Coumestan glycoside

Coumestans, such as (88), which possess a coumarin strac-ture, are derivatives of isoflavones (Fig. 11.28) most of the 31 known compounds of this stmctural type are restricted to the Fabaceae (Dewick, 1982,1988 Williams and Harbome, 1989b). Study of the biosynthesis of coumestans has been accomplished because elicitors stimulate synthesis of these compounds in plant cell cultures (Grisebach, 1985). The only known coumestan glycoside occurs in Eclipta alba (Asteraceae). 

Estrogenic Glycosides (Isoflavones, Coumestans) Coumarin Glycosides Goitrogenic Glycosides Other Glycosides... 

Almost half of the isoflavonoids identified from the Leguminosae, in which prenylated isoflavones constitute >50% of the total (pterocarpanoids, rotenoids, isoflavanones, isoflavans, coumestans, 3-arylcoumarins, and coumaronochromones), exhibit a high degree of structural diversity and complexity of prenylation.8,86"148 More than half of the isoflavones are monoprenylated, whereas 40% are diprenylated, and very few are triprenyl derivatives, with prenylation at positions 6>8>3 5 >6,>2 and O-methylation at 4 >7=6=2 =3 >5 =5>8. A number of novel isoflavonoid structures with rare skeletons, as well as complex isoflavone O- and C-glycosides have recently been reported.8,148... 

---