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71.
Mohamed M. Abdalla Bakr F. Abdel-Wahab Abdel-Galil E. Amr 《Monatshefte für Chemie / Chemical Monthly》2009,60(1):129-137
Abstract
N-(p-substituted phenyl)-4-cyanopyrrolidin-3-ones and their corresponding hydrazines were prepared and used as starting materials
to synthesize heterocyclic candidates as serotonin antagonist and antianexity agents. Condensation of hydrazines with selected
aromatic aldehydes afforded the corresponding Schiff bases. The hydrazines were treated with phenyl isothiocyanate to afford
the corresponding thiosemicarbazides, which were cyclized with ethyl bromoacetate to N-phenylthiazolidinones. The hydrazine was reacted with 1,2,4,5-tetrachlorophthalic anhydride to give the tetrachloroimide
derivative. It was reacted with benzoyl acetonitrile, 2-(bismethylsulfanyl-methylene)malononitrile, 2-ethoxymethylenemalononitrile,
or 2-cyano-3-ethoxyacrylic acid ethyl ester to afford the corresponding pyrazoline derivatives. Schiff bases were obtained
by simple condensation of the hydrazine with different carbonyl compounds. All the compounds were screened for their serotonin
antagonistic and antianexity activities, and they showed high activities compared to buspirone and diazepam as controls.
Graphical abstract
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72.
Walid Ibrahim Hesham El-Sayed Amr El-Chouemie Hoda Amer 《European Journal of Operational Research》2009,199(3):630-639
The increasing complexity of today’s system-on-a-chip designs is putting more pressure on the already stressed design verification process. The verification plan must cover several individual cores as well as the overall chip design. Conditions to be verified are identified by the system’s architects, the designers, and the verification team. Testing for these conditions is a must for the design to tape out, especially for high priority conditions. A significant bottleneck in the verification process of such designs is that not enough time is usually given to the final coverage phase, which makes computing cycles very precious. Thus, intelligent selection of test vectors that achieve the best coverage using the minimum number of computing cycles is crucial for on time tape out. This paper presents a novel heuristic algorithm for test vectors selection. The algorithm attempts to achieve the best coverage level while minimizing the required number of computing cycles. 相似文献
73.
Amr L. Saber 《Talanta》2009,78(1):295-299
An instrumental setup including on-line solid phased extraction coupled to capillary liquid chromatography-electrospray ionization-mass spectrometry (SPE-capLC-ESI-MS) has been constructed to improve the sensitivity for quantification of fluoxetine hydrochloride in human plasma. Prior to injection, 0.5 mL of plasma spiked with metronidazole (internal standard) was mixed with ammonium formate buffer for effective chloroform liquid-liquid extraction. The method was validated in the range 5-60 ng mL−1 fluoxetine, yielding a correlation coefficient of 0.999 (r2). The within-assay and between-assay precisions were between (8.5 and 11%) and (6.6 and 7.5%), respectively. The method was used to determine the amount of fluoxetine in a healthy male 14 h after an intake of one capsule of the antidepressant and anorectic Flutin®, which contains 20 mg fluoxetine per each capsule. Fluoxetine was detected, and the concentration was calculated to 9.0 ng mL−1 plasma. In the preliminary experiments, conventional LC-UV instrumentation was employed. However, it was found that employing a capillary column with an inner diameter of (0.3 mm I.D. × 50 mm, Zorbax C18) increased the sensitivity by a factor of ∼100, when injecting the same mass of analyte. Incorporating an easily automated C18 reversed phase column switching system with SPE (1.0 mm I.D. × 5.0 mm, 5 μm) made it possible to inject up to 100 μL of solution, and the total analysis time was 5.5 min. 相似文献
74.
Amr M. Abdelmoniem Said A. S. Ghozlan Hassan M. Abdelwahab Ismail A. Abdelhamid 《Journal of heterocyclic chemistry》2019,56(9):2637-2643
A novel series of interesting 6,8‐dicyanopyrido[1,2‐a]thieno[3,2‐e]pyrimidine‐2‐carboxylate compounds were prepared via the reaction of readily accessible 2‐cyano‐N‐(thiophen‐2‐yl)acetamide with arylidene malononitriles in pyridine in the presence of piperidine. Biological screening of the tested compounds as antibacterial agents was also studied. 相似文献
75.
