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11.
12.
Etify A. Bakhite Abdu E. Abdel-Rahman Omima. S. Mohamed Eman A. Thabet 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):1983-2006
(4-Aryl-3-cyano-6-(2-thienyl)pyridin-2-ylthio)acethydrazides (5a–c), 3-amino-4-aryl-6-(2-thienyl)thieno[2,3-b]pyridine-2-carbohydrazides (6a–c) and 3-amino-4-phenyl-6-(2-thienyl)thieno[2,3-b]pyridine-2-carboxylic acid (30) were prepared and employed as key intermediates in the synthesis of the title compounds. 相似文献
13.
A. A. Fadda S. B. Bondock A. M. Khalil Eman H. Tawfik 《Journal of heterocyclic chemistry》2013,50(4):838-843
The starting N‐(2‐pyridyl)‐6‐methyl‐4‐phenyl‐2‐thioxo‐1,2,3,4‐tetrahydropyrimidine‐5‐carboxamide ( 4 ) was used as a key intermediate for the synthesis of new 1,2,3,4‐tetrahydropyrimidine‐2‐thione and their thiazolo[3,2‐a]pyrimidine, thiazino and benzothiazipen derivatives. The reaction of 4 with haloketones in ethanol catalyzed by base afforded the corresponding thiophenopyrimidine and pyrimidothiazipine derivatives 5 , 6 , 7 , 8 , 9 , 10 . Methylation and formylation of 4 led to the pyrimidine derivatives 15 and 16 , respectively. The preventative compounds were established on the basis of elemental and spectral data. 相似文献
14.
The novel 2-(1H)-pyridone, the lead compound of the pyridone derivative 1, reacted with an electrophilic reagent (ethyl chloroacetate) to give the corresponding ester 2. Condensation of compound 2 with thiosemicarbazide and/or hydrazine hydrate afforded the mercaptotriazole and the corresponding acetic acid hydrazide derivatives 3 and 4, respectively. The latter compound reacted with ethyl acetoacetate, ethyl cyanoacetate, and maleic anhydride to give compounds 5, 6, and 7, respectively. Alkylation of compound 3 with methyl iodide or chloroacetic acid afforded methylsulfanyltriazole and thiazolotriazole derivatives 8 and 9, respectively. Compound 8 reacted with glycine to afford the imidazotriazole derivative 10. Both compounds 9 and 10 reacted with glucose and benzaldehyde to give compounds 11, 12, 13, and 14, respectively. Some of the prepared products were selected and subjected to screening for their antioxidant activity. 相似文献
15.
以氨三乙酸HNTA2-为主要配体,缬氨酸(valine)或亮氨酸(leucine)为次要配体在微酸性介质中合成了Ni(Ⅱ),Cu(Ⅱ),and Zn(Ⅱ)的三元配合物。用元素分析、热分析、FTIR,UV-Vis分光光度法,磁性测量和质谱法表征了合成的三元配合物。结果表明,三元配合物可在金属(M):氨三乙酸(HNTA)∶缬氨酸(valine)或亮氨酸(leucine)=1∶1∶1时制得,其分子结构为[M(HNTA)(valine)(H2O)2].1.5H2O and[M(HNTA)(leucine)(H2O)2].1.5H2O(其中M=Ni(Ⅱ)or Cu(Ⅱ))和H2[Zn(NTA)(valine)(H2O)]H2O。标题三元过渡金属配合物为八面体对称构型。同时研究了该三元配合物对大肠杆菌,金黄色葡萄球菌,白色念珠菌,黄曲霉菌(菌株从开罗大学理学院微分析中心获得)的抗菌活性。根据推荐的知名方法用标准的抗菌和抗真菌剂进行体外测试(in vitro)以评估我们的新制备的配合物对细菌和真菌物种的生长抑制活性。 相似文献
16.
