Zusammenfassung
The stereoselective Pd-catalyzed allylation of MBA [5-(2'hex-3'-ynyl)-1-methylbarbituric acid] gives the commercial injection narcotic methohexital, which exists as four isomers: two diastereomeric pairs of enantiomers. The isomer composition produced depends on three stereochemical parameters: catalyst control, substrate control, and kinetic resolution. Judicious choice of these parameters ...
Zusammenfassung
The stereoselective Pd-catalyzed allylation of MBA [5-(2'hex-3'-ynyl)-1-methylbarbituric acid] gives the commercial injection narcotic methohexital, which exists as four isomers: two diastereomeric pairs of enantiomers. The isomer composition produced depends on three stereochemical parameters: catalyst control, substrate control, and kinetic resolution. Judicious choice of these parameters allowed the synthesis of methohexital samples with greatly differing isomer compositions, and these samples were investigated with re-spect to their anaesthetic doses in rats. Some isomer compositions obtained were much more active than the commercially used drug and showed fewer side effects. As a consequence of the determination of the absolute configuration of the methohexital (SbRh) isomer, the unknown configuration of the trade product, the so-called a-racemate, can be established as (RbSh) and (SbRh). (C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.