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InspIRED by Nature: NADPH‐Dependent Imine Reductases (IREDs) as Catalysts for the Preparation of Chiral Amines
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Prof. Dr. Gideon Grogan Prof. Dr. Nicholas J. Turner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(6):1900-1907
Imine reductases (IREDs) are NADPH‐dependent oxidoreductases that catalyse the asymmetric reduction of cyclic prochiral imines to amines, with excellent stereoselectivity. Since their discovery, stereocomplementary IREDs have been applied to the production of both (S) and (R) cyclic secondary amines, and the expansion in gene sequences recently identified has hinted at new substrate ranges that extend into acyclic imines and even suggest the possibility of asymmetric reductive amination from suitable ketone and amine precursors. Structural studies of various IREDs are beginning to reveal the complexities inherent in determining substrate range, stereoselectivity and mechanism in these enzymes, which represent a valuable emerging addition to the toolbox of available biocatalysts for chiral amine production. 相似文献
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Simpson CD Brand JD Berresheim AJ Przybilla L Räder HJ Müllen K 《Chemistry (Weinheim an der Bergstrasse, Germany)》2002,8(6):1424-1429
In this paper we present the synthesis and characterization of the so far largest polycyclic aromatic hydrocarbon (PAH), containing 222 carbon atoms or 37 separate benzene units. First a suitable three-dimensional oligophenylene precursor molecule is built up by a sequence of Diels-Alder and cyclotrimerization reactions and then planarized in the final step by oxidative cyclodehydrogenation to the corresponding hexagonal PAH. Structural proof is based on isotopically resolved MALDI-TOF mass spectra and electronic characteristics are studied by UV/Vis spectroscopy. 相似文献
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Bennett GR Cuneo ME Vesey RA Porter JL Adams RG Aragon RA Caird JA Landen OL Rambo PK Rovang DC Ruggles LE Simpson WW Smith IC Wenger DF 《Physical review letters》2002,89(24):245002
An inertial-confinement-fusion (ICF) concept using two 60-MA Z pinches to drive a cylindrical hohlraum to 220 eV has been recently proposed. The first capsule implosions relevant to this concept have been performed at the same physical scale with a lower 20-MA current, yielding a 70+/-5 eV capsule drive. The capsule shell shape implies a polar radiation symmetry, the first high-accuracy measurement of this type in a pulsed-power-driven ICF configuration, within a factor of 1.6-4 of that required for scaling to ignition. The convergence ratio of 14-21 is to date the highest in any pulsed-power ICF system. 相似文献
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In this paper we investigate spectral matrices, i.e., matrices with equal spectral and numerical radii. Various characterizations and properties of these matrices are given. 相似文献
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