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71.
Sadeq M. Al-Hazmy Mohamed Oussama Zouaghi Jamal N. Al-Johani Youssef Arfaoui Rania Al-Ashwal Bechir Hammami Ibrahim A. Alhagri Nabil A. Alhemiary Naceur Hamdi 《Molecules (Basel, Switzerland)》2022,27(18)
In this work, a three-component reaction of 3-acetyl-4-hydroxycoumarine, malononitrile, or cyanoacetate in the presence of ammonium acetate was used to form coumarin derivatives. The chemical structures of new compounds were identified by 1H, 13C NMR and an elemental analysis. These compounds were examined in vitro for their antimicrobial activity against a panel of bacterial strains. In addition, these compounds were investigated for antioxidant activities by superoxideradical, DPPH (2,2-Diphenyl-1-picrylhydrazyl), and hydroxyl radical scavenging assays, in which most of them displayed significant antioxidant activities. Furthermore, these compounds were evaluated for anti-inflammatory activity by indirect hemolytic and lipoxygenase inhibition assays and revealed good activity. In addition, screening of the selected compounds 2–4 against colon carcinoma cell lines (HCT-116) and hepatocellular carcinoma cell lines (HepG-2) showed that that 2-amino-4-hydroxy-6-(4-hydroxy-2-oxo-2H-chromen-3-yl)nicotinonitrile 4 exhibited good cytotoxic activity against standard Vinblastine, while the other compounds exhibited moderate cytotoxic activity. Docking simulation showed that2-amino-4-hydroxy-6-(4-hydroxy-2-oxo-2H-chromen-3-yl)nicotinonitrile 4 is an effective inhibitor of the tumor protein HCT-116. A large fluorescence enhancement in a highly acidic medium was observed, and large fluorescence quenching by the addition of traces of Cu2+ and Ni2+ was also remarked. 相似文献
72.
Abeer S. Alqurashi Luluah M. Al Masoudi Hamida Hamdi Abeer Abu Zaid 《Molecules (Basel, Switzerland)》2022,27(17)
Opuntia ficus-indica (OFI) is a cactus that is widely cultivated in the Kingdom of Saudi Arabia especially in the Taif region due to its favorable weather for growing, and it has benefits as a food and traditional medicine. The aim of the current study was to chemically characterize Opuntia ficus-indica seed oil from Taif, Kingdom of Saudi Arabia, using GC-MS and HPLC analysis and evaluate its antioxidant, antiviral, antifungal, antibacterial and anticancer activities. Linolenic acid was the dominating fatty acid in OFI oil, followed by oleic acid, linoleic acid, palmitic acid and stearic acid. Total tocopherol (α-, β-, Ɣ-tocopherol) was found to be 24.02 μg/mL. Campesterol was the main phytosterol, followed by γ- & β -sitosterol, and Stigmasterol. The phenolic components scored 30.5 mg gallic acid equivalent per ml of oil with 89.2% antioxidant activity (% DPPH radical inhibition) at 200 µL/mL of OFI oil. OFI oil showed an inhibition efficacy against microbial strains especially Saccharomyces cervisiae with a diameter (28.3 ± 0.4), MBC (15 µg/mL) and MIC bacteriostatic (10 µg/mL). While OFI oil had no effect against Aspergillus niger, OFI oil showed weak inhibitory activity against A-2780 (Ovarian carcinoma) cell line, although it showed significant inhibitory activity against PC-3 (Prostate carcinoma) cell line. OFI oil exhibited an antiviral effect (22.67 ± 2.79%) at 300 µg/mL of Oil against herpes simplex type 2 (HSV-2) virus. The bioactive compounds of OFI oil, as well as its main biological activities, make it a promising candidate for the non-communicable disease management. 相似文献
73.
A novel quadridentate, N2O2 type Schiff base, synthesized from 1,4‐bis‐(o‐aminophenoxy)butane and 2‐hydroxynaphthalin‐1‐carbaldehyde, forms stable complexes with transition metal ions such as Co(II), Cu(II) and Ni(II) in DMF. Microanalytical data, elemental analysis, magnetic measurements, UV‐visible and IR‐spectra as well as conductance measurements were used to confirm the structures. Electrochemical measurements show that metal complexes undergo quasi‐reversible one‐electron redox processes. The voltammetric results also revealed that the CuL complex has the highest electron transfer rate indicating that both the Cu(II) and Cu(I) forms appear in a similar planar configuration, so the electron transfer does not require larger reorganization of the complex. 相似文献
74.
H. Hamdi R. Abderrahim F. Meganem 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(1):32-36
Formation of inclusion complex between benzidine diammonium dipicrate and β-cyclodextrin with stoichiometry 1:2 (guest–host) has been established by UV, 1H NMR, 13C NMR, IR spectra and powder X-ray diffractometry. 1H NMR studies are used to confirm the inclusion and to provide information on the geometry of dipicrate inside the cavity of β-cyclodextrin. 相似文献
75.
