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931.
高效和可重复使用的Zr-MCM-41催化剂催化Strecker反应合成氨基腈类化合物(英文) 总被引:1,自引:0,他引:1
The synthesis and characterization of Zr-MCM-41 nanoreactors and their catalytic activity in the synthesis of new amino nitrile derivatives by the Strecker reaction in high yields and in short reaction times is reported. 相似文献
932.
Arash Ghorbani-Choghamarani Maryam Hajjami Hamid Goudarziafshar Mohsen Nikoorazm Shadpour Mallakpour Fatemeh Sadeghizadeh Gouhar Azadi 《Monatshefte für Chemie / Chemical Monthly》2009,12(4):607-610
Abstract
A simple and efficient catalytic oxidation of urazoles and a bis-urazole to the corresponding triazolinediones by treatment with Al(NO3)3.9H2O in the presence of a catalytic amount of silica sulfuric acid is described. A good range of urazole derivatives was selectively oxidized in CH2Cl2 at room temperature in good to excellent yields. 相似文献933.
Hossien A. Oskooie Majid M. Heravi Akbar Sadnia Fatemeh Jannati Farahnaz K. Behbahani 《Monatshefte für Chemie / Chemical Monthly》2008,139(1):27-29
Summary. The multicomponent Strecker reaction using trimethylsilyl cyanide was performed at room temperature and α-aminonitriles were prepared in excellent yields
in the presence of a catalytic amount of H2SO4 adsorbed on silica gel. 相似文献
934.
The formation constants of the species formed in the systems H+ + dimethyltin(IV) + 5′‐IMP and 5′‐UMP, H+ + 5′‐IMP and H+ + 5′‐UMP have been determined in aqueous solution in the pH range 1.5–9.5 at constant temperature (25 °C) and constant ionic strength (0.1 mol dm−3 NaClO4), using spectrophotometric and potentiometric techniques. 1H and 31P NMR investigations in aqueous solution confirmed the species formation. The precipitated complexes of IMP and UMP by Me2Sn(IV)2+ at low pH values were characterized by elemental analysis and FTIR spectroscopy methods, the bonding sites of the ligands were determined and ruled out purine and pyrimidine moieties (N‐7 and N‐1 in IMP and N‐3 in UMP, respectively) while a bidentated coordination of the phosphate group is concluded in both cases. Finally, the experiments revealed the existence of complexes with trigonal bipyramidal structures that is in agreement with similar systems resulted previously. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
935.
Fabrication of chain-like Mn2O3 nanostructures via thermal decomposition of manganese phthalate coordination polymers 总被引:1,自引:0,他引:1
Masoud Salavati-Niasari Fatemeh Mohandes Kamal Saberyan 《Applied Surface Science》2009,256(5):1476-1480
A novel manganese coordination polymer [Mn(Pht)(H2O)]n as a precursor was obtained by chemical precipitation involving an aqueous solution of anhydrous manganese acetate and phthalate anion as a potential O-banded ligand. Fourier transform infrared (FT-IR) results proved that phthalate anions coordinate to metal cations as a chelating bidentate ligand, making polymeric structure. The Mn2O3 nanostructures have been prepared via thermal decomposition of as-prepared manganese phthalate polymers as precursor in the presence of oleic acid (OA) and triphenylphosphine (TPP) as a stabilizer and capping. Different approaches such as FT-IR, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were applied to characterize the products. TEM images and XRD analysis indicated that the as-synthesized chain-like Mn2O3 has a crystal phase of cubic syngony with a mean size of ∼40 nm. 相似文献
936.
Majid M. Heravi Samaheh Sadjadi Sodeh Sadjadi Hossein A. Oskooie Fatemeh F. Bamoharram 《Ultrasonics sonochemistry》2009,16(6):708-710
A new synthesis of 4(3H)-quinazolinone from the reaction of 2-amino-benzamide, and acylchlorides in the presence of catalytic amounts of silica-supported Preyssler nano particles as green, reusable and efficient catalyst under ultra sonic irradiation is reported. 相似文献
937.
Structural Chemistry - Kinesin Eg5 plays an essential role in the early stages of mitosis, and it is an interesting drug target for the design of potent inhibitors. In this work, combined molecular... 相似文献
938.
ABSTRACTLipids and DNAs are two major building blocks of life. Interestingly, by chemically linking these two natural compounds together, synthetic lipid-DNA conjugates exhibit several attractive features for cell membrane studies. These lipid-DNA conjugates are amphiphilic macromolecules combining the cell membrane insertion capability of lipids with the properties of DNAs in precise hybridization and programmability. These supramolecular conjugates have demonstrated exciting applications from generating cell membrane nanopores to transmembrane cargo deliveries, and from analyzing cell membrane events to tissue engineering. In this review, we will discuss the design, structures, and biological applications of lipid-DNA conjugates, with an emphasis on their functions on live cell membranes. We expect, in the near future, significant advancement in our ability to understand, control, and apply these cell membrane-modified lipid-DNA conjugates. 相似文献
939.
BiBi Fatemeh Mirjalili Abdolhamid Bamoniri Leila Rahmati 《Arabian Journal of Chemistry》2019,12(8):2216-2223
1-Amidoalkyl-2-naphthols were prepared via one-pot multi-component reaction of 2-naphthol, aldehydes, and amides in the presence of nano-silica supported boron trifluoride (nano-BF3·SiO2) in ethyl acetate at 80 °C. Short reaction times, high yields, scaleup and easy work-up are the advantages of this protocol. 相似文献
940.
Fatemeh Taghipour Masoud Mirzaei 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(3):231-247
The important role of pyrazine (pz) and its derivatives in fields such as biochemistry and pharmacology, as well as in the study of magnetic properties, is surveyed. Recognition of these properties without extensive investigations into their structural properties is not possible. This review summarizes interactions that exist between these organic compounds by themselves in the solid state, as well as those in coordination polymers with metal ions and in polyoxometalate‐based hybrids. Complexes based on pyrazine ligands can generate metal–organic framework (MOF) structures that bind polyoxometalates (POMs) through covalent and noncovalent interactions. Some biological and magnetic properties involving these compounds are considered and the effect of hydrogen bonding on their supramolecular architectures is highlighted. 相似文献