Elaboration of the 6,7,8 Oxygenation Pattern in Simple Coumarins: Biosynthesis of Puberulin in Agathosma puberula Fourc.1
نویسنده
چکیده
Biosynthesis, Puberulin, C oum arins, Agathosma puberula Umbelliferone and scopoletin are well utilized as precursors o f puberulin , a 7-O-prenyl e ther o f isofraxidin elaborated by Agathosma puberula Fourc. (R utaceae). As ferulic, sinapic, and caffeic acids were all m ore poorly utilized than 4 '-hydroxycinnam ic (/?-coumaric) acid, the partial biosynthetic route: 4 '-hydroxycinnam ic acid -*-> um belliferone -*• aesculetin -* scopo letin -*-► puberulin is suggested as the m ajor pathw ay. Prenyl e ther form ation apparen tly occurs at or beyond the scopoletin stage. The im plication that feru lic acid does not partic ipa te in the formation of scopoletin from 4 '-hydroxycinnam ic acid is a t variance with the known role o f ferulic acid as a scopoletin precursor in tobacco.
منابع مشابه
Unusual Coumarin Patterns of Pelargonium Species Forming the Origin of the Traditional Herbal Medicine Umckaloabo
Z. Naturforsch. 55c, 5 2 8 -5 3 3 (2000); received April 5/April 20. 2000 Pelargonium Species, Umckaloabo, Coumarins, Oxygenation Pattern The coumarin patterns of Pelargonium sidoides DC. and Pelargonium reniforme CURT., forming the origin of the herbal medicine “umckaloabo”, were analysed and compared for therapeutic equivalence. For both species, members of triand tetraoxygenated coumarins al...
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