This paper presents a unified analytical method for efficient computation of first and second order statistics of the signal-to-interference-plus-noise-ratio (SINR) in wireless communication systems. New exact expressions are derived for the moments of SINR and its autocorrelation function that are valid for arbitrary interfering signals. These are used to examine the accuracy of the commonly used approximations for the average SINR and to investigate effects of fast fading and interfering signals' temporal behavior on the autocorrelation properties of SINR. 相似文献
76.
Tarek Hamdi 《Complex Analysis and Operator Theory》2018,12(7):1697-1705
The present paper provides a proof of \(i^*(\mathbb {C}P+\mathbb {C}(I-P); \mathbb {C}Q+\mathbb {C}(I-Q))=-\chi _{{ orb}}(P,Q)\) for two projections P, Q without any extra assumptions. An analytic approach is adopted to the proof, based on a subordination result for the liberation process of symmetries associated with P, Q. 相似文献
77.
Naceur Hamdi Feten Bouabdallah Antonio Romerosa Rached Benhassen 《Comptes Rendus Chimie》2010,13(10):1261-1268
A new family of coumarin derivatives (4a–i) containing a chalcone moiety was synthesized by condensation of 3-acetyl-4-difluoro boryloxycoumarin (2) with aryl and heteroaryl aldehydes with piperidine in chloroform. Resulting compounds were characterized by IR, 13C, 1H NMR and UV visible spectroscopy. Compound 3-((2E)-3-(3,4,5-Trimethoxy-phenyl)prop-2-enoyl)-2(H)-chromen-2-one (4g) was characterized by single crystal X-ray diffraction. The antioxidant and antibacterial activities of the obtained compounds 4a-i was evaluated. The biological activity found for these compounds is discussed against their structural features, physical and chemical properties. 相似文献
78.
Hamdi Ben Yahia Ute Ch. Rodewald Rainer P?ttgen 《Monatshefte für Chemie / Chemical Monthly》2010,37(12):495-499
Abstract
The titanyl arsenate NaTiO[AsO4] was synthesized in the form of colourless lath-shaped crystals from arsenic and titanium dioxide in a NaCl/KCl flux at 850 °C. NaTiO[AsO4] crystallizes with the monoclinic low-temperature form LT-CaTiO[SiO4], space group P21/c. The structure was refined from single crystal diffractometer data: a = 6.7170(9), b = 8.7707(12), c = 7.2447(10) ?, β = 114.77(1)°, wR2 = 0.0559, 789 F 2 values, and 74 variables. NaTiO[AsO4] is characterized by a topology common to a wide range of oxide structures of stoichiometry AMOXO4. It consists of parallel chains of trans-corner-sharing TiO6 octahedra, cross-linked by isolated AsO4 tetrahedra. 相似文献79.
Miscible gas injection is one of the most effective enhanced oil recovery techniques. There are several challenges in accurately modeling this process, which occurs in the near-miscible region. The adjustment of relative permeability for near-miscible processes is the main focus of this work. The dependence of relative permeability on phase identification can lead to significant complications while simulating near-miscible displacements. We present an analysis of how existing methods incorporate compositional dependence in relative permeability functions. The sensitivity of the different methods to the choice of reference points is presented with guidelines to limit the modification of the relative permeabilities to physically reasonable values. We distinguish between the two objectives of reflecting near-miscible behavior and ensuring smooth transitions across phase changes. We highlight an important link that combines the two objectives in a more general framework. We make use of Gibbs free energy as a compositional indicator in the generalized framework. The new approach was implemented in an automatic differentiation general purpose research simulator and tested on a set of near-miscible gas-injection problems. We show that including compositional dependencies in the relative permeability near the critical point impacts the simulation results with significant improvements in nonlinear convergence. 相似文献
80.
Zibi Wang Ding Wang Dong Liu Xiang Han Xiaoxu Liu Hamdi Torun Zhanhu Guo Sidi Duan Ximin He Xuehua Zhang Ben Bin Xu Fei Chen 《Advanced functional materials》2023,33(29):2301117
A seamless and tough interface to integrate incompatible/immiscible soft materials is highly desired for flexible/wearable electronics and many soft devices with multi-layer structures. Here, a surfactant-mediated interfacial chemistry is introduced to achieve seamless and tough interfaces in soft multi-layer structures, with an ultra-high interfacial toughness up to ≈1300 J m−2 for the architectural gel hybrid (AGH). The reversible noncovalent interfacial interactions efficiently dissipate energy at the interface, thereby providing excellent durability. The interfacial toughness only decreases by ≈6.9% after 10 000 tensile cycles. This strategy can be universally applied to hybrid systems with various interfaces between an interior hydrogel (PAA, PVA, PAAm, and gelatin) and an exterior hydrophobic soft matter (ionogel, lipogel and elastomer). The AGH-based mechano-sensor presents high robustness and stability in a wide range of conditions, including open air, underwater, and various solvents and temperatures. Epidermal bio-monitoring, tactile trajectory, and facial expression recognition are demonstrated using the AGH sensors in various environments. A rich set of electrophysiological signals of high quality are acquired. 相似文献