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1.
Michela Iezzi Simone 《Tetrahedron letters》2005,46(34):5761-5765
Efficient SN2 ring closure of open chain trihydroxytriflates—in which the leaving group is on a primary carbon adjacent to a quaternary centre—provides access to tetrahydrofurans with branched carbon chains from branched carbohydrate lactones; the first examples of a new class of branched chain tetrahydrofuran α,α-disubstituted-δ-sugar amino acid scaffolds are described. 相似文献
2.
A. N. Yunuskhodzhaev EB. Shamuratov A. S. Batsanov S. A. Talipov 《Chemistry of Natural Compounds》1992,27(6):743-744
A single crystal of (RS)-carnitine hydrochloride has been obtained, and its crystal structure has been refined by an x-ray structural experiment.Tashkent Pharmaceutical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 842–844, November–December, 1991. 相似文献
3.
Trapped modes in acoustic waveguides 总被引:2,自引:0,他引:2
Davies EB; Parnovski L 《The Quarterly Journal of Mechanics and Applied Mathematics》1998,51(3):477-492
4.
Cai T Ge Z Iezzi EB Glass TE Harich K Gibson HW Dorn HC 《Chemical communications (Cambridge, England)》2005,(28):3594-3596
New pyrrolidino derivatives of both diamagnetic and paramagnetic trimetallic nitride templated endohedral metallofullerenes were synthesized by the Prato reaction, isolated and characterized by means of MALDI-TOF MS, NMR and UV-vis spectroscopies. 相似文献
5.
Carla Gasbarri Maurizio Ronci Antonio Aceto Roshan Vasani Gianluca Iezzi Tullio Florio Federica Barbieri Guido Angelini Luca Scotti 《Molecules (Basel, Switzerland)》2021,26(17)
The aim of this work was to deeply investigate the structure and properties of electrochemically synthesized silver nanoparticles (AgNPs) through high-resolution techniques such as transmission electron microscopy (TEM), scanning electron microscopy (SEM), Zeta Potential measurements, and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). Strong brightness, tendency to generate nanoclusters containing an odd number of atoms, and absence of the free silver ions in solution were observed. The research also highlighted that the chemical and physical properties of the AgNPs seemed to be related to their peculiar oxidative state as suggested by X-ray photoelectron spectroscopy (XPS) and X-ray powder diffraction (XRPD) analyses. Finally, the MTT assay tested the low cytotoxicity of the investigated AgNPs. 相似文献
6.
Silvio Mollo Gianluca Iezzi Guido Ventura Andrea Cavallo Piergiorgio Scarlato 《Journal of Non》2012,358(12-13):1624-1628
Pt-capsules loaded with a Pt-coil and two crystalline seeds immersed into an andesitic melt were rapidly cooled from 1300 to 1100 °C with a rate of 3 °C/min at atmospheric pressure and air oxygen fugacity. Results show that the Pt-coil does not induce any heterogeneous crystallization process as well as iron diffusion process from the melt into the platinum substrate. In contrast, the presence of crystalline seeds in a solidifying andesitic melt significantly alters the phase assemblage, composition and texture of the new-forming crystals in response to a heterogeneous nucleation mechanism and the formation of metastable phases. 相似文献
7.
Ma L Iezzi M Kaucher MS Lam YF Davis JT 《Journal of the American Chemical Society》2006,128(47):15269-15277
Lipophilic guanosine derivatives that form G-quadruplexes are promising building blocks for ionophores and ion channels. Herein, cation exchange between solvated cations (K+ and NH4+) and bound cations in the G-quadruplex [G1]16.4Na+.4DNP- was studied by electrospray ionization mass spectrometry and solution 1H, 15N NMR spectroscopy. The ESI-MS and 1H NMR data provided evidence for the formation of mixed-cationic Na+, K+ G-quadruplexes. The use of 15NH4+ cations in NMR titrations, along with 15N-filtered 1H NMR and selective NOE experiments, identified two mixed-cationic intermediates in the cation exchange pathway from [G1]16.4Na+.4DNP- to [G1]16.4NH4+.4DNP-. The central Na+, bound between the two symmetry-related G8-Na+ octamers, exchanges with either K+ or NH4+ before the two outer Na+ ions situated within the C4 symmetric G8 octamers. A structural rationale, based on differences in the cations' octahedral coordination geometries, is proposed to explain the differences in site exchange for these lipophilic G-quadruplexes. Large cations such as Cs+ can be exchanged into the central cation binding site that holds the two symmetry-related C4 symmetric G8 octamer units together. The potential relevance of these findings to both supramolecular chemistry and DNA G-quadruplex structure are discussed. 相似文献
8.
A. N. Yunuskhodzhaev EB. Shamuratov A. S. Batsanov S. A. Talipov 《Chemistry of Natural Compounds》1991,27(6):743-744
A single crystal of (RS)-carnitine hydrochloride has been obtained, and its crystal structure has been refined by an x-ray structural experiment. 相似文献
9.
A symmetric derivative of the trimetallic nitride endohedral metallofullerene, Sc3N@C80. 总被引:2,自引:0,他引:2
Erick B Iezzi James C Duchamp Kim Harich Tom E Glass Hon Man Lee Marilyn M Olmstead Alan L Balch Harry C Dorn 《Journal of the American Chemical Society》2002,124(4):524-525
The reaction of Sc3N@C80 with 6,7-dimethoxyisochroman-3-one (13C labeled) provides the first functionalized derivative of the trimetallic nitride template (TNT) endohedral metallofullerene family. The reaction mixture is dominated by a single 13C labeled monoadduct product that was purified by HPLC. The 13C labeled monoadduct was characterized by 1H NMR, 13C NMR, and MALDI-TOF mass spectrometry. The proposed structure for this novel symmetric monoadduct is consistent with derivatization at the [5,6] ring juncture on the Sc3N@C80 cage. 相似文献
10.