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Microwave-Assisted Preparation of 1-Aryl-1H-pyrazole-5-amines
Published on: June 23, 2019
Determination of absolute configuration in 4-aryl-3, 4-dihydro-2(1H)-pyrimidones by high performance liquid
1Institute of Organic Chemistry, Karl-Franzens-University Graz, Heinrichstrasse 28, A-8010 Graz, Austria.
Abstract:
The absolute configuration of three 4-aryl-3, 4-dihydro-2(1H)-pyrimidones (Biginelli compounds, DHPMs) was established by comparison of the typical circular dichroism (CD) spectra of individual enantiomers with reference samples of known absolute configuration. The enantiomers were obtained by semipreparative separation of racemic mixtures on a Chiralcel OD-H chiral stationary phase. The method was used to establish the enantiopreference of various lipases in biocatalytic kinetic resolution experiments employing activated DHPM esters.
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