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321.
2-Amino-5-(2-aryl-2H-1,2,3-triazol-4-yl)-1,3,4-thiadiazoles 2-4 have been synthesized by the reaction of 2-aryl-2H-1,2,3-triazole-4-carboxylic acids 1 with thiosemicarbazide. Their reaction with phenacyl (p-substituted phenacyl) bromides led to formation of the respective 6-aryl-2-(2-aryl-2H-1,2,3-triazol-4-yl)imidazo[2,1-b]-1,3,4-thiadiazoles 5. Reactivity of the latter fused ring towards reaction with different electrophilic reagents afforded the corresponding 5-substituted derivatives 6-8. The structure of the above compounds was confirmed from their spectral characteristics. Some of these compounds were found to possess slight to moderate activity against the microorganisms Staphylococcus aureus, Candida albicans, Pseudomonas aeruginosa, and Escherichia coli. 相似文献
322.
Alaa S. Abd-el-aziz Adam Piórko Andrzej S. Baranski Ronald G. Sutherland 《合成通讯》2013,43(11-12):1865-1870
Electrochemical reduction of the cyclopentadienyliron hexafluorophosphates of benzophenone, o-chlorophenyldibenzoylmethane and diethyl ethylphenylmalonate led to the liberation of arenes without reduction of keto or ester groups in over 85% yields. 相似文献
323.
Alaa S. Abd-El-Aziz Sofia Tesfalidet Christine R. de Denus Krystyna Lezynska 《合成通讯》2013,43(10):1415-1426
A novel route to the synthesis of some 2-aryl alkanoic acid esters has been achieved. Aromatic nucleophilic substitution of various arene cyclopenta-dienyliron complexes with ethyl ethylacetoacetate and ethyl methylacetoacetate produced the complexed alkanoic acid esters. Photolysis of these complexes resulted in the liberation of the free esters in good yields. 相似文献
324.
Alaa A. Hassan Fathy F. Abdel‐Latif Ahmed M. Nour El‐Din Mohamed Abdel‐Aziz Sara M. Mostafa Stefan Bräse 《Journal of heterocyclic chemistry》2011,48(5):1050-1055
The reaction of 3‐(dicyanomethylene)‐2‐indolone in a solution of ethanol/piperidine with 4‐substituted thiosemicarbazides forms the derivatives of 5′‐(substituted amino)‐3′H–spiro(indoline‐3,2′‐[1,3,4]thiadiazol‐2‐one. Rationales for these conversions involving the nucleophilic addition on the dicyanomethylene carbon atom are presented. The prepared compounds were evaluated each for antidepressant activity using tail suspension behavioral despair test and anticonvulsant activity against pentylenetetrazol induced seizures in mice. J. Heterocyclic Chem., (2011). 相似文献
325.
Vrushali Guhe Farah Anjum Alaa Shafie Md Imtaiyaz Hassan Visweswara Rao Pasupuleti Shailza Singh 《Molecules (Basel, Switzerland)》2022,27(10)
In many regions of the world, Leishmaniasis is a cause of substantial mortality and ailment. Due to impediment in available treatment, development of novel and effective treatments is indispensable. Significance of autophagy has been accentuated in infectious disease as well as in Leishmaniasis, and it is having capability to be manifested as a therapeutic target. By evincing autophagy as a novel therapeutic regime, this study emphasized on the critical role of ATG4.1-ATG8 and ATG5-ATG12 complexes in Leishmania species. The objective here was to identify ATG8 as a potential therapeutic target in Leishmania. R71T, P56E, R18P are the significant mutations which shows detrimental effect on ATG8 while Arg276, Arg73, Cys75 of ATG4.1 and Val88, Pro89, Glu116, Asn117, and Gly120 are interacting residues of ATG8. Along with this, we also bring into spotlight an enticing role of Thiabendazole derivatives that interferes with the survival mechanisms by targeting ATG8. Further, the study claims that thiabendazole can be a potential drug candidate to target autophagy process in the infectious disease Leishmaniasis. 相似文献
326.
Alaa A. Hassan Aboul‐Fetouh E. Mourad Kamal M. El‐Shaieb Ashraf H. Abou‐Zied Dietrich Dpp 《Heteroatom Chemistry》2003,14(6):535-541
Microwave and thermal heterocyclization of N,N′‐disubstituted hydrazinecarbothioamide 1a,b and substituted thioureidoethylthioureas 2a–c as well as 1‐phenyl‐3[2‐(3‐phenylthio‐ureido)phenyl]thiourea 6 are reported. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:535–541, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10188 相似文献
327.