Easily attainable new approach to mass yield ferrocenyl Schiff base and different metal complexes of ferrocenyl Schiff base through convenient ultrasonication‐solvothermal method
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Ahmed Mourtada Elseman Ahmed Esmail Shalan Mohamed M. Rashad Ali M. Hassan Nabila M. Ibrahim Amr M. Nassar 《Journal of Physical Organic Chemistry》2017,30(6)
A new alternative approach with crucial mass yield and high reaction rates is proposed for the synthesis of ferrocenyl Schiff bases using an ultrasonication‐solvothermal method. Equimolar condensation of ferrocenecarboxaldehyde and 2‐aminophenol interact with each other, giving 1‐(1‐[2‐hydroxyphenyl‐2‐imino]methyl)‐ferrocene (FcOH). Furthermore, this ligand forms 1:1 complexes with cobalt(II), nickel(II), copper(II), and palladium(II) ions. From the different spectral data, it is found that metal ions coordinate with ligands through the azomethine group and the deprotonated oxygen of the phenol groups. Moreover, FcOH and their complexes were characterized by elemental analysis, Fourier transform infrared, 1H nuclear magnetic resonance, and UV‐visible spectrophotometry. The spectral data of FcOH and its metal complexes were discussed in connection with the structural changes due to complexation. Meanwhile, the information about geometric structures can be concluded from the electronic spectra and the magnetic moments. Plainly, electron spin resonance spectra of the Cu(II) complex revealed dx2?y2 as a ground state, suggesting a square planar geometry around the Cu(II) center. The direct optical band gap energy Eg values of cobalt, nickel, copper, and palladium complexes of FcOH are found to be 3.7, 3.9, 4.6, and 3.65 eV, respectively. 1‐(1‐[2‐Hydroxyphenyl‐2‐imino]methyl)‐ferrocene and its metal complexes were screened for antibacterial activity. The results depict that the metal complexes were found to be more strongly antibacterial than the guardian Schiff base ligand (FcOH) against one or more bacterial species. The minimum inhibitory concentrations of antimicrobial properties of the purified compound were determined using the broth microdilution method. 相似文献
76.
In this work, the commercial polyvinylpyrrolidone (PVP)-capped silver nanospheres (Ag-NSP) were surface decorated with chlorhexidine gluconate (CHXg) for potentiating the antibacterial properties of Ag-NSP. Different formulations of CHXg-loaded Ag-NSP (Ag-NSP/CHXg) were prepared by varying the incubation times (0.5, 1.5, and 3 h). A thorough characterization of Ag-NSP/CHXg nanospheres has been carried out by dynamic light scattering (DLS), transmission electron microscopy (TEM), energy-dispersive surface elemental composition spectral analysis (SEM/EDX), Fourier transform infrared spectroscopy (FTIR), percentage (%) CHXg loading efficiency (LE), in vitro CHXg and Ag+ ion release, antibacterial/biofilm inhibition assay, and human mesenchymal stem cells (hMSCs) cytotoxicity evaluation. DLS measured nanospheres to be <160 nm and indicated that CHXg treatment drastically shifted the surface charge from negative to high positive values, with homogenous distribution. TEM revealed spherical Ag-NSP/CHXg nanospheres with a clearly visible surface coating of CHXg. FTIR confirmed association of CHXg with Ag-NSP nanospheres, whereas SEM/EDX data verified presence of spectral peaks specific to silver (Ag), CHXg, and PVP. The %LE gradually increased with increasing incubation times. In vitro CHXg release exhibited a bi-phasic fashion showing maximum release of ~74.83 ± 20.67% from Ag-NSP/CHXg-3h at 14 days. A slow release of Ag+ ions was detected; however, the surface decoration of Ag-NSP substantially hampered/restricted the liberation of ions. Agar well diffusion, MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H–tetrazolium), and crystal violet assay suggested good antibacterial/antibiofilm activity of Ag-NSP/CHXg that correlated with the increasing %LE of nanospheres. hMSCs cytotoxicity study showed low toxicity properties of all nanosphere formulations, except for Ag-NSP/CHXg-3h, affecting the cell viability at all proposed concentrations and exposure time points. CHXg accentuated the antibacterial properties of Ag-NSP. 相似文献
77.
