Lignans synthesis

Umezawa T, Kuroda H, Isohata T et al (1994) Enantioselective lignan synthesis by cell-free extracts of Forsythia koreana. Biosci Biotech Biochem 58 230-234... 

Scheme 4.17 Push-pull ylides for lignan synthesis.

Keywords Biological Activity Biosynthesis Lignans Synthesis Taxaceae Taxus... 

There are various approaches to lignan synthesis. Although some of them are well known reactions that have been used for many years, there are also much newer approaches too. The approaches are listed and explained below. 

Diels-Alder reactions have been widely used to synthesize lignans, particularly the arylnaphthalene and aryltetralin types. This was one of the first examples of the use of an znfermolecular (as opposed to an intramolecular) Diels-Alder reaction for lignan synthesis. The approach includes the use of an arylisobenzofuran (Fig. 4) generated in situ as diene and dimethylacetyl-enedicarboxylate (DMAD) as the dienophile (Fig. 4). The Diels-Alder prod-... 

Lactases 976 Lamiaceae 967 Langmuir isotherm 944 Lariciresinol, enzymatic formation of 1216 Lead compounds, as oxidants 1292, 1325-1330 Leguminosae 967 Lewis acid catalysis 607-611, 631 Lignans, synthesis of 1158, 1242, 1274 Lignin model compounds 302-306, 867, 868 phosphitylation of 999 Lignins 962, 997, 998... 

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