Alaa S. Abd-El-Aziz Erin K. Todd Rawda M. Okasha Tarek H. Afifi 《Macromolecular Symposia》2003,196(1):89-99
The synthesis of cationic organoiron polymers with azobenzene moieties in their side chains has been accomplished via nucleophilic aromatic substitution and ring-opening metathesis polymerization (ROMP) reactions. Polyaromatic ethers and thioethers with azobenzene moieties in their side chains were functionalized with different chromophores to yield yellow-, orange- and red-colored polymers. Polynorbornenes with azobenzene-containing side chains were isolated following ROMP of their monomeric analogs. All of the organoiron polymers were soluble in polar organic solvents and underwent reversible electrochemical reduction processes. Photobleaching of the azobenzene-containing polymers was achieved in the presence of hydrogen peroxide. The metallated polymers had glass transition temperatures approximately 50 to 80°C higher than their organic analogs. 相似文献
328.
Alaa S. Abd-El-Aziz Rawda M. Okasha Erin K. Todd Tarek H. Afifi Patrick O. Shipman K. Michelle D. Copping 《Macromolecular Symposia》2004,209(1):185-194
The synthesis of cationic cyclopentadienyliron-containing polymers with pendent azobenzene chromophores was accomplished via metal-mediated nucleophilic aromatic substitution reactions. All of the desired polymers were isolated as vibrantly coloured materials and displayed excellent solubility in polar aprotic solvents. Cationic and neutral cyclopentadienyliron polymers incorporating azo dyes in the backbone were also prepared. Reactions of azo dyes with dichlorobenzene complexes allowed for the isolation of cationic cyclopentdienyliron (CpFe+) complexes with azo dye chromophores. These complexes were then reacted with 1,1′-ferrocenedicarbonyl chloride to produce the trimetallic monomers with terminal chloro groups. These monomers contained two pendent CpFe+ cations and a neutral iron moiety in the backbone. Nucleophilic substitution reactions of these monomers with oxygen and sulfur containing dinucleophiles gave rise to a new class of polymeric materials. The pendent CpFe+ moieties could also be cleaved from the polymer backbones using photolysis to afford novel ferrocene based polymers. The UV-vis spectra of the organoiron monomers and polymers display similar wavelength maxima however incorporating azobenzene chromophores with electron-withdrawing substituent into the polymer chains resulted in bathochromic shifts of the λmax values. 相似文献
329.
Ala A. Alhusban Alaa M. Hammad Lujain F. Alzaghari Aliaa I. Shallan Khaldoun Shnewer 《Biomedical chromatography : BMC》2023,37(1):e5513
Tobacco smoking is a preventable main cause of fatal diseases. Accurate measurements of the effects it has on neurotransmitters are essential in developing new strategies for smoking cessation. Moreover, measurements of neurotransmitter levels can aid in developing drugs that counteract the effects of smoking. The aim of this study is to develop and validate a fast, simultaneous and sensitive method for measuring the levels of neurotransmitters in rat brain after the exposure of tobacco cigarettes. The selected neurotransmitters include dopamine, GABA, serotonin, glutamine and glutamate. The method is based on high-performance liquid chromatography–tandem mass spectrometry. Chromatographic separation was achieved within 3 min using a Zorbax SB C18 column (3.0 × 100 mm, 1.8 μm particle size). The mobile phase consisted of HPLC-grade water and acetonitrile each containing 0.3% heptafluorobutyric acid and 0.5% formic acid at gradient conditions. The linear range was 0.015–0.07, 825–7,218, 140–520, 63.42–160.75 and 38.25 × 103 to 110.35 × 103 ng/ml for dopamine, GABA, serotonin, glutamine and glutamate, respectively. Inter- and intra-run accuracy were in the range 97.82–103.37% with a precision (CV%) of ≤0.90%. The results revealed that 4 weeks of cigarette exposure significantly increased neurotransmitter levels after exposure to tobacco cigarettes in various brain regions, including the hippocampus and the amygdala. This increase in neurotransmitters levels may in turn activate the nicotine dependence pathway. 相似文献
330.
Phenylbiguanide reacts with some π-acceptors such as TCNE, TCNQ, CNIND, DCNQ, and CHL-o, if any. opy; 2003 Wiley Periodicals, Inc. Heteroatom Chem 15:63–66, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10213 相似文献