Eman M. Othman Amany A. Bekhit Mohamed A. Anany Thomas Dandekar Hanan M. Ragab Ahmed Wahid 《Molecules (Basel, Switzerland)》2021,26(10)
The present study reports the synthesis of new purine bioisosteres comprising a pyrazolo[3,4-d]pyrimidine scaffold linked to mono-, di-, and trimethoxy benzylidene moieties through hydrazine linkages. First, in silico docking experiments of the synthesized compounds against Bax, Bcl-2, Caspase-3, Ki67, p21, and p53 were performed in a trial to rationalize the observed cytotoxic activity for the tested compounds. The anticancer activity of these compounds was evaluated in vitro against Caco-2, A549, HT1080, and Hela cell lines. Results revealed that two (5 and 7) of the three synthesized compounds (5, 6, and 7) showed high cytotoxic activity against all tested cell lines with IC50 values in the micro molar concentration. Our in vitro results show that there is no significant apoptotic effect for the treatment with the experimental compounds on the viability of cells against A549 cells. Ki67 expression was found to decrease significantly following the treatment of cells with the most promising candidate: drug 7. The overall results indicate that these pyrazolopyrimidine derivatives possess anticancer activity at varying doses. The suggested mechanism of action involves the inhibition of the proliferation of cancer cells. 相似文献
17.
Eman M. Moaaz Amr M. Mahmoud Ahmed S. Fayed Mamdouh R. Rezk Ezzat M. Abdel-Moety 《Electroanalysis》2021,33(8):1895-1901
Antibiotics determination plays a major role in minimizing antimicrobial resistance starting from quality control of pharmaceutical formulations to therapeutic drug monitoring. Green modified glassy carbon electrode has been developed for determination of tedizolid phosphate; new antibiotic prodrug; in presence of its active metabolite. The graphene transducer interlayer, dispersed with PVC, improved the electrode stability and standard potential reproducibility. Graphene hydrophobicity prevented the water layer formation between the sensing layers that decreased the potential drift down to 267 μV h−1. Electrochemical impedance showed a low resistance value for graphene containing sensor due to its high electron transfer ability. 相似文献
18.
Eman A. E. El-Helw Alaa R. I. Morsy Ahmed I. Hashem 《Journal of heterocyclic chemistry》2021,58(4):1003-1014
The hydrazide obtained from furan-2(3H)-one integrated with a quinolin-2(1H)-one core reported previously by our research group was utilized as a building block synthon to obtain some pyrrolone, pyridazinone, oxadiazole, and triazole derivatives through treating with some carbon electrophilic reagents, for example, chloroacetyl chloride, benzoyl chloride, acetic anhydride, carbon disulfide, 3,4-dimethoxybenzaldehyde, and 2-oxoquinolin-3-carbaldehyde to achieve the target heterocycles. The newly synthesized compounds were evaluated as immunomodulator against highly pathogenic avian influenza virus (H5N8). The compounds 1 , 11 , and 17 displayed the highest potency (100% protection). 相似文献
19.
Inside Back Cover: In Situ Synthesis of Self‐Assembled Gold Nanoparticles on Glass or Silicon Substrates through Reactive Inkjet Printing (Angew. Chem. Int. Ed. 2/2014) 下载免费PDF全文
20.
Malak Azmat Ali G. Murtaza Afzal Khan Eman Algrafy Asif Mahmood Shahid M. Ramay 《International journal of quantum chemistry》2020,120(19):e26357
Highly spin-polarized ferromagnetic materials are essential for efficient spintronic devices. Here, 100% spin-polarized compounds Rb2TaZ6 (Z = Cl, Br) studied via density functional theory are reported. These compounds show stability in the ferromagnetic phase with cubic symmetry and half metallic behavior, thereby exhibiting a nonzero direct band gap in the spin-down channel and zero band gap in the spin-up configuration. The Ta-d sates contribute mainly to the net magnetic moments as explained by the crystal field theory and density of states. High Curie temperatures of 960.35 and 1021.74 K for Ra2TaCl6 and Rb2TaBr6, along with maximum spin polarizability, make these compounds favorable for efficient spintronic applications. 相似文献