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41.
M. S. Abd El Halim A. Nada W. A. Gad 《Monatshefte für Chemie / Chemical Monthly》1994,125(12):1437-1442
Summary Aminolysis of 3-[2-(3,5-dimethylpyrazolyl)] succinic anhydride (1) leads to5. Hydrazine hydrate reacts with1a to give 4-(3,5-dimethylpyrazolyl)-1,2,4,5-tetrahydro-3,6-pyridazindione. The structures were confirmed by IR, MS,1H and13C NMR.
3-[2-(3,5-Dimethylpyrazolyl)]-succinanhydrid, ein Synthon für die Synthese einiger Heterocyclen mit potentieller pharmazeutisch nutzbarer Aktivität
Zusammenfassung Die Aminolyse von 3-[2-(3,5-Dimethylpyrazolyl)]-succinanhydrid (1) führt zu5. Hydrazinhydrat reagiert mit1a zu 4-(3,5-Dimethylpyrazolyl)-1,2,4,5-tetrahydro-3,6-pyridazindion. Die Strukturen wurden mittels IR, MS,1H-NMR und13C-NMR überprüft.相似文献
42.
Gregory Fridman Marie Peddinghaus Manjula Balasubramanian Halim Ayan Alexander Fridman Alexander Gutsol Ari Brooks 《Plasma Chemistry and Plasma Processing》2006,26(4):425-442
Thermal plasma discharges have been widely used in the past for treatment of living human and animal tissue. However, extensive thermal damage and tissue desiccation occurs due to extreme temperatures. Some solutions have been offered where the temperature is lowered by short current pulses, addition of noble gases, or significant decrease in the size of treatment electrodes. We propose a method of direct treatment of living tissue that occurs at room temperature and pressure without visible or microscopic tissue damage. The presented Floating-Electrode Dielectric Barrier Discharge plasma is proven electrically safe to human subjects and our results show no gross (visual) or histological (microscopic) damage to skin samples in minutes, complete tissue sterilization from skin flora in seconds, and blood clot formation in seconds of electric plasma treatment. We also observe significant hastening of blood clot formation via electric plasma induced catalysis of “natural” processes occurring in human blood. A model describing these processes is offered.An erratum to this article can be found at 相似文献
43.
Khalid M. Khan Nida Ambreen Muhammad Taha Sobia A. Halim Zaheer-ul-Haq Shagufta Naureen Saima Rasheed Shahnaz Perveen Sajjad Ali Mohammad Iqbal Choudhary 《Journal of computer-aided molecular design》2014,28(5):577-585
Using structure-based virtual screening approach, a coumarin derivative (1) was identified as β-glucuronidase inhibitor. A focused library of coumarin derivatives was synthesized by eco-benign version of chemical reaction, and all synthetic compounds were characterized by using spectroscopy. These compounds were found to be inhibitor of β-glucuronidase with IC50 values in a micromolar range. All synthetic compounds exhibited interesting inhibitory activity against β-glucuronidase, however, their potency varied substantially from IC50 = 9.9–352.6 µM. Of twenty-one compounds, four exhibited a better inhibitory profile than the initial hit 1. Interestingly, compounds 1e, 1k, 1n and 1p exhibited more potency than the standard inhibitor with IC50 values 34.2, 21.4, 11.7, and 9.9 µM, respectively. We further studied their dose responses and also checked our results by using detergent Triton ×-100. We found that our results are true and not affected by detergent. 相似文献
44.
Shimaa A. Atty Mona A. Mohamed Lobna M. AbdElHalim Fatma A. Fouad Rabah Boukherroub 《Electroanalysis》2019,31(7):1215-1223
A simple and efficient procedure is described for the electrochemical determination of ledipasvir (LDP) in presence of co‐formulated drug sofosbuvir (SOF). Herein, a highly sensitive, low‐cost electrochemical protocol was utilized to fabricate a zeolite modified carbon paste electrode (ZY/CPE) through mixing of zeolite nanostructures with graphite powder. The fabricated sensor displayed high sensitivity, allowing optimal charge transfer/electrode kinetics. Different experimental and chemical factors, including electrode composition, effect of pH, scan rate and amount of ZY were evaluated carefully to obtain the highest electrochemical response. Under optimized conditions and using square wave voltammetry (SWV), the current response of the ZY/CPE electrochemical sensing platform exhibited a detection limit of 7.5×10?9 M and a large linear range from 5.0×10?8 to 1.0×10?4 M. The practical applicability of the suggested electrochemical platform was verified in the assessment of LDP in pharmaceutical formulations with excellent recoveries in the range of 99.50–98.87 %. Moreover, a biological relevance of the developed sensor was established by the analysis of LDP in human urine and plasma samples with satisfactory recoveries of 99.00 and 99.68 %, respectively. Due to the simplicity and ease of preparation of the proposed sensor, it can be used in quality control laboratories and for clinical analysis. 相似文献
45.
Karki Surya B. Gupta Tripti Thapa Yildirim-Ayan Eda Eisenmann Kathryn M. Ayan Halim 《Plasma Chemistry and Plasma Processing》2020,40(1):99-117
Plasma Chemistry and Plasma Processing - Non-thermal plasma has been a promising new cancer treatment modality in plasma oncology field. It generates extracellular and intracellular reactive... 相似文献
46.
Chiheb Mhiri Lamia Boubakri Riadh Ternane Lamjed Mansour Abdel Halim Harrath J. Al-Tamimi Lassaad Baklouti Naceur Hamdi 《Journal of heterocyclic chemistry》2020,57(1):291-298
Three-component reaction of arylaldehydes with malononitrile and 4-hydroxycoumarine using CH3COONH4 as a catalyst at reflux was used for the synthesis of novel substituted pyrano[3,2-c]chromene derivatives. The structure of these compounds was assigned by spectroscopic data such as (IR, 1HNMR, 13CNMR, and mass spectral data). The cation binding properties of chromene derivatives 4a-c towards Cu2+, Ni2+, and Zn2+ were studied in methanol. The results showed that Zn2+ is the most complexed in this series of cations, and 4c is best complexed with either Ni2+ and Zn2+. Antimicrobial properties of new pyrano[3,2-c]chromene derivatives are investigated, the compound 4c presents against Micrococcus luteus LB 14110 an MIC value of 0.0185 mg/mL quite better to that of ampicillin (0.0195 mg/mL) used as standard. Concerning acetylcholinesterase inhibition activity (AChEI), compound 4c presents an interesting AChEI activity with an inhibition of 52%. 相似文献
47.
The synthesis of a new series of trans and racemic cis isomers of cobalt(III)‐, iron(III)‐, and chromium(III)‐based complexes with the α‐ and γ‐diimine Schiff base ligands, N,N′‐bis(X)‐2,3‐butandiimine and N,N′‐bis(X)‐1,2‐phenyldiimine (X = cyclohexyl, 2‐isopropylphenyl, 1‐naphthyl) is described. To confirm the identity of the complexes prepared in the present study, a variety of techniques including elemental analysis, magnetic susceptibility, infrared‐, mass‐ (EI), and UV/Vis‐ spectroscopy have been utilized. Some of the isolated complexes have been evaluated as catalysts for the oxidation of L‐cysteine. Preliminary results showed that the metal atoms, geometry of the complexes, auxiliary substituents, and the backbone of the ligand influenced the rate of oxidation reaction. 相似文献
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