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921.
Applications of multicomponent reactions for the synthesis of diverse heterocyclic scaffolds 总被引:1,自引:0,他引:1
A four-component coupling process involving sequential reactions of aldehydes, primary amines, acid chlorides, and nucleophiles has been developed to prepare multifunctional substrates that may be employed in subsequent ring-forming reactions to generate a diverse array of functionalized heterocyclic scaffolds. This new approach to diversity-oriented synthesis was then applied to the first total synthesis of the isopavine alkaloid (+/-)-roelactamine. 相似文献
922.
Arcon D Pregelj M Cevc P Rotas G Pagona G Tagmatarchis N Ewels C 《Chemical communications (Cambridge, England)》2007,(32):3386-3388
Density functional (DFT) calculations, high-temperature electron paramagnetic resonance (EPR) and transmission electron microscopy (TEM) results suggest that thermal homolysis of C59HN involves a remarkably stable intermediate C59N-C59HN* structure characterised by charge redistribution from a C59N* radical to a bonded C59HN. 相似文献
923.
Bailey CD Houlden CE Bar GL Lloyd-Jones GC Booker-Milburn KI 《Chemical communications (Cambridge, England)》2007,(28):2932-2934
A selective three-component coupling, involving co-condensation of aldehyde pairs with substituted ureas under Lewis acid catalysis, provides rapid access to highly functionalised dihydropyrimidinones; sulfamides react analogously. 相似文献
924.
925.
926.
The adsorption and reaction of acetic acid with Pd(110) have been studied using thermal molecular beam reaction measurements and temperature-programmed desorption. Acetic acid adsorption results in the formation of acetate species which decompose to produce coincident CO(2) and H(2) desorption from the surface. C is deposited on the surface from the dehydrogenation of the methyl group. In combination, these steps are found to exhibit unusual kinetics including (i) a "surface explosion" during heating and (ii) bistability in the reaction profile for heating and cooling curves. This is the first report of such behaviour for a complex system during in situ reaction. 相似文献
927.
Metal-enhanced Singlet Oxygen Generation: A Consequence of Plasmon Enhanced Triplet Yields 总被引:1,自引:0,他引:1
In this Rapid Communication, we report the first observation of Metal-Enhanced singlet oxygen generation (ME1O2). Rose Bengal in close proximity to Silver Island Films (SiFs) can generate more singlet oxygen, a three-fold increase observed,
as compared to an identical glass control sample but containing no silver. The enhanced absorption of the photo-sensitizer,
due to coupling to silver surface plasmons, facilitates enhanced singlet oxygen generation. The singlet oxygen yield can potentially
be adjusted by modifying the choice of MEF (Metal-Enhanced Fluorescence) & MEP (Metal Enhance Phosphorescence) parameters,
such as distance dependence for plasmon coupling and wavelength emission of the coupling fluorophore. This is a most helpful
observation in understanding the interactions between plasmons and lumophores, and this approach may well be of significance
for singlet oxygen based clinical therapy. 相似文献
928.
929.
Segall M Champness E Leeding C Lilien R Mettu R Stevens B 《Journal of chemical information and modeling》2011,51(11):2967-2976
In this article we describe a computational method that automatically generates chemically relevant compound ideas from an initial molecule, closely integrated with in silico models, and a probabilistic scoring algorithm to highlight the compound ideas most likely to satisfy a user-defined profile of required properties. The new compound ideas are generated using medicinal chemistry 'transformation rules' taken from examples in the literature. We demonstrate that the set of 206 transformations employed is generally applicable, produces a wide range of new compounds, and is representative of the types of modifications previously made to move from lead-like to drug-like compounds. Furthermore, we show that more than 94% of the compounds generated by transformation of typical drug-like molecules are acceptable to experienced medicinal chemists. Finally, we illustrate an application of our approach to the lead that ultimately led to the discovery of duloxetine, a marketed serotonin reuptake inhibitor. 相似文献
930.
Reeves DC Rodriguez S Lee H Haddad N Krishnamurthy D Senanayake CH 《Organic letters》2011,13(9):2495-2497
The palladium catalyzed alkoxycarbonylation and aminocarbonylation of vinyl tosylates are described. A variety of ketone and aldehyde derived vinyl tosylates may be carbonylated in the presence of primary, secondary, and tertiary alcohols, or primary and secondary amines, to provide the corresponding esters and amides in good yields. The alkoxycarbonylation was applied to a short synthesis of isoguvacine. 相似文献