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Maryam Mohebbi Peyman Salehi Morteza Bararjanian Samad N. Ebrahimi 《Journal of the Iranian Chemical Society》2018,15(1):47-53
In this paper, synthesis of two derivatives of noscapine and their application as organocatalysts in the asymmetric addition of diethylzinc to aromatic aldehydes is reported. The first catalyst (2) was synthesized by the reduction of lactone ring of noscapine to form the corresponding diol, and the second one (3) was prepared by tert-butyl dimethyl silylation of the primary hydroxyl group of 2. Excellent yields and high ees up to 95% were obtained by using 3 as the catalyst. To the best of our knowledge, this is the first report on the application of lactone ring opened noscapinoid compounds as organocatalysts in asymmetric reactions. 相似文献
75.
M. Jafari M. Salehi M. Kubicki A. Khaleghian 《Russian Journal of Coordination Chemistry》2018,44(1):21-31
In the present study, two new zinc complexes with the chemical formulas of [Zn(2-Ampy)(Acac)2] (I) and [Zn(p-Van)2(H2O)2] (II) were synthesized and characterized by FT-IR, 1H NMR, and UV-Vis spectroscopy. Moreover, the crystal structures of the complexes were determined by X-ray diffraction technique. Single-crystal X-ray diffraction analyses (CIF files CCDC nos. 1513672 (I) and 1513673 (II)) revealed that complex I has a distorted square pyramid environment, and complex II has a distorted octahedral geometry. The complexes were also screened for in vitro antibacterial activities against some bacteria. The results show that complexes have the effective antibacterial activities. The complexes were employed to prepare ZnO nanoparticles by the combustion synthesis method at 700°C for 8 h. The nanoparticles were characterized, using powder X-ray diffraction analysis (PXRD), scanning electron microscopy and transmission electron microscope. PXRD analysis showed the presence of pure phase in both samples. Furthermore, the crystallite size was approximately 37 and 42 nm for ZnO prepared from complexes I and II, respectively. 相似文献
76.
Naader Alizadeh Mahsa Amiri Fariba Mohammadpour Parviz Norouzi 《Electroanalysis》2023,35(10):e202300114
This research represents a novel detection method of acetone level in the exhaled breath samples (RH=88 %) based on polypyrrole/tungsten oxide (PPy/WO3) nanocomposite sensor. The PPy/WO3 sensor was fabricated by the deposition of nanocomposite on/between interdigitated electrodes (IDEs) through electrospray coating and was then characterized by FE-SEM imaging. In this detection method, the coulometric signal of the sensor was calculated using Fast Fourier Continuous Cyclic Voltammetry (FFTCCV), where cyclic voltammetry (CV) was applied to the sensor in the defined potential rang and then charge changes of the sensor was obtained by integration of the current in all scanned potential ranges. FFTCCV method enhances the sensitivity of the sensor when exposed to the gas mixtures containing acetone. In addition to its fast coulometric response time (≤5 s) in the two linear ranges of 0.7–2.8 ppm and 2.8–28.2 ppm (R2=0.99), FFTCCV method provides the low detection limit of 70 ppb, and high sensitivity toward acetone at the optimum values of the parameters. The fabricated sensor showed great selectivity toward acetone when exposed to humid air and some exhaled gas like carbon dioxide, ammonia, methanol, ethanol and alkyl amines. The results were very satisfying as the sensor was capable to detect different acetone levels in human exhaled breath as non-invasive diagnosis of diabetes with a good correlation (R2≃0.9) to the routine blood sugar test taken by different commercial glucometers results. 相似文献
77.
Journal of Solid State Electrochemistry - Due to the spread of wireless devices, the need to improve batteries is felt more than ever. Orthorhombic vanadium pentoxide is one of the cathodes that... 相似文献
78.
Structure–Activity Studies of Cysteine‐Rich α‐Conotoxins that Inhibit High‐Voltage‐Activated Calcium Channels via GABAB Receptor Activation Reveal a Minimal Functional Motif 下载免费PDF全文
Dr. Bodil B. Carstens Dr. Géza Berecki James T. Daniel Han Siean Lee Kathryn A. V. Jackson Dr. Han‐Shen Tae Dr. Mahsa Sadeghi Dr. Joel Castro Tracy O'Donnell Dr. Annemie Deiteren Prof. Stuart M. Brierley Prof. David J. Craik Prof. David J. Adams Dr. Richard J. Clark 《Angewandte Chemie (International ed. in English)》2016,55(15):4692-4696
α‐Conotoxins are disulfide‐rich peptides that target nicotinic acetylcholine receptors. Recently we identified several α‐conotoxins that also modulate voltage‐gated calcium channels by acting as G protein‐coupled GABAB receptor (GABABR) agonists. These α‐conotoxins are promising drug leads for the treatment of chronic pain. To elucidate the diversity of α‐conotoxins that act through this mechanism, we synthesized and characterized a set of peptides with homology to α‐conotoxins known to inhibit high voltage‐activated calcium channels via GABABR activation. Remarkably, all disulfide isomers of the active α‐conotoxins Pu1.2 and Pn1.2, and the previously studied Vc1.1 showed similar levels of biological activity. Structure determination by NMR spectroscopy helped us identify a simplified biologically active eight residue peptide motif containing a single disulfide bond that is an excellent lead molecule for developing a new generation of analgesic peptide drugs. 相似文献
79.
Five new Ni(II) Schiff base complexes [NiLx(Solv)2] denoted by NiLx, x = 1–5, were synthesized and characterized. The Schiff base ligands were synthesized from the condensation of 5-bromo-2-hydroxy-3-nitrobenzaldehyde with different aliphatic and aromatic diamines. The X-ray crystal structure of NiL3 was determined. The ligands and complexes were tested as antibacterial agents against two gram(+) and two gram(?) human pathogenic bacteria. The complexes showed moderate antibacterial activity against both gram type bacteria. The new Ni(II) complexes showed enhanced antibacterial activity compared to the previously reported Cu(II) complexes of the same ligands. 相似文献
80.
The purpose of this paper is to generalize and improve some topological properties of solutions set to the set-valued vector equilibrium problems by using the scalar characterization method. Moreover, the Lipschitz continuity of an approximate solution mapping for the parametric set-valued vector equilibrium problems is studied. 相似文献