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891.
Morteza Bahram Sima Mojarrad Mehdi Moghtader 《Journal of the Iranian Chemical Society》2018,15(4):779-786
Determination of pharmaceutical analytes has been subjected to many investigations, especially in transplantations in which accurate and precise detection of drugs is of importance. In this study, a simple and fast complexation reaction has been employed for simultaneous kinetic–spectrophotometric determination of two immunosuppressant drugs, mycophenolate mofetil and its active metabolite mycophenolic acid, which is based on the reaction between drugs and Fe(III) ions in the presence of sodium dodecyl sulfate as anionic surfactant by standard addition method. The effect of influential parameters including type of surfactant, concentration of Fe(III) ions and pH of the solution on the complexation reaction has been studied, and SDS was chosen as suitable surfactant, while reaction proceeds with 0.1 M Fe(III) at pH 4. Multivariate curve resolution-alternating least squares has been employed for analyzing the multiset data obtained from augmentation of resulting standard addition matrices. Values for limit of detection of method have been calculated as 4.88 and 1.62 µg mL?1 for mycophenolic acid and mycophenolate mofetil, respectively, and Beer’s law is obeyed over the concentration ranges 10–200 µg mL?1 for MPM and 50–250 µg mL?1 for MPA. The proposed method was successfully applied for determination of drugs in plasma serum samples. The accuracy and reliability of the method was further ascertained by recovery studies via standard addition procedure. 相似文献
892.
Sayed Habib Kazemi Hojjat Kazemi Mehdi Kabiri-Samani M. A. Kiani 《Journal of the Iranian Chemical Society》2018,15(9):2117-2122
Herein, we introduce the application of nickel hydroxide nanosheets on the electro-etched carbon fiber (ECF) formed via a direct electrodeposition, for fabrication of asymmetric supercapacitor. To confirm the practical applicability of prepared Ni(OH)2–ECF, an asymmetric device was assembled using Ni(OH)2–ECF in combination with an activated carbon (AC) electrode. Our results showed a substantial cycling stability (96% capacitance retention after 10000 cycles) and considerable rate capability at large discharge currents (60% capacitance retention at 8 A g??1) for this asymmetric supercapacitor that may have originated from the good contact between Ni(OH)2 and ECF. A maximum specific capacitance of 88.1 F g??1 was achieved for Ni(OH)2–ECF//AC/CF device and showed considerable rate capability at large discharge currents (60% capacitance retention at 8 A g??1). The results of this study suggest the Ni(OH)2–ECF electrode is an excellent material for fabrication of supercapacitor electrodes. 相似文献
893.
Corrigendum: Vicinal Disulfide Constrained Cyclic Peptidomimetics: a Turn Mimetic Scaffold Targeting the Norepinephrine Transporter
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894.
A novel one-pot, multi-component diastereoselective synthesis of functionalized cyclopenta[c]chromenes is described. This transformation proceeds via a Michael addition-cyclization reaction sequence between trialkyl phosphites, dialkyl acetylenedicarboxylates and in situ generated 2-(1-(2-oxo-2H-chromen-3-yl)alkylidene)malononitriles from the condensation of 3-acyl-2H-chromen-2-ones and malononitrile. 相似文献
895.
DNA‐Templated [2+2] Photocycloaddition: A Straightforward Entry into the Aplysinopsin Family of Natural Products
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Nicolas Duchemin Adam Skiredj Justine Mansot Karine Leblanc Dr. Jean‐Jacques Vasseur Dr. Mehdi A. Beniddir Dr. Laurent Evanno Prof. Dr. Erwan Poupon Prof. Dr. Michael Smietana Dr. Stellios Arseniyadis 《Angewandte Chemie (International ed. in English)》2018,57(36):11786-11791
Biosynthetic considerations inspired us to harness the templating properties offered by DNA to promote a [2+2] photoinduced cycloaddition. The method was developed based on the dimerization of (E)‐aplysinopsin, which was previously shown to be unproductive in solution. In sharp contrast, exposure of this tryptophan‐derived olefin to light in the presence of salmon testes DNA (st‐DNA) reproducibly afforded the corresponding homo‐dimerized spiro‐fused cyclobutane in excellent yields. DNA provides unique templating interactions enabling a singular mimic of the solid‐state aggregation necessary for the [2+2] photocycloaddition to occur. This method was ultimately used to promote the prerequisite dimerizations leading to both dictazole B and tubastrindole B, thus constituting the first example of a DNA‐mediated transformation to be applied to the total synthesis of a natural product. 相似文献
896.
897.
A facile, mild and efficient procedure for the synthesis of fully substituted pyrazolo[3,4-b]pyridin-5-amines is reported. A mixture of an α-azidochalcone, a 5-aminopyrazole and t-BuOK was stirred in DMF at ambient temperature for 5?min to afford the corresponding pyrazolo[3,4-b]pyridin-5-amines in good to excellent yields. 相似文献
898.
A mild, general and efficient copper-catalyzed system for C-S bond formation is developed. With CuI as catalyst and l-Proline as ligand, the S-arylation of nitroalkane-CS2 adducts with aryl iodides were performed under mild conditions to give the corresponding products in good to excellent yields. 相似文献
899.
Tadesse Bekele Tafesse Fatemeh Zamani Mazdeh Anita Chalipour Mehdi Tavakoli Mannan Hajimahmoodi Mohsen Amini 《Chromatographia》2018,81(3):501-508
A gas chromatography–mass spectrometry method for the determination of pregabalin in human plasma is described. The procedure involves precipitation of protein, liquid–liquid extraction with ethylene glycol monomethyl ether, and derivatization with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide in the presence of N-hydroxysuccinimide as additive. Separation was attained on HP column (30 m × 0. 25 mm ID, 0.25 μm) coupled with mass spectrometric detector using electron impact selected ion monitoring. The assay showed an excellent linearity in the concentration range of 0.36–10 μg mL?1 with correlation coefficient (r2) values of 0.999. The intra- and inter-day assay variations for three different concentration levels were less than 10%. The limit of quantification was detected at 0.36 μg mL?1. The method is highly specific, precise, accurate, and reproducible and could also be applied for the determination of pregabalin in human plasma. 相似文献
900.
Modified clay/polyethersulfone (PES) mixed matrix membranes (MMMs) were prepared by acid activated montmorillonite (AA-MMT) with different concentrations and used to eliminate dyes and remove heavy metals from aqueous solution.The morphology and physiochemical properties of prepared clay nanoparticles and MMMs were characterized using X-ray diffraction (XRD),Fourier transform infrared (FTIR) spectroscopy,scanning electron microscopy (SEM),enegy dispersive X-ray (EDX) spectroscopy,Brunauer-Emmett-Teller (BET) analysis,atomic force microscopy (AFM),contact angle measurement and fouling studies.The filtration study showed that removal of dyes and heavy metals was strongly dependent on pH so that dyes with positive and negative charges showed different separation efficiency in acidic and alkaline conditions.The modified membranes possessed better heavy metal removal in acidic and alkaline pHs.When the rejection of heavy metals was measured in an alkaline environment,it was observed that the rejection had a great increase compared to the neutral values for Zn2+ and Ni2+ ions,while rejection of Cu2+ and Cd2+ did not undergo significant changes.So it can be concluded that modified membranes show good selectivity for elimination of Zn2+ and Ni2+ ions with respect to other cations. 相似文献