RESUMO
It has been demonstrated that besides the known flavanolignan constituents of the white-flowered variant of Silybum marianum, (-)-silandrin A (3a) and (-)-isosilandrin A (4a); their trans-benzodioxane diastereomers, (-)-silandrin B (3b) and (-)-isosilandrin B (4b), are also produced by the plant. Moreover, the isolation of their cis-benzodioxane diastereomers, (-)-isocisilandrin (5) and cisilandrin (6), confirm that the previously proposed biosynthetic pathway involving a nonselective O-beta coupling is correct.
Assuntos
Flavonolignanos/biossíntese , Flavonolignanos/isolamento & purificação , Silybum marianum/metabolismo , Vias Biossintéticas , Cromatografia Líquida de Alta Pressão , Flavonolignanos/química , Silybum marianum/química , Silimarina/análogos & derivados , Silimarina/química , Silimarina/isolamento & purificação , EstereoisomerismoRESUMO
A series of phenylbutene and butanol derivatives (6a-j, 12, 13, 15, 17, 24b,c, 26, 27a,b) were prepared from the readily available resorcinol derivatives 2a-f and 7-hydroxy-chroman (18). The products were tested for inhibitory activity on the LPS-induced TNF-alpha production in the plasma in comparison with that of cabenegrin A-I (1a).
