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151.
Conducting poly(o-anisidine) coatings were obtained on low carbon steel in aqueous oxalic acid solution by using the galvanostatic technique. The coatings were characterised by potential-time relations, UV-VIS absorption spectroscopy, scanning electron microscopy, and X-ray diffraction measurements. The electrochemical performance of coated steel electrodes was evaluated on the basis of galvanostatic charge-discharge performance and electrochemical impedance spectroscopy in 0.5 M H2SO4. Maximum charging current was found in the case of the coating obtained at a current density of 8 mA cm?2 for 600 s duration at the supply voltage of 0.5 V. The estimated capacitance of the coated steel electrode for charging is 42.67 mF and 7.2 mF for discharging. It was also found that there was an increase in capacitance as a function of supply voltage and the maximum value was obtained at 0.5 V. The study reveals the possibility of using conducting poly(o-anisidine)-coated low carbon steel from oxalic acid medium as supercapacitor electrode materials.  相似文献   
152.
The oxy hydrindenone derivative 6b was converted stereoselectively into the corresponding γ-isopropyl derivative 10 by a five-step sequence.  相似文献   
153.
The reductive coupling of aromatic aldehydes and ketones has been achieved using a catalytic amount of zirconocene dichloride in the presence of magnesium metal and chlorotrimethylsilane in THF at room temperature to afford the corresponding 1,2‐diols in good yields and diastereoselectivity.  相似文献   
154.
The increased acidity of the α-protons of 3,3,3-trifluoropropionates was exploited to achieve the enolboration of these esters using dialkylchloroboranes.  相似文献   
155.
El Kaim L  Grimaud L  Patil P 《Organic letters》2011,13(5):1261-1263
A three-component strategy starting from isocyanides allows a straightforward synthesis of five-membered ring heterocycles. New cascades were developed involving the addition of a nitrogenated nucleophile-an azide or a tetrazole-on isocyanide dibromides, an electrocyclization, and a Suzuki coupling, which afford new accesses to tetrazole and triazole scaffolds.  相似文献   
156.
A short sequential synthesis of pyrrolidino- pyridines and pyrimidines illustrates the potential of combining Ugi-Smiles couplings with radical tin-free processes.  相似文献   
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158.
We present molecular docking studies on the inhibitors of GSK-3beta kinase in the enzyme binding sites of the X-ray complexes (1H8F, 1PYX, 1O9U, 1Q4L, 1Q5K, and 1UV5) using the Schr?dinger docking tool Glide. Cognate and cross-docking studies using standard precision (SP) and extraprecision (XP) algorithms have been carried out. Cognate docking studies demonstrate that docked poses similar to X-ray poses (root-mean-square deviations of less than 2 A) are found within the top four ranks of the GlideScore and E-model scores. However, cross-docking studies typically produce poses that are significantly deviated from X-ray poses in all but a couple of cases, implying potential for induced fit effects in ligand binding. In this light, we have also carried out induced fit docking studies in the active sites of 1O9U, 1Q4L, and 1Q5K. Specifically, conformational changes have been effected in the active sites of these three protein structures to dock noncognate ligands. Thus, for example, the active site of 1O9U has been induced to fit the ligands of 1Q4L, 1Q5K, and 1UV5. These studies produce ligand docked poses which have significantly lower root-mean-square deviations relative to their X-ray crystallographic poses, when compared to the corresponding values from the cross-docking studies. Furthermore, we have used an ensemble of the induced fit models and X-ray structures to enhance the retrieval of active GSK-3beta inhibitors seeded in a decoy database, normally used in Glide validation studies. Thus, our studies provide valuable insights into computational strategies useful for the identification of potential GSK-3beta inhibitors.  相似文献   
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160.
In the present investigation, a novel series of 2‐[(2‐arylthiazol‐4‐yl)methyl]‐5‐(alkyl/alkylnitrile thio)‐1,3,4‐oxadiazole derivatives were synthesized by cyclo‐condensation of 2‐(2‐substituted thiazol‐4‐yl)aceto hydrazide with carbon disulfide followed by S‐alkylation with alkyl halide in dry acetone. All the newly synthesized compounds were characterized by spectral (IR, 1H NMR, 13C NMR, mass, and elemental analysis) methods. The title compounds were screened for in vitro antifungal activity and most of the synthesized compounds show moderate to good antifungal activity.  相似文献   
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