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81.
Wael A. El-Sayed Fahad M. Alminderej Marwa M. Mounier Eman S. Nossier Sayed M. Saleh Asmaa F. Kassem 《Molecules (Basel, Switzerland)》2022,27(7)
This study represents the design and synthesis of a new set of triazole-coumarin-glycosyl hybrids and their tetrazole hybrid analogues possessing various sugar moieties and modified analogues. All the newly synthesized derivatives were screened for their cytotoxic activities against a panel of human cancer cell lines. The coumarin derivatives 10, 13 and 15 derivatives revealed potent cytotoxic activities against Paca-2, Mel-501, PC-3 and A-375 cancer cell lines. These promising analogues were further examined for their inhibitory assessment against EGFR, VEGFR-2 and CDK-2/cyclin A2 kinases. The coumarin-tetrazole 10 displayed broad superior inhibitory activity against all screened enzymes compared with the reference drugs, erlotinib, sorafenib and roscovitine, respectively. The impact of coumarin-tetrazole 10 upon cell cycle and apoptosis induction was determined to detect its mechanism of action. Additionally, it upregulated the levels of casp-3, casp-7 and cytochrome-c proteins and downregulated the PD-1 level. Finally, molecular docking study was simulated to afford better rationalization and gain insight into the binding affinity between the promising derivatives and their targeted enzymes, which could be used as an optimum lead for further modification in the anticancer field. 相似文献
82.
Cover Picture: Selective Catalytic Synthesis Using the Combination of Carbon Dioxide and Hydrogen: Catalytic Chess at the Interface of Energy and Chemistry (Angew. Chem. Int. Ed. 26/2016)
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84.
Asmaa F. Kassem Eman M.H. Abbas Nadia T. Al-Qurashi Thoraya A. Farghaly 《Journal of heterocyclic chemistry》2020,57(2):611-620
With aiding of microwave radiation, new series of fused-thiazolopyrimidines and fused-triazolopyrimidines each with cycloheptane have been synthesized through the reaction of cycloheptane-thione with α-haloketones or hydrazonoyl chlorides in short-time intervals as well as high yield. Moreover, reaction of 2,7-bis(2-chlorobenzylidene)cycloheptan-1-one with o-aminothiophenol and heterocyclic amines afforded benzo[b]cyclohepta[e][1,4]thiazepine derivative and cycloheptapyrimidines fused with different azoles, respectively. The structure for all products was discussed and proved based on the results of spectral data and elemental analysis. Evaluation of the antimicrobial activity of selected products indicated that most of derivatives showed their potent activity exceeds the reference antibiotic in some cases. 相似文献
85.
Abstract The change in electrical properties of TGS crystals due to induced defects created by fast neutron irradiation of two different energies (2 and 14 MeV) and different integrated neutron fluxes have been studied in the vicinity of phase transition. It is observed that the electrical conductivity increases with increase of neutron fluence up to 1.7 × 1010 n · cm?2 and the values of the relative change of electrical conductivity in case of 2 MeV are higher than that of 14 MeV neutrons at the same neutron fluence (φ) 相似文献
86.
Measurements of the specific heat were carried out on deuterated trigylcine selenate (DTGSe) single crystals to clarify its critical nature near the ferroelectric transition point (Tc ). The results obtained have indicated that DTGSe crystals deuterated by 90% exhibit a first-order phase transition. This paper presents also the electrical conductivity (δ) of DTGSe crystals. The deuterium substitution induces an increase in the Curie point Tc , and a decrease in the conductivity in the para- and ferroelectric phases accompanied by an increase in the activation energy (W) in both phases. 相似文献
87.
A. M. Hussein A. A. Kassem M. ElGarhy E. Abdullah 《Isotopes in environmental and health studies》2013,49(8):327-330
The tissue distribution of colloidal zirconyl phosphate-P32 and its retention following i.m and i.v. injection in mice were studied. About 63 per cent of the i.m. injected P32 activity was retained at the site of injection after 5 days, suggesting the use of the colloid in the local treatment of tumours. The deposition of the colloid in bone and liver after i.v. injection presented zirconyl phosphateP32 as useful in the radiotherapy of bone and liver disease. 相似文献
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89.
Abstract A study has been made of the temperature dependence of the d.c. conductivity of pure and borated low density polyethylene LDPE (4% and 8% borax). The above calculations were carried out before and after X-ray irradiation. The irradiation dose was varied from 0 to 1000 rad. The d.c. electrical conductivity of Polyvinyl chloride (PVC) and perspex was measured as a function of temperature ranging from 20°C to 100°C. These samples were irradiated with X-rays of dose 200 rad. The variation of the d.c. conductivity of the treated samples versus temperature was investigated. The results reveal that the d.c. conductivity of LDPE is highly affected by radiation and/or dopant. In addition, the sensitivity of the explored polymers to X-ray irradiation is strongly dependent on its chemical nature. 相似文献
90.