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51.
Neil S. Keddie Geert Bultynck Tomas Luyten Alexandra M.Z. Slawin Stuart J. Conway 《Tetrahedron: Asymmetry》2009,20(6-8):857-866
The synthesis of d-myo-inositol 1,4,5-trisphosphate (InsP3) from methyl α-d-glucopyranose, via a type 2 Ferrier rearrangement is reported. A key intermediate in this synthesis possesses orthogonal protecting groups at the 1-, 4- and 5-position, making it a versatile starting point for the synthesis of unnatural InsP3 derivatives. Biological evaluation of the synthetic InsP3 demonstrates that this compound evokes selective Ca2+ release via activation of InsP3 receptors. 相似文献
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Nun P Gaillard S Slawin AM Nolan SP 《Chemical communications (Cambridge, England)》2010,46(48):9113-9115
The use of [(IPr)AuOH] permits the generation of gold(i)-amine complexes by a silver-free protocol. These in situ or well-defined complexes are used in a straightforward synthetic route to substituted allenes from propargylic acetates. The catalytic activity can be modulated as a function of the nature of the ligand bound to the gold-NHC moiety. 相似文献
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Self-injection length in La0.7Ca0.3MnO3-YBa2Cu3O7-δ ferromagnet-superconductor multilayer thin films
We have carried out extensive studies on the self-injection problem in barrierless heterojunctions between La0.7Ca0.3MnO3 (LCMO) and YBa2Cu3O7-δ (YBCO) thin films. The heterojunctions were formed in situ by sequentially growing LCMO and YBCO films on 〈100〉 LaAlO3 (LAO) substrate using a pulsed laser deposition (PLD) system. YBCO micro-bridges with 64 μm width were patterned both on
the LAO (control) and LCMO side of the substrate. Critical current, I
c, was measured at 77 K on both the control side as well as the LCMO side for different YBCO film thickness. It was observed
that while the control side showed a J
c of ∼ 2 × 106 A/cm2, the LCMO side showed about half the value for the same thickness (1800 ?). The difference in J
c indicates that a certain thickness of YBCO has become ‘effectively’ normal due to self-injection. From the measurement of
J
c at two different thicknesses (1800 ? and 1500 ?) of YBCO films both on the LAO as well as the LCMO side, the value of self-injection
length (at 77 K) was estimated to be ∼ 900 ?. To the authors’ best knowledge, this is the first time that self-injection length
has been quantified. A control experiment carried out with LaNiO3 deposited by PLD on YBCO did not show any evidence of self-injection. 相似文献
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