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1.
The efficient Fmoc solid-phase peptide synthesis of the 37-residue human Amylin and its amyloidogenic 8-37 fragment was achieved using pseudoproline (oxazolidine) dipeptide derivatives. Syntheses of hAmylin(8-37) using Fmoc amino acids produced only traces of the desired peptide. Incorporation of pseudoproline dipeptides produced the desired product with high yield and allowed for the synthesis of the full length peptide. The crude material was pure enough to allow formation of the Cys-2 to Cys-7 disulfide by air oxidation. [Structure: see text] 相似文献
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Farhad Shirini Mohammad Ali Zolfigol Masoumeh Abedini 《Monatshefte für Chemie / Chemical Monthly》2009,141(10):61-64
Abstract
Saccharin sulfonic acid was easily prepared by the reaction of saccharin with neat chlorosulfonic acid at room temperature. This reagent is efficiently able to catalyze the chemoselective trimethylsilylation of alcohols with hexamethyldisilazane in the presence of amines and thiols. 相似文献3.
Hossein Ali Khonakdar Mahdi Golriz Seyed Hassan Jafari Hossein Abedini Udo Wagenknecht Gert Heinrich 《Macromolecular theory and simulations》2012,21(5):340-349
Transreactions of PET and PEN melt‐mixed in a twin‐screw extruder are investigated. The extruder is modeled and characterized in the frame of a tubular system of closed type. The kinetic modeling is based on a modified second‐order reversible reaction equation, which allows the dispersion equation to be solved analytically. The analysis shows a good agreement between the model and experiment. The axial dispersion model is employed to predict the extent of transesterification reactions (X) and degree of randomness (RD). 1H NMR measurements are performed to estimate X and RD. Theoretical and experimental data are in good agreement. The model can thus be exploited to describe the effects of processing parameters, mixing time, mixing temperature, and blend composition on X and RD.
4.
Farhad Shirini Masoumeh Abedini Somayeh Akbari-Dadamahaleh Arman Rahmaninia 《Journal of the Iranian Chemical Society》2014,11(3):791-824
Xanthenes and their derivatives as very important classes of organic compounds are key structural elements of many biologically active compounds. These materials are important heterocyclic nucleus of various dyes and drugs. Because of their wide range of pharmacological, industrial and synthetic applications, many methods for the preparation of xanthenes are reported in the literature. In recent years, among the other chemists, introduction of new methods for the preparation of these types of compounds has attracted the attention of Iranian chemists. The result of these efforts is the introduction of appropriate, effective and efficient methods. In this paper, we have a brief review on these methods and their main advantages and important applicabilities. 相似文献
5.
Two different shear sample geometries were employed to investigate the failure behaviour of two automotive alloy rolled sheets; a highly anisotropic magnesium alloy (ZEK100) and a relatively isotropic dual phase steel (DP780) at room temperature. The performance of the butterfly type specimen (Mohr and Henn Exp Mech 47:805–820, 16; Dunand and Mohr Eng Fract Mech 78:2919-2934, 17) was evaluated at quasi-static conditions along with that of the shear geometry of Peirs et al Exp Mech 52:729-741, (27) using in situ digital image correlation (DIC) strain measurement techniques. It was shown that both test geometries resulted in similar strain-paths; however, the fracture strains obtained using the butterfly specimen were lower for both alloys. It is demonstrated that ZEK100 exhibits strong anisotropy in terms of failure strain. In addition, the strain rate sensitivity of fracture for ZEK100 was studied in shear tests with strain rates from quasi-static (0.01 s?1) to elevated strain rates of 10 and 100 s?1, for which a reduction in fracture strain was observed with increasing strain rate. 相似文献
6.
Abedini A. Armaghani T. Chamkha Ali J. 《Journal of Thermal Analysis and Calorimetry》2019,135(1):685-695
Journal of Thermal Analysis and Calorimetry - In this paper, the effect of a baffle on free convection heat transfer of a water–Fe3O4 nanofluid in a C-shaped enclosure in the presence of a... 相似文献
7.
Esmaeili Hossein Armaghani T. Abedini A. Pop I. 《Journal of Thermal Analysis and Calorimetry》2019,135(6):3247-3257
Journal of Thermal Analysis and Calorimetry - The nanofluid is a mixture of base fluid and solid nanoparticles in nanosize. The heat transfer generated by the nanofluid is more than the base fluid... 相似文献
8.
In the present study, the synthesis of mordenite zeolite/MIL‐101(Cr) metal–organic framework (MOF) composite [MOR/MIL‐101(Cr)] using the ship in a bottle method was suggested. The properties of prepared composite and individual MOF and MOR zeolite were characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption–desorption measurement, and thermogravimetric analysis (TGA). The XRD results indicated diffraction peaks for each compound (MOR and MOF) in composite. The SEM and TEM images showed the formation of plates MOR (with size of 2.5 × 3 μm) along with spherical particles MIL‐101. The Brunauer–Emmett–Teller results showed that the surface area of the composite was smaller than individual MOF and MOR zeolite. Based on TGA plots, the hybrid zeolite/MOF composite was more thermally stable compared with the isolated MIL‐101(Cr). The composite was functionalized by post‐synthetic modification to obtain acid–base bifunctionality (H‐MOR/MIL‐101‐ED) for the synthesis of chromene derivatives. The acidity from framework Al‐O(H)‐Si sites in MOR and basicity from amine groups in MIL‐101 were obtained by post‐synthetic modification. 相似文献
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Abedini Masoumeh Shirini Farhad Mohammad-Alinejad Omran Javad Seddighi Mohadeseh Goli-Jolodar Omid 《Research on Chemical Intermediates》2016,42(5):4443-4458
Research on Chemical Intermediates - Succinimidinium N-sulfonic acid hydrogen sulfate ([SuSA-H]HSO4) as a new ionic liquid is prepared and characterized using a variety of techniques, including... 相似文献