Coumarins from Ferulago capillaris and F-brachyloba

Four new coumarins, (+)-senecioylprangol, (-)-3 '-senecioyloxymarmesin, (+)-3 '-hydroxyprantschimgin and (+)-2"-senecioyloxymarmesin, besides 12 known coumarins have been isolated from two Ferulago species. Their structures have been established by spectroscopic methods and partial synthesis. New synthetic 3'-oxocoumarins are also described. There is a remarkable difference in the contents of the most abundant coumarins found in the roots of both species: osthol and aurapten are specific to F. capillaris and F. brachyloba, respectively. (C) 2000 Elsevier Science Ltd. All rights reserved.