Arafa Musa Ehab M. Mostafa Syed Nasir Abbas Bukhari Nasser Hadal Alotaibi Ahmed H. El-Ghorab Amr Farouk AbdElAziz A. Nayl Mohammed M. Ghoneim Mohamed A. Abdelgawad 《Molecules (Basel, Switzerland)》2022,27(4)
For most researchers, discovering new anticancer drugs to avoid the adverse effects of current ones, to improve therapeutic benefits and to reduce resistance is essential. Because the COX-2 enzyme plays an important role in various types of cancer leading to malignancy enhancement, inhibition of apoptosis, and tumor-cell metastasis, an indispensable objective is to design new scaffolds or drugs that possess combined action or dual effect, such as kinase and COX-2 inhibition. The start compounds A1 to A6 were prepared through the diazo coupling of 3-aminoacetophenone with a corresponding phenol and then condensed with two new chalcone series, C7–18. The newly synthesized compounds were assessed against both COX-2 and epidermal growth factor receptor (EGFR) for their inhibitory effect. All novel compounds were screened for cytotoxicity against five cancer cell lines. Compounds C9 and G10 exhibited potent EGFR inhibition with IC50 values of 0.8 and 1.1 µM, respectively. Additionally, they also displayed great COX-2 inhibition with IC50 values of 1.27 and 1.88 µM, respectively. Furthermore, the target compounds were assessed for their cytotoxicity against pancreatic ductal cancer (Panc-1), lung cancer (H-460), human colon cancer (HT-29), human malignant melanoma (A375) and pancreatic cancer (PaCa-2) cell lines. Interestingly, compounds C10 and G12 exhibited the strongest cytotoxic effect against PaCa-2 with average IC50 values of 0.9 and 0.8 µM, respectively. To understand the possible binding modes of the compounds under investigation with the receptor cites of EGFR and COX-2, a virtual docking study was conducted. 相似文献
78.
79.
Nehad A. Abd El-Latif Abd El-Galil E. Amr Alhusain A. Ibrahiem 《Monatshefte für Chemie / Chemical Monthly》2007,138(6):559-567
Summary. A series of substituted pyridine derivatives were prepared from 3-acetylpyridine, which was prepared from the corresponding
nicotinic acid as a natural starting material. Reaction of 3-acetylpyridine with indole-3-carboxaldehyde afforded the corresponding
3-β-(3-indolyl)acryloylpyridine, which was reacted with hydroxylamine hydrochloride in pyridine or acetic acid in the presence
of sodium acetate to afford 3-β-(3-indolyl)acryloylpyridine oxime and oxazole derivatives. The oxime was treated with ethyl
isothiocyanate or toluene-3,5-diisocyanate in refluxing dioxane to give the corresponding ethyl thiosemicarbazide and 3,5-bissemicarbazide
derivative. 3-β-(3-Indolyl)acryloylpyridine was condensed with malononitrile in refluxing ethanol in the presence of piperidine
as a catalyst to give cyanoaminopyrane, while it was condensed with ethyl cyanoacetate or malononitrile in the presence of
ammonium acetate to yield cyanopyridone and cyanoaminopyridine derivatives. Cyclization of acryloylpyridine with o-phenylenediamine in refluxing butanol led to the formation of the corresponding benzodiazipine via the intermediate A. Finally, cycloaddition reaction of acryloylpyridine with thiourea yielded thioxopyrimidine, which was treated with chloroacetic
acid to yield thiazolopyrimidine. An arylmethylene derivative was prepared by reacting thiazolopyrimidine with indole-3-carboxaldehyde
or by reacting thioxopyrimidine with indole-3-carboxaldehyde and chloroacetic acid in one step. The pharmacological screening
showed that many of these obtained compounds have good analgesic and anticonvulsant activities comparable to Valdecoxib? and Carbamazepine? as reference drugs. 相似文献
80.
Abd El-Galil E. Amr Nermien M. Sabry Mohamed M. Abdulla 《Monatshefte für Chemie / Chemical Monthly》2007,138(7):699-707
Summary. A series of pyridines, pyrimidinones, and oxazinones were synthesized as anti-inflammatory agents using citrazinic acid (2,6-dihydroxyisonicotinic
acid) as a starting material. Acryloyl pyridine was treated with cyanothioacetamide to give cyano pyridine-thione, which was
reacted with ethyl chloroacetate to yield the corresponding amino ester. The ester was hydrolysed to the sodium salt, which
was treated with acetic anhydride to afford 2-methyloxazinone, which was treated with ammonium acetate to afford 2-methylpyrimidinone
followed by methylation with methyl iodide to yield 2,3-dimethylpyrimidinone. In addition, the oxazinone derivative was reacted
with aniline or hydrazine hydrate to give 3-phenyl- or 3-aminopyrimidinones. The latter reacted with thiophene-2-carboxaldehyde
or phenylisothiocyanate to afford Schiff’s bases or thiosemicarbazides. 3-Aminopyrimidinone was treated with phthalic anhydride or 1,2,4,5-benzenetetracarboxylic
acid dianhydride or toluene-3,5-diisocyanate to afford the corresponding imide, bis-imide, and bis-semicarbazide derivatives. The pharmacological screening showed that many of these compounds have good anti-inflammatory
activity comparable to Prednisolone? as reference drug. 相似文献