Cis-trans Isomerization of silybins A and B.
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ABSTRACT:
SUBMITTER: Novotna M
PROVIDER: S-EPMC4077359 | biostudies-literature | 2014
REPOSITORIES: biostudies-literature
Publications
cis-trans Isomerization of silybins A and B.
Novotná Michaela M Gažák Radek R Biedermann David D Di Meo Florent F Marhol Petr P Kuzma Marek M Bednárová Lucie L Fuksová Kateřina K Trouillas Patrick P Křen Vladimír V
Beilstein journal of organic chemistry 20140508
Methods were developed and optimized for the preparation of the 2,3-cis- and the 10,11-cis-isomers of silybin by the Lewis acid catalyzed (BF3∙OEt2) isomerization of silybins A (1a) and B (1b) (trans-isomers). The absolute configuration of all optically pure compounds was determined by using NMR and comparing their electronic circular dichroism data with model compounds of known absolute configurations. Mechanisms for cis-trans-isomerization of silybin are proposed and supported by quantum mecha ...[more]
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