydrazide derivatives 19a – c . Moreover, compound 17 reacted with some sulfonamide derivatives to give the corresponding sulfonamide derivatives 20 and 22a , b .The newly synthesized compounds were established their structures on the bases of their correct analytical and spectral data and evaluated their antimicrobial activity. It was found that compounds 22a , b displayed the highest antimicrobial activity against the tested organisms. 相似文献
9.
Nanees N. Soliman Yasmin M. Tag Nesma M. Bayoumy 《Journal of heterocyclic chemistry》2021,58(5):1141-1153
Bis enaminone derivative 6 was reactive enaminone to synthesize new heterocyclic compounds containing diazipine, pyrazolopyrimidine, triazolopyrimidine, and pyrazole moieties by reaction with different bifunctional reagents. Structures of new compounds were confirmed by analytical and spectral data. Moreover, the new compounds were screened in-vitro as antitumor agents for Ehrlich ascites at different concentration. The results showed the compounds 18 , 19, and 20a have a good activity. In addition to, the molecular docking of these mentioned compounds was studied using vascular endothelial growth factor receptor. 相似文献
10.
Majd Abazid Nesma Houmani Jerome Boudy Bernadette Dorizzi Jean Mariani Kiyoka Kinugawa 《Entropy (Basel, Switzerland)》2021,23(11)
This work addresses brain network analysis considering different clinical severity stages of cognitive dysfunction, based on resting-state electroencephalography (EEG). We use a cohort acquired in real-life clinical conditions, which contains EEG data of subjective cognitive impairment (SCI) patients, mild cognitive impairment (MCI) patients, and Alzheimer’s disease (AD) patients. We propose to exploit an epoch-based entropy measure to quantify the connectivity links in the networks. This entropy measure relies on a refined statistical modeling of EEG signals with Hidden Markov Models, which allow a better estimation of the spatiotemporal characteristics of EEG signals. We also propose to conduct a comparative study by considering three other measures largely used in the literature: phase lag index, coherence, and mutual information. We calculated such measures at different frequency bands and computed different local graph parameters considering different proportional threshold values for a binary network analysis. After applying a feature selection procedure to determine the most relevant features for classification performance with a linear Support Vector Machine algorithm, our study demonstrates the effectiveness of the statistical entropy measure for analyzing the brain network in patients with different stages of cognitive dysfunction. 相似文献